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Sample records for abarema cochliacarpos gomes

  1. Chronic administration of Abarema cochliacarpos attenuates colonic inflammation in rats

    Maria Silene da Silva

    2011-08-01

    Full Text Available Inflammatory bowel diseases are characterized by a chronic clinical course of relapse and remission associated with self-destructive inflammation of the gastrointestinal tract. Active extracts from plants have emerged as natural potential candidates for its treatment. Abarema cochliacarpos (Gomes Barneby & Grimes, Fabaceae (Barbatimão, is a native medicinal plant in to Brazil. Previously we have demonstrated in an acute colitis model a marked protective effect of a butanolic extract, so we decided to assess its anti-inflammatory effect in a chronic ulcerative colitis model induced by trinitrobenzensulfonic acid (TNBS. Abarema cochliacarpos (150 mg/day, v.o. was administered for fourteen consecutive days. This treatment decreased significantly macroscopic damage as compared with TNBS. Histological analysis showed that the extract improved the microscopic structure. Myeloperoxidase activity (MPO was significantly decreased. Study of cytokines showed that TNF-α was diminished and IL-10 level was increased after Abarema cochliacarpos treatment. In order to elucidate inflammatory mechanisms, expression of cyclooxygenase (COX-2 and nitric oxide synthase (iNOS were studied showing a significant downregulation. In addition, there was reduction in the JNK and p-38 activation. Finally, IκB degradation was blocked by Abarema cochliacarpos treatment being consistent with an up-regulation of the NF-kappaB-binding activity. These results reinforce the anti-inflammatory effects described previously suggesting that Abarema cochliacarpos could provide a source for the search for new anti-inflammatory compounds useful in ulcerative colitis treatment.

  2. GOME Ozonprofile: Weiterentwicklung und Validierung

    Bramstedt, Klaus

    2001-01-01

    Height-resolved ozone information on a global scale is required forthe detection of changes in the atmospheric ozone distribution and for researchinto the underlying chemical and dynamical processes. The Global OzoneMonitoring Experiment (GOME) makes an important contribution in thisfield. GOME aboard ESA´s ERS-2 satellite measures the reflected andbackscattered radiation from the Earth in the ultraviolet and visiblespectral range at moderate spectral resolution in nadir viewinggeometry. Vert...

  3. Tropical tropospheric ozone column retrieval for GOME-2

    P. Valks

    2014-01-01

    Full Text Available This paper presents the operational retrieval of tropical tropospheric ozone columns (TOC from the Second Global Ozone Monitoring Experiment (GOME-2 instruments using the convective-cloud-differential (CCD method. The retrieval is based on total ozone and cloud property data provided by the GOME Data Processor (GDP 4.7, and uses above-cloud and clear-sky ozone column measurements to derive a monthly mean TOC between 20° N and 20° S. Validation of the GOME-2 TOC with several tropical ozonesonde sites shows good agreement, with a high correlation between the GOME-2 and sonde measurements, and small biases within ~ 3 DU. The TOC data have been used in combination with tropospheric NO2 measurements from GOME-2 to analyse the effect of the 2009–2010 El Niño–Southern Oscillation (ENSO on the tropospheric ozone distribution in the tropics. El-Niño induced dry conditions in September–October 2009 resulted in relatively high tropospheric ozone columns over the southern Indian Ocean and northern Australia, while La Niña conditions in September–October 2010 resulted in a strong increase in tropospheric NO2 in South America, and enhanced ozone in the eastern Pacific and South America. Comparisons of the GOME-2 tropospheric ozone data with simulations of the ECHAM/MESSy Atmospheric Chemistry (EMAC model for 2009 El Nino conditions, illustrate the usefulness of the GOME-2 TOC measurements in evaluating chemistry climate models. Evaluation of CCMs with appropriate satellite observations helps to identify strengths and weaknesses of the model systems, providing a better understanding of driving mechanisms and adequate relations and feedbacks in the Earth atmosphere, and finally leading to improved models.

  4. An improved NO2 retrieval for the GOME-2 satellite instrument

    Richter, A; M. Begoin; Hilboll, A.; Burrows, J. P.

    2011-01-01

    Satellite observations of nitrogen dioxide (NO2) provide valuable information on both stratospheric and tropospheric composition. Nadir measurements from GOME, SCIAMACHY, OMI, and GOME-2 have been used in many studies on tropospheric NO2 burdens, the importance of different NOx emissions sources and their change over time. The observations made by the three GOME-2 instruments will extend the existing data set by more than a decade, and a high quality of the data as well as t...

  5. Monitoring of volcanic sulfur dioxide emissions and estimation of the plume height using GOME-2 measurements

    Rix, Meike

    2015-01-01

    This thesis addresses the monitoring of volcanic SO2 emissions using the GOME-2 satellite instrument and the development of a near-real time plume height estimation. The SO2 total columns are retrieved from GOME-2 measurements using the differential optical absorption spectroscopy (DOAS). The standard DOAS technique assumes optically thin atmospheric conditions, which leads to underestimation of high total SO2 columns. By applying the DOAS method to synthetic GOME-2 spectra the strengths...

  6. Overview of the O3M SAF GOME-2 operational atmospheric composition and UV radiation data products and data availability

    Hassinen, S.; D. Balis; H. Bauer; Begoin, M.; A. Delcloo; Eleftheratos, K.; S. Gimeno Garcia; Granville, J.; Grossi, M; Hao, N.; Hedelt, P.; Hendrick, F; Hess, M.; K.-P. Heue; J. Hovila

    2015-01-01

    The three GOME-2 instruments will provide unique and long data sets for atmospheric research and applications. The complete time period will be 2007–2022, including the period of ozone depletion as well as the beginning of ozone layer recovery. Besides ozone chemistry, the GOME-2 products are important e.g. for air quality studies, climate modeling, policy monitoring and hazard warnings. The heritage for GOME-2 is in the ERS/GOME and Envis...

  7. Comparison of GOME total ozone data with ground data from the Spanish Brewer spectroradiometers

    M. Antón

    2008-03-01

    Full Text Available This paper compares total ozone measurements from five Brewer spectroradiometers located at the Iberian Peninsula with satellite observations given by the GOME (Global Ozone Monitoring Experiment sensor. The analyzed period covers simultaneous ozone values from July 1995 until December 2004. The regression analysis shows an excellent agreement between Brewer-GOME values in the five locations; the coefficient of correlation is always higher than 0.92 and the root mean square error is about 3%. Moreover, the comparison shows that the satellite retrieval accuracy is within the uncertainty of current ground-based instruments. In addition, the effects of several variables, such as cloudiness, solar zenith angle (SZA, effective temperature and total ozone values in Brewer-GOME differences are analyzed. The results indicate that clouds induce a minor dependence of GOME values on the SZA. For example, during heavy cloudy conditions in Madrid station, GOME observations overestimate ground-based Brewer data for low AMF (low SZA values by 2% while for high AMF (high SZA values the satellite underestimates ground-based ozone values by 1%. Moreover, the dependence of Brewer-GOME differences with respect to SZA for cloud-free conditions may be due to the variability of effective temperature. This fact could indicate that the effective temperature estimated by GOME does not fully reflect the actual atmospheric temperature variability. Finally, GOME ozone observations slightly underestimate the highest values measured by the Brewer spectrophotometers and overestimates the lowest ground-based measurements.

  8. Development of a prototype algorithm for the operational retrieval of height-resolved products from GOME

    Spurr, Robert J. D.

    1997-01-01

    Global ozone monitoring experiment (GOME) level 2 products of total ozone column amounts have been generated on a routine operational basis since July 1996. These products and the level 1 radiance products are the major outputs from the ERS-2 ground segment GOME data processor (GDP) at DLR in Germany. Off-line scientific work has already shown the feasibility of ozone profile retrieval from GOME. It is demonstrated how the retrievals can be performed in an operational context. Height-resolved retrieval is based on the optimal estimation technique, #and cloud-contaminated scenes are treated in an equivalent reflecting surface approximation. The prototype must be able to handle GOME measurements routinely on a global basis. Requirements for the major components of the algorithm are described: this incorporates an overall strategy for operational height-resolved retrieval from GOME.

  9. Memórias Póstumas de Dias Gomes

    Igor Sacramento

    2009-10-01

    Full Text Available  Este artigo analisa os discursos midiáticos acerca da morte de Dias Gomes em quatro periódicos cariocas (Extra, Jornal do Brasil, O Dia e O Globo. Tal caso, além de ser uma oportunidade para estudar os diferentes “modos de dizer” das mídias no trabalho de construção desse acontecimento e da história de vida daquele intelectual, é uma chance para reavaliar a prática biográfica na sociedade midiatizada.

  10. Retrieval and Analysis of Stratospheric NO2 from GOME

    Wenig, M.; Kuehl, S.; Beirle, S.; Wagner, T.; Jaehne, B.; Platt, U.

    2003-01-01

    In this paper we describe the retrieval of stratospheric NO2 from the GOME (Global Ozone Monitoring Experiment) spectrometer. For this retrieval the Differential Optical Absorption Spectroscopy (DOAS) is used and we describe the influence of the instrument s characteristics on this measurement technique. This analysis led to an improved version of the DOAS algorithm resulting in results with lower systematic errors. Subsequently these results were used to separate the tropospheric and stratospheric fraction of the measured NO;! in the atmosphere. This paper is focusing on the annual variations of the stratospheric distribution of nitrogen oxides. For this examination the satellite data from beginning of 1996 to the end of 2001 was used and has been visualized in a plot zonal means versus time of the year, a visualization which proved to be very useful for Ozone. Additionally the so called "Noxon Cliff", a drop of NO2 column densities Noxon measured in 1975-77 while traveling northwards towards the pole in Canada, is shown. Also its southern equivalent could be discovered in the GOME data.

  11. Comparison of GOME-2/Metop total column water vapour with ground-based and in situ measurements

    N. Kalakoski

    2014-12-01

    Full Text Available Total column water vapour product from the Global Ozone Monitoring Experiment-2 on board Metop-A and Metop-B satellites (GOME-2/Metop-A and GOME-2/Metop-B produced by the Satellite Application Facility on Ozone and Atmospheric Chemistry Monitoring (O3M SAF is compared with co-located radiosonde and Global Positioning System (GPS observations. The comparisons are performed using recently reprocessed data by the GOME Data Processor (GDP version 4.7. The comparisons are performed for the period of January 2007–July 2013 (GOME-2A and from December 2012 to July 2013 (GOME-2B. Radiosonde data are from the Integrated Global Radiosonde Archive (IGRA maintained by National Climatic Data Center (NCDC and screened for soundings with incomplete tropospheric column. Ground-based GPS observations from COSMIC/SuomiNet network are used as the second independent data source. Good general agreement between GOME-2 and the ground-based observations is found. The median relative difference of GOME-2 to radiosonde observations is −2.7% for GOME-2A and −0.3% for GOME-2B. Against GPS observations, the median relative differences are 4.9 and 3.2% for GOME-2A and B, respectively. For water vapour total columns below 10 kg m−2, large wet biases are observed, especially against GPS observations. Conversely, at values above 50 kg m−2, GOME-2 generally underestimates both ground-based observations.

  12. Validation of GOME-2/Metop total column water vapour with ground-based and in situ measurements

    Kalakoski, Niilo; Kujanpää, Jukka; Sofieva, Viktoria; Tamminen, Johanna; Grossi, Margherita; Valks, Pieter

    2016-04-01

    The total column water vapour product from the Global Ozone Monitoring Experiment-2 on board Metop-A and Metop-B satellites (GOME-2/Metop-A and GOME-2/Metop-B) produced by the Satellite Application Facility on Ozone and Atmospheric Chemistry Monitoring (O3M SAF) is compared with co-located radiosonde observations and global positioning system (GPS) retrievals. The validation is performed using recently reprocessed data by the GOME Data Processor (GDP) version 4.7. The time periods for the validation are January 2007-July 2013 (GOME-2A) and December 2012-July 2013 (GOME-2B). The radiosonde data are from the Integrated Global Radiosonde Archive (IGRA) maintained by the National Climatic Data Center (NCDC). The ground-based GPS observations from the COSMIC/SuomiNet network are used as the second independent data source. We find a good general agreement between the GOME-2 and the radiosonde/GPS data. The median relative difference of GOME-2 to the radiosonde observations is -2.7 % for GOME-2A and -0.3 % for GOME-2B. Against the GPS, the median relative differences are 4.9 % and 3.2 % for GOME-2A and B, respectively. For water vapour total columns below 10 kg m-2, large wet biases are observed, especially against the GPS retrievals. Conversely, at values above 50 kg m-2, GOME-2 generally underestimates both ground-based observations.

  13. Retrieval of global water vapour columns from GOME-2 and first applications in polar regions

    S. Noël

    2007-12-01

    Full Text Available Global total water vapour columns have been derived from measurements of the Global Ozone Monitoring Experiment 2 (GOME-2 on MetOp. For this purpose, the Air Mass Corrected Differential Optical Absorption Spectroscopy (AMC-DOAS method has been adapted, which has already been applied successfully to GOME (on ERS-2 and SCIAMACHY (SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY, on ENVISAT data. Comparisons between the derived GOME-2 and SCIAMACHY water vapour columns show a good overall agreement. This gives confidence that the time series of water vapour columns from GOME-type instruments which started in 1995 can be continued by the MetOp instrumentation until at least 2020. The enhanced temporal and spatial resolution of GOME-2 enables the analysis of short-term variations particularly in the polar regions. This is especially important since atmospheric data sources in the polar regions are generally sparse. As an exemplary application, daily water vapour concentrations over the polar research station Ny Ålesund (78°55'19" N/11°56'33" E are investigated. At this latitude GOME-2 gives about six data points during daylight hours at varying local times. The results of this study show that it is possible to derive information about the diurnal variability of water vapour in polar regions from GOME-2 measurements.

  14. The GOME-2 total column ozone product: Retrieval algorithm and ground-based validation

    Loyola, D. G.; Koukouli, M. E.; Valks, P.; Balis, D. S.; Hao, N.; van Roozendael, M.; Spurr, R. J. D.; Zimmer, W.; Kiemle, S.; Lerot, C.; Lambert, J.-C.

    2011-04-01

    The Global Ozone Monitoring Instrument (GOME-2) was launched on EUMESAT's MetOp-A satellite in October 2006. This paper is concerned with the retrieval algorithm GOME Data Processor (GDP) version 4.4 used by the EUMETSAT Satellite Application Facility on Ozone and Atmospheric Chemistry Monitoring (O3M-SAF) for the operational generation of GOME-2 total ozone products. GDP 4.4 is the latest version of the GDP 4.0 algorithm, which is employed for the generation of official Level 2 total ozone and other trace gas products from GOME and SCIAMACHY. Here we focus on enhancements introduced in GDP 4.4: improved cloud retrieval algorithms including detection of Sun glint effects, a correction for intracloud ozone, better treatment of snow and ice conditions, accurate radiative transfer modeling for large viewing angles, and elimination of scan angle dependencies inherited from Level 1 radiances. Furthermore, the first global validation results for 3 years (2007-2009) of GOME-2/MetOp-A total ozone measurements using Brewer and Dobson measurements as references are presented. The GOME-2/MetOp-A total ozone data obtained with GDP 4.4 slightly underestimates ground-based ozone by about 0.5% to 1% over the middle latitudes of the Northern Hemisphere and slightly overestimates by around 0.5% over the middle latitudes in the Southern Hemisphere. Over high latitudes in the Northern Hemisphere, GOME-2 total ozone has almost no offset relative to Dobson readings, while over high latitudes in the Southern Hemisphere GOME-2 exhibits a small negative bias below 1%. For tropical latitudes, GOME-2 measures on average lower ozone by 0% to 2% compared to Dobson measurements.

  15. Operational total and tropospheric NO2 column retrieval for GOME-2

    M. Van Roozendael

    2011-03-01

    Full Text Available This paper presents the algorithm for the operational near real time retrieval of total and tropospheric NO2 columns from the Global Ozone Monitoring Experiment (GOME-2. The retrieval is performed with the GOME Data Processor (GDP version 4.4 as used by the EUMETSAT Satellite Application Facility on Ozone and Atmospheric Chemistry Monitoring (O3M-SAF. The Differential Optical Absorption Spectroscopy (DOAS method is used to determine NO2 slant columns from GOME-2 (irradiance data in the 425–450 nm range. Initial total NO2 columns are computed using stratospheric air mass factors, and GOME-2 derived cloud properties are used to calculate the air mass factors for scenarios in the presence of clouds. To obtain the stratospheric NO2 component, a spatial filtering approach is used, which is shown to be an improvement on the Pacific reference sector method. Tropospheric air mass factors are computed using monthly averaged NO2 profiles from the MOZART-2 chemistry transport model. An error assessment shows that the random error in the GOME-2 NO2 slant columns is approximately 0.45 × 1015 molec cm−2. As a result of the improved quartz diffuser plate used in the GOME-2 instrument, the systematic error in the slant columns is strongly reduced compared to GOME/ERS-2. The estimated uncertainty in the GOME-2 tropospheric NO2 column for polluted conditions ranges from 40 to 80%. An end-to-end ground-based validation approach for the GOME-2 NO2 columns is illustrated based on MAX-DOAS measurements at the Observatoire de Haute Provence (OHP. The GOME-2 stratospheric NO2 columns are found to be in good overall agreement with coincident ground-based measurements at OHP. A time series of the MAX-DOAS and the GOME-2 tropospheric NO2 columns shows that pollution episodes at OHP are well captured by GOME-2. Monthly mean tropospheric columns are in very good agreement, with differences generally within 0.5 × 1015 molec cm−2.

  16. Manuel Gomes de Lima Bezerra : o discurso ilustrado pela dignificação da cirurgia

    Tavares, Pedro Vilas Boas

    2014-01-01

    The article offers a brief recollection of Manuel Gomes de Lima Bezerra’s actions pursuing the regeneration of medicine and surgery in Portugal in the 18th century, emphasizing one of the most important vectors of his enlightened «civic campaign»: the need for surgeons to be recognized by the State and to be –the more distinguished among them – generously paid. Key words: Manuel Gomes de Lima Bezerra? surgery in Portugal, 18th century.

  17. Intercomparison of cloud top altitudes as derived using GOME and ATSR-2 instruments onboard ERS-2

    Rozanov, V. V.; A. A. Kokhanovsky; Loyola, Diego; Siddans, R.; Latter, B.; Stevens, A.; J. P. Burrows

    2006-01-01

    Cloud top heights as derived using measurements of two instruments (GOME and ATSR-2) onboard the ESA ERS-2 space platform are intercompared. It was found that cloud altitudes obtained using thermal IR measurements of ATSR-2 highly correlate with those obtained from top-of-atmosphere backscattered solar light measurements of GOME in O2 A-band using both the semi-analytical cloud retrieval algorithm SACURA and the neural network cloud retrieval algorithm ROCINN. The average cloud top heights as...

  18. An improved NO2 retrieval for the GOME-2 satellite instrument

    Richter, A.; Begoin, M.; Hilboll, A.; Burrows, J. P.

    2011-06-01

    Satellite observations of nitrogen dioxide (NO2) provide valuable information on both stratospheric and tropospheric composition. Nadir measurements from GOME, SCIAMACHY, OMI, and GOME-2 have been used in many studies on tropospheric NO2 burdens, the importance of different NOx emissions sources and their change over time. The observations made by the three GOME-2 instruments will extend the existing data set by more than a decade, and a high quality of the data as well as their good consistency with existing time series is of particular importance. In this paper, an improved GOME-2 NO2 retrieval is described which reduces the scatter of the individual NO2 columns globally but in particular in the region of the Southern Atlantic Anomaly. This is achieved by using a larger fitting window including more spectral points, and by applying a two step spike removal algorithm in the fit. The new GOME-2 data set is shown to have good consistency with SCIAMACHY NO2 columns. Remaining small differences are shown to be linked to changes in the daily solar irradiance measurements used in both GOME-2 and SCIAMACHY retrievals. In the large retrieval window, a not previously identified spectral signature was found which is linked to deserts and other regions with bare soil. Inclusion of this empirically derived pseudo cross-section significantly improves the retrievals and potentially provides information on surface properties and desert aerosols. Using the new GOME-2 NO2 data set, a long-term average of tropospheric columns was computed and high-pass filtered. The resulting map shows evidence for pollution from several additional shipping lanes, not previously identified in satellite observations. This illustrates the excellent signal to noise ratio achievable with the improved GOME-2 retrievals.

  19. Comparison of GOME total ozone data with ground data from the Spanish Brewer spectroradiometers

    Antón, M.; Loyola, D.; Navascúes, B.; P. Valks

    2008-01-01

    This paper compares total ozone measurements from five Brewer spectroradiometers located at the Iberian Peninsula with satellite observations given by the GOME (Global Ozone Monitoring Experiment) sensor. The analyzed period covers simultaneous ozone values from July 1995 until December 2004. The regression analysis shows an excellent agreement between Brewer-GOME values in the five locations; the coefficient of correlation is always higher than 0.92 and the root mean square error is about 3%...

  20. Highly resolved global distribution of tropospheric NO2 using GOME narrow swath mode data

    S. Beirle

    2004-01-01

    Full Text Available The Global Ozone Monitoring Experiment (GOME allows the retrieval of tropospheric vertical column densities (VCDs of NO2 on a global scale. Regions with enhanced industrial activity can clearly be detected, but the standard spatial resolution of the GOME ground pixels (320x40km2 is insufficient to resolve regional trace gas distributions or individual cities. Every 10 days within the nominal GOME operation, measurements are executed in the so called narrow swath mode with a much better spatial resolution (80x40km2. We use this data (1997-2001 to construct a detailed picture of the mean global tropospheric NO2 distribution. Since - due to the narrow swath - the global coverage of the high resolution observations is rather poor, it has proved to be essential to deseasonalize the single narrow swath mode observations to retrieve adequate mean maps. This is done by using the GOME backscan information. The retrieved high resolution map illustrates the shortcomings of the standard size GOME pixels and reveals an unprecedented wealth of details in the global distribution of tropospheric NO2. Localised spots of enhanced NO2 VCD can be directly associated to cities, heavy industry centers and even large power plants. Thus our result helps to check emission inventories. The small spatial extent of NO2 'hot spots' allows us to estimate an upper limit of the mean lifetime of boundary layer NOx of 17h on a global scale. The long time series of GOME data allows a quantitative comparison of the narrow swath mode data to the nominal resolution. Thus we can analyse the dependency of NO2 VCDs on pixel size. This is important for comparing GOME data to results of new satellite instruments like SCIAMACHY (launched March 2002 on ENVISAT, OMI (launched July 2004 on AURA or GOME II (to be launched 2005 with an improved spatial resolution.

  1. An improved NO2 retrieval for the GOME-2 satellite instrument

    J. P. Burrows

    2011-01-01

    Full Text Available Satellite observations of nitrogen dioxide (NO2 provide valuable information on both stratospheric and tropospheric composition. Nadir measurements from GOME, SCIAMACHY, OMI, and GOME-2 have been used in many studies on tropospheric NO2 burdens, the importance of different NOx emissions sources and their change over time. The observations made by the three GOME-2 instruments will extend the existing data set by more than a decade, and a high quality of the data as well as their good consistency with existing time series is of high importance. In this paper, an improved GOME-2 NO2 retrieval is described which reduces the scatter of the individual NO2 columns globally but in particular in the region of the Southern Atlantic Anomaly. This is achieved by using a larger fitting window including more spectral points, and by applying a two step spike removal algorithm in the fit. The new GOME-2 data set is shown to have good consistency with SCIAMACHY NO2 columns. Remaining small differences are shown to be linked to changes in the daily solar irradiance measurements used in both GOME-2 and SCIAMACHY retrievals. In the large retrieval window, a not previously identified spectral signature was found which is linked to deserts and other regions with bare soil. Inclusion of this empirically derived pseudo cross-section significantly improves the retrievals and potentially provides information on surface properties and desert aerosols. Using the new GOME-2 NO2 data set, a long-term average of tropospheric columns was computed and high-pass filtered. The resulting map shows evidence for pollution from several additional shipping lanes, not previously identified in satellite observations. This illustrates the excellent signal to noise ratio achievable with the improved GOME-2 retrievals.

  2. Geophysical validation and long-term consistency between GOME-2/MetOp-A total ozone column and measurements from the sensors GOME/ERS-2, SCIAMACHY/ENVISAT and OMI/Aura

    M. E. Koukouli

    2012-09-01

    Full Text Available The main aim of the paper is to assess the consistency of five years of Global Ozone Monitoring Experiment-2/Metop-A [GOME-2] total ozone columns and the long-term total ozone satellite monitoring database already in existence through an extensive inter-comparison and validation exercise using as reference Brewer and Dobson ground-based measurements. The behaviour of the GOME-2 measurements is being weighed against that of GOME (1995–2011, Ozone Monitoring Experiment [OMI] (since 2004 and the Scanning Imaging Absorption spectroMeter for Atmospheric CartograpHY [SCIAMACHY] (since 2002 total ozone column products. Over the background truth of the ground-based measurements, the total ozone columns are inter-evaluated using a suite of established validation techniques; the GOME-2 time series follow the same patterns as those observed by the other satellite sensors. In particular, on average, GOME-2 data underestimate GOME data by about 0.80%, and underestimate SCIAMACHY data by 0.37% with no seasonal dependence of the differences between GOME-2, GOME and SCIAMACHY. The latter is expected since the three datasets are based on similar DOAS algorithms. This underestimation of GOME-2 is within the uncertainty of the reference data used in the comparisons. Compared to the OMI sensor, on average GOME-2 data underestimate OMI_DOAS (collection 3 data by 1.28%, without any significant seasonal dependence of the differences between them. The lack of seasonality might be expected since both the GOME data processor [GDP] 4.4 and OMI_DOAS are DOAS-type algorithms and both consider the variability of the stratospheric temperatures in their retrievals. Compared to the OMI_TOMS (collection 3 data, no bias was found. We hence conclude that the GOME-2 total ozone columns are well suitable to continue the long-term global total ozone record with the accuracy needed for climate monitoring studies.

  3. GOME-2 total ozone columns from MetOp-A/MetOp-B and assimilation in the MACC system

    N. Hao

    2014-03-01

    Full Text Available The two Global Ozone Monitoring Instrument (GOME-2 sensors operated in tandem are flying onboard EUMETSAT's MetOp-A and MetOp-B satellites, launched in October 2006 and September 2012 respectively. This paper presents the operational GOME-2/MetOp-A (GOME-2A and GOME-2/MetOp-B (GOME-2B total ozone products provided by the EUMETSAT Satellite Application Facility on Ozone and Atmospheric Chemistry Monitoring (O3M-SAF. These products are generated using the latest version of the GOME Data Processor (GDP version 4.7. The enhancements in GDP 4.7, including the application of Brion–Daumont–Malicet ozone absorption cross-sections, are presented here. On a global scale, GOME-2B has the same high accuracy as the corresponding GOME-2A products. There is an excellent agreement between the ozone total columns from the two sensors, with GOME-2B values slightly lower with a mean difference of only 0.55 ± 0.29%. First global validation results for 6 months of GOME-2B total ozone using ground-based measurements show that on average the GOME-2B total ozone data obtained with GDP 4.7 slightly overestimate Dobson observations by about 2.0 ± 1.0% and Brewer observations by about 1.0 ± 0.8%. It is concluded that the total ozone columns (TOCs provided by GOME-2A and GOME-2B are consistent and may be used simultaneously without introducing trends or other systematic effects. GOME-2A total ozone data have been used operationally in the Copernicus atmospheric service project MACC-II (Monitoring Atmospheric Composition and Climate – Interim Implementation near-real-time (NRT system since October 2013. The magnitude of the bias correction needed for assimilating GOME-2A ozone is reduced (to about −6 DU in the global mean when the GOME-2 ozone retrieval algorithm changed to GDP 4.7.

  4. Geophysical validation and long-term consistency between GOME-2/MetOp-A total ozone column and measurements from the sensors GOME/ERS-2, SCIAMACHY/ENVISAT and OMI/Aura

    M. E. Koukouli

    2012-04-01

    Full Text Available The main aim of the paper is to assess the consistency of five years of Global Ozone Monitoring Experiment-2/Metop-A (GOME-2 total ozone columns and the long-term total ozone satellite monitoring database already in existence through an extensive inter-comparison and validation exercise using as reference Brewer and Dobson ground-based measurements. The behaviour of the GOME-2 measurements is being weighed against that of GOME (1995–2011, Ozone Monitoring Experiment (OMI (since 2004 and the Scanning Imaging Absorption spectroMeter for Atmospheric CartograpHY (SCIAMACHY (since 2002 total ozone column products. Over the background truth of the ground-based measurements, the total ozone columns are inter-evaluated using a suite of established validation techniques; the GOME-2 time series follow the same patterns as those observed by the other satellite sensors and in particular, on the average, GOME-2 data underestimate GOME data by about 0.80%, and underestimate SCIAMACHY data by 0.37% with no seasonal dependence of the differences between GOME-2, GOME and SCIAMACHY. The latter is expected since the three data sets are based on similar DOAS algorithms. This underestimation of GOME-2 is within the uncertainty of the reference data used in the comparisons. Compared to the OMI sensor, on the average GOME-2 data underestimate OMI_DOAS (collection 3 data by 1.28%, without any significant seasonal dependence of the differences between them. The lack of seasonality might be expected since both GDP 4.4 and OMI_DOAS are DOAS-type algorithms and both consider the variability of the stratospheric temperatures in their retrievals. Compared to the OMI_TOMS (collection 3 data, no bias was found. We hence conclude that the GOME-2 total ozone columns are well suitable to continue the long-term global total ozone record with the accuracy needed for climate monitoring studies.

  5. Global ozone forecasting based on ERS-2 GOME observations

    H. J. Eskes

    2002-07-01

    Full Text Available The availability of near-real time ozone observations from satellite instruments has recently initiated the development of ozone data assimilation systems. In this paper we present the results of an ozone assimilation and forecasting system, in use since Autumn 2000. The forecasts are produced by an ozone transport and chemistry model, driven by the operational medium range forecasts of ECMWF. The forecasts are initialised with realistic ozone distributions, obtained by the assimilation of near-real time total column observations of the GOME spectrometer on ERS-2. The forecast error diagnostics demonstrate that the system produces meaningful total ozone forecasts for up to 6 days in the extratropics. In the tropics meaningful forecasts of the small anomalies are restricted to shorter periods of about two days with the present model setup. It is demonstrated that important events, such as the breakup of the South Pole ozone hole and mini-hole events above Europe can be successfully predicted 4--5 days in advance.

  6. Detection of polar stratospheric clouds with ERS2/GOME data

    Based on radiative transfer calculations it is studied whether Polar Stratospheric Clouds (PSCs) can be detected by the new Global Ozone Monitoring Experiment (GOME) onboard the second European Research Satellite (ERS-2) planned to be launched in winter 1994/95. It is proposed to identify PSC covered areas by use of an indicator, the Normalized Radiance Difference (NRD), which relates the difference of two spectral radiances at 0.5 μm and 0.7 μm to one radiance measured in the center of the oxygen A-band at 0.76 μm. The presence of PSCs and under conditions of large solar zenith angles Θ>80 the NRD values are clearly below those derived under conditions of a cloud free stratosphere. In this case the method is successful for PSCs with optical depths greater than 0.03 at 0.55 μm. It is not affected by existing tropospheric clouds and by different tropospheric aerosol loadings or surface albedoes. For solar zenith angles Θ<80 PSCs located above a cloud free troposphere are detectable. PSC detection becomes difficult for Θ<80 when highly reflecting tropospheric clouds like dense cirrus or stratus clouds affect spectral radiances measured at the top of the atmosphere. (orig.)

  7. Global satellite validation of SCIAMACHY O3 columns with GOME WFDOAS

    A. Bracher

    2005-01-01

    Full Text Available Global stratospheric ozone columns derived from UV nadir spectra measured by SCIAMACHY (Scanning Imaging Spectrometer for Atmospheric Chartography; data ESA Versions 5.01 and 5.04 aboard the recently launched Environmental Satellite (ENVISAT from January to June 2003 were compared to collocated total ozone data from GOME (Global Ozone Monitoring Experiment on ERS-2 retrieved using the weighting function DOAS algorithm (WFDOAS; Version 1.0 in order to assess the level-2 data (trace gas data retrieval accuracy from SCIAMACHY. In addition, SCIAMACHY ozone columns retrieved with WFDOAS V1.0 were compared to GOME WFDOAS for some selected days in 2003 in order to separate data quality issues that either come from the optical performance of the instrument or algorithm implementation. Large numbers of collocated total ozone data from the two instruments, which are flying in the same orbit about 30 min apart, were spatially binned into regular 2.5° times 2.5° grids and then compared. Results of these satellite comparisons show that SCIAMACHY O3 vertical columns (ESA Version 5.01/5.04 are on average 1% (±2% lower than GOME WFDOAS and scatter increases at solar zenith angles above 85° and at very low total ozone values. Results show dependencies on the solar zenith angle, latitudes, and total ozone amounts which are explained by the implementation of an outdated GOME algorithm based on GOME Data Processor (GDP version 2.4 algorithms for the SCIAMACHY operational product. The reprocessing with an algorithm equivalent to GOME WFDOAS V1.0 shows that the offset and dependencies on solar zenith angle, latitude, and total ozone disappear and that SCIAMACHY WFDOAS data are within 1% of GOME WFDOAS. Since GOME lost its global coverage in July 2003 due to data rate limitation, continuation of the total ozone time series with SCIAMACHY is of highest importance for long-term trend monitoring. Since the beginning of its operation in March 2002 the SCIAMACHY

  8. Improvement of total and tropospheric NO2 column retrieval for GOME-2

    Liu, Song; Valks, Pieter; Pinardi, Gaia; De Smedt, Isabelle; Huan, Yu; Beirle, Steffen

    2016-04-01

    This contribution focuses on the development and refinement of novel scientific algorithms for the retrieval of total and tropospheric nitrogen dioxide (NO2) columns for the GOME-2 satellite instrument. NO2 plays significant roles in atmospheric chemistry. It is strongly related to ozone destruction in the stratosphere, and is regarded as an important air pollutant and ozone precursor in the troposphere. Total NO2 columns from GOME-2 are retrieved with the Differential Optical Absorption Spectroscopy (DOAS) method using the large 425-497 nm wavelength fitting window in order to increase the signal to noise ratio. The tropospheric NO2 column is derived using an improved Stratospheric-Tropospheric separation (STS) algorithm, followed by an air mass factor (AMF) conversion calculated with the LIDORT model. For the calculation of the tropospheric AMF, improved GOME-2 cloud parameters are used and a new surface albedo (LER) climatology based on GOME-2 observations for 2007-2013 is applied. We present the improvements in the NO2 retrieval algorithm, and we show examples of air quality applications with GOME-2 NO2 data.

  9. Estimates of lightning NOx production from GOME satellite observations

    H. M. Kelder

    2005-05-01

    Full Text Available Tropospheric NO2 column retrievals from the Global Ozone Monitoring Experiment (GOME satellite spectrometer are used to quantify the source strength and 3D distribution of lightning produced nitrogen oxides (NOx=NO2+NO2. A sharp increase of NO2 is observed at convective cloud tops with increasing cloud top height, consistent with a power-law behaviour with power 5±2. Convective production of clouds with the same cloud height are found to produce NO2 with a ratio 1.6/1 for continents compared to oceans. This relation between cloud properties and NO2 is used to construct a 10:30 local time global lightning NO2 production map for 1997. An extensive statistical comparison is conducted to investigate the capability of the TM3 chemistry transport model to reproduce observed patterns of lightning NO2 in time and space. This comparison uses the averaging kernel to relate modelled profiles of NO2 to observed NO2 columns. It exploits a masking scheme to minimise the interference of other NOx sources on the observed total columns. Simulations are performed with two lightning parametrisations, one relating convective preciptation (CP scheme to lightning flash distributions, and the other relating the fifth power of the cloud top height (H5 scheme to lightning distributions. The satellite-retrieved NO2 fields show significant correlations with the simulated lightning contribution to the NO2 concentrations for both parametrisations. Over tropical continents modelled lightning NO2 shows remarkable quantitative agreement with observations. Over the oceans however, the two model lightning parametrisations overestimate the retrieved NO2 attributed to lightning. Possible explanations for these overestimations are discussed. The ratio between satellite-retrieved NO2 and modelled lightning NO2 is used to rescale the original modelled lightning NOx production. Eight estimates of the lightning NOx production in 1997 are obtained from spatial and temporal correlation

  10. Estimates of lightning NOx production from GOME satellite observations

    K. F. Boersma

    2005-01-01

    Full Text Available Tropospheric NO2 column retrievals from the Global Ozone Monitoring Experiment (GOME satellite spectrometer are used to quantify the source strength and 3-D distribution of lightning produced nitrogen oxides (NOx=NO+NO2. A sharp increase of NO2 is observed at convective cloud tops with increasing cloud top height, consistent with a power-law behaviour with power 5±2. Convective production of clouds with the same cloud height are found to produce NO2 with a ratio 1.6/1 for continents compared to oceans. This relation between cloud properties and NO2 is used to construct a 10:30 local time global lightning NO2 production map for 1997. An extensive statistical comparison is conducted to investigate the capability of the TM3 chemistry transport model to reproduce observed patterns of lightning NO2 in time and space. This comparison uses the averaging kernel to relate modelled profiles of NO2 to observed NO2 columns. It exploits a masking scheme to minimise the interference of other NOx sources on the observed total columns. Simulations are performed with two lightning parameterizations, one relating convective preciptation (CP scheme to lightning flash distributions, and the other relating the fifth power of the cloud top height (H5 scheme to lightning distributions. The satellite-retrieved NO2 fields show significant correlations with the simulated lightning contribution to the NO2 concentrations for both parameterizations. Over tropical continents modelled lightning NO2 shows remarkable quantitative agreement with observations. Over the oceans however, the two model lightning parameterizations overestimate the retrieved NO2 attributed to lightning. Possible explanations for these overestimations are discussed. The ratio between satellite-retrieved NO2 and modelled lightning NO2 is used to rescale the original modelled lightning NOx production. Eight estimates of the lightning NOx production in 1997 are obtained from spatial and temporal

  11. Comparison of GOME-2/Metop-A ozone profiles with GOMOS, OSIRIS and MLS measurements

    Määttä, A.; Tuinder, O. N. E.; Tukiainen, S.; Sofieva, V.; Tamminen, J.

    2015-07-01

    This paper presents a comparison of vertical ozone profiles retrieved by the Ozone ProfilE Retrieval Algorithm (OPERA) from the Global Ozone Monitoring Experiment 2 (GOME-2) measurements on board Metop-A with high-vertical-resolution ozone profiles by Global Ozone Monitoring by Occultation of Stars (GOMOS), Optical Spectrograph and Infrared Imager System (OSIRIS) and Microwave Limb Sounder (MLS). The comparison, with global coverage, focuses on the stratosphere and the lower mesosphere and covers the period from March 2008 until the end of 2011. The comparison shows an agreement of the GOME-2 ozone profiles with those of GOMOS, OSIRIS and MLS within ±15 % in the altitude range from 15 km up to ~ 35-40 km depending on latitude. The GOME-2 ozone profiles from non-degradation corrected radiances have a tendency to a systematic negative bias with respect to the reference data above ~ 30 km. The GOME-2 bias with respect to the high-vertical resolution instruments depends on season, with the strongest dependence observed at high latitudes.

  12. Evaluation of tropospheric ozone columns derived from assimilated GOME ozone profile observations

    A. T. J. de Laat

    2009-10-01

    Full Text Available Tropospheric O3 column estimates are produced and evaluated from spaceborne O3 observations by the subtraction of assimilated O3 profile observations from total column observations, the so-called Tropospheric O3 ReAnalysis or TORA method. Here we apply the TORA method to six years (1996–2001 of ERS-2 GOME/TOMS total O3 and ERS-2 GOME O3 profile observations using the TM5 global chemistry-transport model with a linearized O3 photochemistry parameterization scheme.

    Free running TM5 simulations show good agreement with O3 sonde observations in the upper-tropospheric and lower stratospheric region (UTLS, both for short day-to-day variability as well as for monthly means. The assimilation of GOME O3 profile observations counteracts the mid-latitude stratospheric O3 drift caused by the overstrong stratospheric meridional circulation in TM5. Assimilation of GOME O3 profile observations also improves the bias and correlations in the tropical UTLS region but slightly degrades the model-to-sonde correlations and bias of extra-tropical UTLS. We suggest that this degradation is related to the large ground pixel size of the GOME O3 measurements (960×100 km in combination with retrieval and calibration errors. The added value of the assimilation of GOME O3 profiles compared to stand-alone model simulations lays in the long term variations of stratospheric O3, not in short term synoptic variations.

    The evaluation of daily and monthly tropospheric O3 columns obtained from total column observations and using the TORA methodology shows that the use of GOME UV-VIS nadir O3 profiles in combination with the spatial resolution of the model does not result in satisfactory residual tropospheric ozone columns.

  13. Studies on calibration and validation of data provided by the Global Ozone Monitoring Experiment GOME on ERS-2 (CAVEAT). Final report; Studie zur Kalibrierung und Validation von Daten des Global Ozone Monitoring Experiments GOME auf ERS-2 (CAVEAT). Endbericht

    Burrows, J.P.; Kuenzi, K.; Ladstaetter-Weissenmayer, A.; Langer, J. [Bremen Univ. (Germany). Inst. fuer Umweltphysik; Neuber, R.; Eisinger, M. [Alfred-Wegener-Institut fuer Polar- und Meeresforschung, Potsdam (Germany)

    2000-04-01

    The Global Ozone Monitoring Experiment (GOME) was launched on 21 April 1995 as one of six scientific instruments on board the second European remote sensing satellite (ERS-2) of the ESA. The investigations presented here aimed at assessing and improving the accuracy of the GOME measurements of sun-standardized and absolute radiation density and the derived data products. For this purpose, the GOME data were compared with measurements pf terrestrial, airborne and satellite-borne systems. For scientific reasons, the measurements will focus on the medium and high latitudes of both hemispheres, although equatorial regions were investigated as well. In the first stage, operational data products of GOME were validated, i.e. radiation measurements (spectra, level1 product) and trace gas column densities (level2 product). [German] Am 21. April 1995 wurde das Global Ozone Monitoring Experiment (GOME) als eines von insgesamt sechs wissenschaftlichen Instrumenten an Bord des zweiten europaeischen Fernerkundungssatelliten (ERS-2) der ESA ins All gebracht. Das Ziel dieses Vorhabens ist es, die Genauigkeit der von GOME durchgefuehrten Messungen von sonnennormierter und absoluter Strahlungsdichte sowie der aus ihnen abgeleiteten Datenprodukte zu bewerten und zu verbessern. Dazu sollten die GOME-Daten mit Messungen von boden-, flugzeug- und satellitengestuetzten Systemen verglichen werden. Aus wissenschaftlichen Gruenden wird der Schwerpunkt auf Messungen bei mittleren und hohen Breitengraden in beiden Hemisphaeren liegen. Jedoch wurden im Laufe des Projektzeitraumes auch Regionen in Aequatornaehe untersucht. Im ersten Schritt sollen operationelle Datenprodukte von GOME validiert werden. Dieses sind Strahlungsmessungen (Spektren, Level1-Produkt) und Spurengas-Saeulendichten (Level2-Produkt). (orig.)

  14. Interpretation of ozone vertical profiles and their variations in the Northern hemisphere on the basis of GOME satellite data. Final report; Interpretation von Ozon-Vertikalprofilen und deren Variationen in der noerdlichen Hemisphaere unter Benutzung von GOME Satellitendaten. Abschlussbericht

    Eichmann, K.U.; Bramstedt, K.; Weber, M.; Rozanov, V.; Debeek, R.; Hoogen, R.; Burrows, J.P.

    2000-07-04

    Semiglobal ozone vertical profiles based on GOME measurements were established and evaluated systematically. GOME (Global Ozone Monitoring Experiment), carried by the ERS-2 satellite, is the first European passive optical sensor for long-term monitoring of ozone, other trace elements, and aerosols. Especially the vertical distribution of ozone in the Arctic region was measured and interpreted with a view to enhanced ozone degradation in the Arctic winter and spring seasons. Apart from the regional variations, also the time variations of the profiles are to provide further information on the dynamics and chemical processes in the polar vortex. The retrieval algorithm used for assessing the ozone vertical profiles, FURM (FUll Retrieval Method), is based on the GOMETRAN radiation transport model developed at Bremen university especially for evaluation of the GOME data. The GOME ozone profiles were validated with ozone probes and other satellite experiments. [German] Ziel des Projektes war eine systematische Bestimmung und Auswertung von semiglobalen Ozonvertikalprofilen aus den Messdaten von GOME. Das auf dem Satelliten ERS-2 fliegende Spektrometer GOME (Global Ozone Monitoring Experiment) ist der erste europaeische, passive, optische Sensor, der fuer Langzeitmessungen von Ozon, anderen Spurenstoffen und Aerosolen konzipiert wurde. Im Projekt wurde insbesondere die vertikale Verteilung von Ozon in der Arktis bestimmt und interpretiert hinsichtlich des verstaerkten Ozonabbaus im arktischen Winter und Fruehjahr. Neben der raeumlichen Variation sollen auch die zeitlichen Ablaeufe und Veraenderungen der Profile weitere Erkenntnise hinsichtlich der Dynamik und der chemischen Prozesse im Polarwirbel liefern. Der Retrievalalgorithmus zur Bestimmung des Ozonhoehenprofils, FURM (Full Retrieval Method) genannt, basiert auf dem Strahlungstransportmodell GOMETRAN, das an der Universitaet Bremen speziell fuer die Auswertung der Daten des GOME Instrumentes entwickelt wurde

  15. OCRA radiometric cloud fractions for GOME-2 on MetOp-A/B

    Lutz, Ronny; Loyola, Diego; Gimeno García, Sebastián; Romahn, Fabian

    2016-05-01

    This paper describes an approach for cloud parameter retrieval (radiometric cloud-fraction estimation) using the polarization measurements of the Global Ozone Monitoring Experiment-2 (GOME-2) onboard the MetOp-A/B satellites. The core component of the Optical Cloud Recognition Algorithm (OCRA) is the calculation of monthly cloud-free reflectances for a global grid (resolution of 0.2° in longitude and 0.2° in latitude) to derive radiometric cloud fractions. These cloud fractions will serve as a priori information for the retrieval of cloud-top height (CTH), cloud-top pressure (CTP), cloud-top albedo (CTA) and cloud optical thickness (COT) with the Retrieval Of Cloud Information using Neural Networks (ROCINN) algorithm. This approach is already being implemented operationally for the GOME/ERS-2 and SCIAMACHY/ENVISAT sensors and here we present version 3.0 of the OCRA algorithm applied to the GOME-2 sensors. Based on more than five years of GOME-2A data (April 2008 to June 2013), reflectances are calculated for ≈ 35 000 orbits. For each measurement a degradation correction as well as a viewing-angle-dependent and latitude-dependent correction is applied. In addition, an empirical correction scheme is introduced in order to remove the effect of oceanic sun glint. A comparison of the GOME-2A/B OCRA cloud fractions with colocated AVHRR (Advanced Very High Resolution Radiometer) geometrical cloud fractions shows a general good agreement with a mean difference of -0.15 ± 0.20. From an operational point of view, an advantage of the OCRA algorithm is its very fast computational time and its straightforward transferability to similar sensors like OMI (Ozone Monitoring Instrument), TROPOMI (TROPOspheric Monitoring Instrument) on Sentinel 5 Precursor, as well as Sentinel 4 and Sentinel 5. In conclusion, it is shown that a robust, accurate and fast radiometric cloud-fraction estimation for GOME-2 can be achieved with OCRA using polarization measurement devices (PMDs).

  16. Impact of using different ozone cross sections on ozone profile retrievals from Global Ozone Monitoring Experiment (GOME) ultraviolet measurements

    Liu, X.; Chance, K; C. E. Sioris; T. P. Kurosu

    2007-01-01

    We investigate the effect of using three different cross section data sets on ozone profile retrievals from Global Ozone Monitoring Experiment (GOME) ultraviolet measurements (289–307 nm, 326–337 nm). These include Bass-Paur, Brion, and GOME flight model cross sections (references below). Using different cross sections can significantly affect the retrievals, by up to 12 Dobson Units (DU, 1 DU=2.69×1016 molecules cm−2&l...

  17. Tropical tropospheric ozone columns from nadir retrievals of GOME-1/ERS-2, SCIAMACHY/Envisat, and GOME-2/MetOp-A (1996-2012)

    Leventidou, Elpida; Eichmann, Kai-Uwe; Weber, Mark; Burrows, John P.

    2016-07-01

    Tropical tropospheric ozone columns are retrieved with the convective cloud differential (CCD) technique using total ozone columns and cloud parameters from different European satellite instruments. Monthly-mean tropospheric column amounts [DU] are calculated by subtracting the above-cloud ozone column from the total column. A CCD algorithm (CCD_IUP) has been developed as part of the verification algorithm developed for TROPOspheric Monitoring Instrument (TROPOMI) on Sentinel 5-precursor (S5p) mission, which was applied to GOME/ERS-2 (1995-2003), SCIAMACHY/Envisat (2002-2012), and GOME-2/MetOp-A (2007-2012) measurements. Thus a unique long-term record of monthly-mean tropical tropospheric ozone columns (20° S-20° N) from 1996 to 2012 is now available. An uncertainty estimation has been performed, resulting in a tropospheric ozone column uncertainty less than 2 DU ( ozone columns by about 8 DU, while SCIAMACHY and GOME are in good agreement. Validation with Southern Hemisphere ADditional OZonesondes (SHADOZ) data shows that tropospheric ozone columns from the CCD_IUP technique and collocated integrated ozonesonde profiles from the surface up to 200 hPa are in good agreement with respect to range, interannual variations, and variances. Biases within ±5 DU and root-mean-square (RMS) deviation of less than 10 DU are found for all instruments. CCD comparisons using SCIAMACHY data with tropospheric ozone columns derived from limb/nadir matching have shown that the bias and RMS deviation are within the range of the CCD_IUP comparison with the ozonesondes. The 17-year dataset can be helpful for evaluating chemistry models and performing climate change studies.

  18. Comparison of Model-simulated Tropospheric NO2 over China with GOME-satellite Data

    VAN AARDENNE JOHN; JIANZHONG Ma

    2006-01-01

    Tropospheric NO2 column densities over China simulated with a regional model using different emission inventory input are compared with Global Ozone Monitoring Experiment (GOME) satellite data. These emission inventories include (i) emission estimates for the year 1995 from the Emission Database for Global Atmospheric Research (EDGAR), (ii) regional emission inventory used in the Transport and Chemical Evolution over the Pacific (TRACE-P) program with emission estimates for the year 2000 a...

  19. Total column water vapour measurements from GOME-2 MetOp-A and MetOp-B

    M. Grossi

    2014-03-01

    Full Text Available The knowledge of the total column water vapour (TCWV global distribution is fundamental for climate analysis and weather monitoring. In this work, we present the retrieval algorithm used to derive the operational TCWV from the GOME-2 sensors and perform an extensive inter-comparison and validation in order to estimate their absolute accuracy and long-term stability. We use the recently reprocessed data sets retrieved by the GOME-2 instruments aboard EUMETSAT's MetOp-A and MetOp-B satellites and generated by DLR in the framework of the O3M-SAF using the GOME Data Processor (GDP version 4.7. The retrieval algorithm is based on a classical Differential Optical Absorption Spectroscopy (DOAS method and combines H2O/O2 retrieval for the computation of the trace gas vertical column density. We introduce a further enhancement in the quality of the H2O column by optimizing the cloud screening and developing an empirical correction in order to eliminate the instrument scan angle dependencies. We evaluate the overall consistency between about 8 months measurements from the newer GOME-2 instrument on the MetOp-B platform with the GOME-2/MetOp-A data in the overlap period. Furthermore, we compare GOME-2 results with independent TCWV data from ECMWF and with SSMIS satellite measurements during the full period January 2007–August 2013 and we perform a validation against the combined SSM/I + MERIS satellite data set developed in the framework of the ESA DUE GlobVapour project. We find global mean biases as small as ± 0.03 g cm−2 between GOME-2A and all other data sets. The combined SSM/I-MERIS sample is typically drier than the GOME-2 retrievals (−0.005 g cm−2, while on average GOME-2 data overestimate the SSMIS measurements by only 0.028 g cm−2. However, the size of some of these biases are seasonally dependent. Monthly average differences can be as large as 0.1 g cm−2, based on the analysis against SSMIS measurements, but are not as evident in

  20. Seven years of global retrieval of cloud properties using space-borne data of GOME-1

    L. Lelli

    2011-08-01

    Full Text Available We present a global and regional multi-annual (1996–2002 analysis of cloud properties (spherical albedo, optical thickness and top height derived using measurements from the GOME-1 instrument onboard the ESA ERS-2 space platform. We focus on cloud top height (CTH, which is obtained from top-of-atmosphere backscattered solar light measurements in the O2 A-band using the Semi-Analytical CloUd Retrieval Algorithm SACURA. The physical framework relies on the asymptotic equations of radiative transfer. The dataset has been validated against independent ground- and satellite-based retrievals and is aimed to support ozone and trace-gases studies as well as to create a robust long-term climatology together with SCIAMACHY and GOME-2 ensuing retrievals. We observed the El Niño Southern Oscillation anomaly in the 1997–1998 record through CTH values over Pacific Ocean. Analytical forms of probability density functions of seasonal CTH are proposed for parameterizations in climate modeling. The global average CTH as derived from GOME-1 is 7.0 ± 1.18 km.

  1. Tropospheric NO2 columns: a comparison between model and retrieved data from GOME measurements

    A. Lauer

    2002-01-01

    Full Text Available Tropospheric NO2 plays a variety of significant roles in atmospheric chemistry. In the troposphere it is one of the most significant precursors of photochemical ozone (O3 production and nitric acid (HNO3. In this study tropospheric NO2 columns were calculated by the fully coupled chemistry-climate model ECHAM4.L39(DLR/CHEM. These have been compared with tropospheric NO2 columns, retrieved using the tropospheric excess method from measurements by the Global Ozone Monitoring Experiment (GOME of up-welling earthshine radiance and the extraterrestrial irradiance. GOME is part of the core payload of the second European Research Satellite (ERS-2. For this study the first five years of GOME measurements have been used. The period of five years of observational data is sufficiently long to facilitate for the first time a comparison based on climatological averages with global coverage, focussing on the geographical distribution of the tropospheric NO2. A new approach of analysing regional differences (i.e. on continental scales by calculating individual averages for different environments provides more detailed information about specific NOx sources and of their seasonal variations. The results obtained enable the validity of the model NO2 source distribution and the assumptions used to separate tropospheric and stratospheric parts of the NO2 column amount from the satellite measurements to be investigated.

  2. Tropospheric NO2 columns: a comparison between model and retrieved data from GOME measurements

    A. Richter

    2001-12-01

    Full Text Available Tropospheric NO2 plays a variety of significant roles in atmospheric chemistry. In the troposphere it is one of the most significant precursors of photochemical ozone (O3 production and nitric acid (HNO3. In this study tropospheric NO2 columns were calculated by the fully coupled chemistry-climate model ECHAM4.L39(DLR/CHEM. These have been compared with tropospheric NO2 columns, retrieved using the tropospheric excess method from measurements by the Global Ozone Monitoring Experiment (GOME of up-welling earthshine irradiance and the extraterrestrial radiance. GOME is part of the core payload of the second European Research Satellite (ERS-2. For this study the first five years of GOME measurements have been used. The period of five years of observational data is sufficient to enable a comparison based on climatological averages and with global coverage, focussing on the geographical distribution of the tropospheric NO2, for the first time. A new approach of analysing regional differences (i.e. on continental scales by calculating individual averages for different environments provides more detailed information about specific NOx sources and of their seasonal variations. The results obtained enable the validity of the model NO2 source distribution and the assumptions used to separate tropospheric and stratospheric parts of the NO2 column amount from the satellite measurements to be investigated.

  3. Seven years of global retrieval of cloud properties using space-borne data of GOME

    L. Lelli

    2012-07-01

    Full Text Available We present a global and regional multi-annual (June 1996–May 2003 analysis of cloud properties (spherical cloud albedo – CA, cloud optical thickness – COT and cloud top height – CTH of optically thick (COT > 5 clouds, derived using measurements from the GOME instrument on board the ESA ERS-2 space platform. We focus on cloud top height, which is obtained from top-of-atmosphere backscattered solar light measurements in the O2 A-band using the Semi-Analytical CloUd Retrieval Algorithm SACURA. The physical framework relies on the asymptotic equations of radiative transfer. The dataset has been validated against independent ground- and satellite-based retrievals and is aimed to support trace-gases retrievals as well as to create a robust long-term climatology together with SCIAMACHY and GOME-2 ensuing retrievals. We observed the El Niño-Southern Oscillation anomaly in the 1997–1998 record through CTH values over the Pacific Ocean. The global average CTH as derived from GOME is 5.6 ± 3.2 km, for a corresponding average COT of 19.1 ± 13.9.

  4. Development of an OClO Slant Column Product for the GOME-2 Sensors

    Richter, Andreas; Wittrock, Folkard; Burrows, John P.

    2016-04-01

    Stratospheric ozone depletion by catalytic reactions involving halogens is one of the most prominent examples of anthropogenic impacts on the atmosphere. In spite of the rapid and successful international action to reduce emissions of CFCs and other ozone depleting substances leading to the Montreal Protocol and its amendments, ozone depletion in polar spring is still observed in both hemispheres on a regular basis. For the coming years, slow ozone recovery is expected but individual years will still see very low ozone columns depending on meteorology and possible interactions with climate change. Monitoring of both ozone and ozone depleting substances in the stratosphere remains a priority to ensure that the predicted reduction in halogen levels and recovery of ozone columns is taking place as predicted. One way to observe stratospheric chlorine activation is by measurements of OClO which can be detected by UV/visible remote sensing from the ground and from satellite. While the link between OClO levels and chlorine activation is complicated by the fact that a) OClO is not directly involved in ozone depletion but is produced by reaction of BrO and ClO and b) is rapidly photolysed at daylight, the long existing data series from both ground-based and satellite observations makes it an interesting tracer of chlorine activation. The GOME-2 instruments on the MetOp series of satellites are nadir viewing UV/vis spectrometers having the spectral coverage and resolution needed for Differential Optical Absorption Spectroscopy retrievals of OClO. With their combined lifetime of more than 15 years, they can provide a long-term data set. However, previous attempts to create an OClO product for GOME-2 suffered from large scatter in the OClO data and time-dependent offsets. Here we present an improved OClO slant column retrieval for the two instruments GOME2-A and GOME2-B. The data is shown to be of similar quality as for earlier instruments such as SCIAMACHY, and is consistent

  5. Evaluating a new homogeneous total ozone climate data record from GOME/ERS-2, SCIAMACHY/Envisat, and GOME-2/MetOp-A

    Koukouli, M. E.; Lerot, C.; Granville, J.; Goutail, F.; Lambert, J.-C.; Pommereau, J.-P.; Balis, D.; Zyrichidou, I.; Van Roozendael, M.; Coldewey-Egbers, M.; Loyola, D.; Labow, G.; Frith, S.; Spurr, R.; Zehner, C.

    2015-12-01

    The European Space Agency's Ozone Climate Change Initiative (O3-CCI) project aims at producing and validating a number of high-quality ozone data products generated from different satellite sensors. For total ozone, the O3-CCI approach consists of minimizing sources of bias and systematic uncertainties by applying a common retrieval algorithm to all level 1 data sets, in order to enhance the consistency between the level 2 data sets from individual sensors. Here we present the evaluation of the total ozone products from the European sensors Global Ozone Monitoring Experiment (GOME)/ERS-2, SCIAMACHY/Envisat, and GOME-2/MetOp-A produced with the GOME-type Direct FITting (GODFIT) algorithm v3. Measurements from the three sensors span more than 16 years, from 1996 to 2012. In this work, we present the latest O3-CCI total ozone validation results using as reference ground-based measurements from Brewer and Dobson spectrophotometers archived at the World Ozone and UV Data Centre of the World Meteorological Organization as well as from UV-visible differential optical absorption spectroscopy (DOAS)/Système D'Analyse par Observations Zénithales (SAOZ) instruments from the Network for the Detection of Atmospheric Composition Change. In particular, we investigate possible dependencies in these new GODFIT v3 total ozone data sets with respect to latitude, season, solar zenith angle, and different cloud parameters, using the most adequate type of ground-based instrument. We show that these three O3-CCI total ozone data products behave very similarly and are less sensitive to instrumental degradation, mainly as a result of the new reflectance soft-calibration scheme. The mean bias to the ground-based observations is found to be within the 1 ± 1% level for all three sensors while the near-zero decadal stability of the total ozone columns (TOCs) provided by the three European instruments falls well within the 1-3% requirement of the European Space Agency's Ozone Climate Change

  6. Chlorophyll induced fluorescence retrieved from GOME2 for improving gross primary productivity estimates of vegetation

    van Leth, Thomas C.; Verstraeten, Willem W.; Sanders, Abram F. J.

    2014-05-01

    Mapping terrestrial chlorophyll fluorescence is a crucial activity to obtain information on the functional status of vegetation and to improve estimates of light-use efficiency (LUE) and global primary productivity (GPP). GPP quantifies carbon fixation by plant ecosystems and is therefore an important parameter for budgeting terrestrial carbon cycles. Satellite remote sensing offers an excellent tool for investigating GPP in a spatially explicit fashion across different scales of observation. The GPP estimates, however, still remain largely uncertain due to biotic and abiotic factors that influence plant production. Sun-induced fluorescence has the ability to enhance our knowledge on how environmentally induced changes affect the LUE. This can be linked to optical derived remote sensing parameters thereby reducing the uncertainty in GPP estimates. Satellite measurements provide a relatively new perspective on global sun-induced fluorescence, enabling us to quantify spatial distributions and changes over time. Techniques have recently been developed to retrieve fluorescence emissions from hyperspectral satellite measurements. We use data from the Global Ozone Monitoring Instrument 2 (GOME2) to infer terrestrial fluorescence. The spectral signatures of three basic components atmospheric: absorption, surface reflectance, and fluorescence radiance are separated using reference measurements of non-fluorescent surfaces (desserts, deep oceans and ice) to solve for the atmospheric absorption. An empirically based principal component analysis (PCA) approach is applied similar to that of Joiner et al. (2013, ACP). Here we show our first global maps of the GOME2 retrievals of chlorophyll fluorescence. First results indicate fluorescence distributions that are similar with that obtained by GOSAT and GOME2 as reported by Joiner et al. (2013, ACP), although we find slightly higher values. In view of optimizing the fluorescence retrieval, we will show the effect of the references

  7. Overview of the O3M SAF GOME-2 operational atmospheric composition and UV radiation data products and data availability

    S. Hassinen

    2015-07-01

    Full Text Available The three GOME-2 instruments will provide unique and long data sets for atmospheric research and applications. The complete time period will be 2007–2022, including the period of ozone depletion as well as the beginning of ozone layer recovery. Besides ozone chemistry, the GOME-2 products are important e.g. for air quality studies, climate modeling, policy monitoring and hazard warnings. The heritage for GOME-2 is in the ERS/GOME and Envisat/SCIAMACHY instruments. The current Level 2 (L2 data cover a wide range of products such as trace gas columns (NO2, BrO, H2CO, H2O, SO2, tropospheric columns of NO2, total ozone columns and vertical ozone profiles in high and low spatial resolution, absorbing aerosol indices from the main science channels as well as from the polarization channels (AAI, AAI-PMD, Lambertian-equivalent reflectivity database, clear-sky and cloud-corrected UV indices and surface UV fields with different weightings and photolysis rates. The Ozone Monitoring and Atmospheric Composition Satellite Application Facility (O3M SAF processing and data dissemination is operational and running 24/7. Data quality is quarantined by the detailed review processes for the algorithms, validation of the products as well as by a continuous quality monitoring of the products and processing. This is an overview paper providing the O3M SAF project background, current status and future plans to utilization of the GOME-2 data. An important focus is the provision of summaries of the GOME-2 products including product principles and validation examples together with the product sample images. Furthermore, this paper collects the references to the detailed product algorithm and validation papers.

  8. Hydrocarbon Emissions Constrained By Formaldehyde Column Measurements from Gome-2 and OMI

    Stavrakou, T.; Muller, J. F.; Bauwens, M.; De Smedt, I.; Van Roozendael, M.; De Maziere, M.; Vigouroux, C.

    2014-12-01

    The vertical columns of formaldehyde retrieved from the spaceborne instruments GOME2 and OMI are used to constrain the biogenic, pyrogenic and anthropogenic emissions of formaldehyde precursors NMVOC at the global scale. To this end, those emissions are varied and optimized in the (updated) IMAGESv2 model. The adjoint model technique is used to minimize the bias of the model with observations from either GOME2 or OMI. The optimisation is performed on a monthly basis at the model resolution (2°x2.5°). The a priori biogenic emissions are provided by the MEGAN-ECMWF-v2 inventory for isoprene and from a previous optimization of methanol emissions based on IASI columns. Biomass burning and anthropogenic emissions are taken from GFEDv3 and from a combination of the RETRO global inventory with the regional inventory REASv2.Given the different local overpass times of GOME2 (9h30 LT) and OMI (13h40 LT), the factors which might affect the diurnal cycle of formaldehyde in the model (chemistry, diurnal profile of emissions, mixing) are examined through sensitivity calculations. The simulated diurnal cycle is evaluated against ground-based measurements obtained by either the MAX-DOAS technique (in Europe, China, and Africa) or by FTIR (in the Indian Ocean). The agreement between simulated and observed normalized columns is found to be generally better in the summer (with a clear afternoon maximum at mid-latitude sites) than in the winter.Both optimizations infer a reduction of the global biogenic emissions of isoprene (by 10-15%), which is largest (up to a factor of 2) over Eastern U.S. according to GOME2 and over Western Amazonia according to OMI. Those reductions and evaluated by comparisons with arcraft observations for different years (ARCTAS and INTEX-A). Northern Australia, Southern China and Northern Africa are also regions where both sensors indicate an overestimation of MEGAN. Biomass burning emissions appear to be likewise overestimated in Central Canada

  9. Consistent interpretation of ground based and GOME BrO slant column data

    Mueller, R. W.; Bovensmann, H.; Kaiser, J. W.; Richter, A.; Rozanov, A.; Wittrock, F.; Burrows, J. P.

    Model computations of slant column densities (SCD) enable the comparison between ground based and satellite based absorption measurements of scattered light and are therefore a good basis to investigate the presence of tropospheric BrO amounts. In this study ground based zenith sky and GOME nadir measurements of BrO SCD are compared with simulations for the 19-21 March 1997 at Ny-Ålesund. The vertical columns of tropospheric BrO amounts are estimated to be in the range 4 ±0.8 ∗ 10 13 [molecules/cm 2] for the investigated period and location.

  10. Formaldehyde and nitrogen dioxide over the remote Western Pacific Ocean: SCIAMACHY and GOME-2 validation

    E. Peters

    2012-06-01

    Full Text Available In October 2009, ship-borne Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS measurements were performed during the TransBrom campaign over the Western Pacific Ocean (≈40° N to −207° S. Vertical tropospheric trace gas columns and profiles of nitrogen dioxide (NO2 and formaldehyde (HCHO as well as stratospheric NO2 columns were retrieved in order to validate corresponding measurements from the GOME-2 and SCIAMACHY satellite instruments and to estimate tropospheric background concentrations of these trace gases.

    All instruments reproduced the same characteristic latitude-dependent shape of stratospheric NO2. SCIAMACHY and GOME-2 data differ by about 1% from each other while yielding lower vertical columns than MAX-DOAS morning values as a consequence of measurement time and stratospheric NO2 diurnal cycle. At low latitudes, an increase of 8.7 ± 0.5 × 1013 molec cm−2 h−1 of stratospheric NO2 was estimated from MAX-DOAS data.

    Tropospheric NO2 was above the detection limit only in regions of higher anthropogenic impact (ship traffic, transport of pollution from land. A background column of 1.3 × 1014 molec cm−2 (or roughly 50 ppt BL concentration can be estimated as upper limit for the remote ocean, which is in agreement with GOME-2 monthly mean values. In the marine boundary layer close to the islands of Hokkaido and Honshu, up to 0.8 ppbv were retrieved close to the surface.

    Background HCHO concentrations over the remote ocean exhibit a diurnal cycle with maximum values (depending strongly on weather conditions of 4 × 1015 molec cm−2 for the vertical column at noon-time. Corresponding peak concentrations of up to 1.1 ppbv were retrieved in altitudes of 400–600 m around noon while maximum concentrations in the evening are close to the ground

  11. Seven years of global retrieval of cloud properties using space-borne data of GOME

    L. Lelli; Kokhanovsky, A. A.; V. V. Rozanov; M. Vountas; Sayer, A. M.; Burrows, J.P.

    2012-01-01

    We present a global and regional multi-annual (June 1996–May 2003) analysis of cloud properties (spherical cloud albedo – CA, cloud optical thickness – COT and cloud top height – CTH) of optically thick (COT > 5) clouds, derived using measurements from the GOME instrument on board the ESA ERS-2 space platform. We focus on cloud top height, which is obtained from top-of-atmosphere backscattered solar light measurements in the O2 A-band using the Semi-Analytical CloUd ...

  12. Seven years of global retrieval of cloud properties using space-borne data of GOME-1

    L. Lelli; Kokhanovsky, A. A.; V. V. Rozanov; M. Vountas; Sayer, A. M.; Burrows, J.P.

    2011-01-01

    We present a global and regional multi-annual (1996–2002) analysis of cloud properties (spherical albedo, optical thickness and top height) derived using measurements from the GOME-1 instrument onboard the ESA ERS-2 space platform. We focus on cloud top height (CTH), which is obtained from top-of-atmosphere backscattered solar light measurements in the O2 A-band using the Semi-Analytical CloUd Retrieval Algorithm SACURA. The physical framework relies on the asymptotic e...

  13. A fast H2O total column density product from GOME – Validation with in-situ aircraft measurements

    T. Wagner

    2003-01-01

    Full Text Available Atmospheric water vapour is the most important greenhouse gas which is responsible for about 2/3 of the natural greenhouse effect, therefore changes in atmospheric water vapour in a changing climate (the water vapour feedback is subject to intense debate. H2O is also involved in many important reaction cycles of atmospheric chemistry, e.g. in the production of the OH radical. Thus, long time series of global H2O data are highly required. Since 1995 the Global Ozone Monitoring Experiment (GOME continuously observes atmospheric trace gases. In particular it has been demonstrated that GOME as a nadir looking UV/vis-instrument is sensitive to many tropospheric trace gases. Here we present a new, fast H2O algorithm for the retrieval of vertical column densities from GOME measurements. In contrast to existing H2O retrieval algorithms it does not depend on additional information like e.g. the climatic zone, aerosol content or ground albedo. It includes an internal cloud-, aerosol-, and albedo correction which is based on simultaneous observations of the oxygen dimer O4. From sensitivity studies using atmospheric radiative modelling we conclude that our H2O retrieval overestimates the true atmospheric H2O vertical column density (VCD by about 4% for clear sky observations in the tropics and sub-tropics, while it can lead to an underestimation of up to -18% in polar regions. For measurements over (partly cloud covered ground pixels, however, the true atmospheric H2O VCD might be in general systematically underestimated. We compared the GOME H2O VCDs to ECMWF model data over one whole GOME orbit (extending from the Arctic to the Antarctic including also totally cloud covered measurements. The correlation of the GOME observations and the model data yield the following results: a slope of 0.96 (r2 = 0.86 and an average bias of 5%. Even for measurements with large cloud fractions between 50% and 100% an average underestimation of only -18% was found. This

  14. Pole-to-pole validation of GOME WFDOAS total ozone with groundbased data

    M. Weber

    2004-10-01

    Full Text Available This paper summarises the validation of GOME total ozone retrieved using the weighting function differential optical absorption spectroscopy (WFDOAS algorithm Version 1.0. This algorithm has been described in detail in a companion paper by Coldewey-Egbers et al. (2004. The WFDOAS results have been compared with selected ground-based measurements from the WOUDC (World Ozone and UV Radiation Data Centre that collects total ozone measurements from a global network of stations covering all seasons. From the global validation excellent agreement between WFDOAS and ground data was found and on average agree to within ±1%. Very little seasonal variations in the observed differences are observed. In the polar region and at high solar zenith angles, however, a positive bias varying between 5 and 8% is found. Very few stations carry out simultaneous measurements by Brewer and Dobson spectrometers over an extended period (three years or more. Simultaneous Brewer and Dobson measurements from Hradec Kralove, Czech Republic (50.2° N, 15.8° E and Hohenpeissenberg, Germany (47.8° N, 11.0° E covering the period 1996–1999 have been compared with our GOME results. Agreement with Brewers are generally better than with the simultaneous Dobson measurements and this may be explained by the neglect of stratospheric (ozone temperature correction in the standard ozone retrieval from the ground.

  15. The GOME-type Total Ozone Essential Climate Variable (GTO-ECV data record from the ESA Climate Change Initiative

    M. Coldewey-Egbers

    2015-05-01

    Full Text Available We present the new GOME-type Total Ozone Essential Climate Variable (GTO-ECV data record which has been created within the framework of the European Space Agency's Climate Change Initiative (ESA-CCI. Total ozone column observations – based on the GOME-type Direct Fitting version 3 algorithm – from GOME (Global Ozone Monitoring Experiment, SCIAMACHY (SCanning Imaging Absorption SpectroMeter for Atmospheric CHartographY, and GOME-2 have been combined into one homogeneous time series, thereby taking advantage of the high inter-sensor consistency. The data record spans the 15-year period from March 1996 to June 2011 and it contains global monthly mean total ozone columns on a 1° × 1° grid. Geophysical ground-based validation using Brewer, Dobson, and UV-visible instruments has shown that the GTO-ECV level 3 data record is of the same high quality as the equivalent individual level 2 data products that constitute it. Both absolute agreement and long-term stability are excellent with respect to the ground-based data, for almost all latitudes apart from a few outliers which are mostly due to sampling differences between the level 2 and level 3 data. We conclude that the GTO-ECV data record is valuable for a variety of climate applications such as the long-term monitoring of the past evolution of the ozone layer, trend analysis and the evaluation of Chemistry–Climate Model simulations.

  16. The GOME-type Total Ozone Essential Climate Variable (GTO-ECV) data record from the ESA Climate Change Initiative

    Coldewey-Egbers, M.; Loyola, D. G.; Koukouli, M.; Balis, D.; Lambert, J.-C.; Verhoelst, T.; Granville, J.; van Roozendael, M.; Lerot, C.; Spurr, R.; Frith, S. M.; Zehner, C.

    2015-09-01

    We present the new GOME-type Total Ozone Essential Climate Variable (GTO-ECV) data record which has been created within the framework of the European Space Agency's Climate Change Initiative (ESA-CCI). Total ozone column observations - based on the GOME-type Direct Fitting version 3 algorithm - from GOME (Global Ozone Monitoring Experiment), SCIAMACHY (SCanning Imaging Absorption SpectroMeter for Atmospheric CHartographY), and GOME-2 have been combined into one homogeneous time series, thereby taking advantage of the high inter-sensor consistency. The data record spans the 15-year period from March 1996 to June 2011 and it contains global monthly mean total ozone columns on a 1°× 1° grid. Geophysical ground-based validation using Brewer, Dobson, and UV-visible instruments has shown that the GTO-ECV level 3 data record is of the same high quality as the equivalent individual level 2 data products that constitute it. Both absolute agreement and long-term stability are excellent with respect to the ground-based data, for almost all latitudes apart from a few outliers which are mostly due to sampling differences between the level 2 and level 3 data. We conclude that the GTO-ECV data record is valuable for a variety of climate applications such as the long-term monitoring of the past evolution of the ozone layer, trend analysis and the evaluation of chemistry-climate model simulations.

  17. Overview of the O3M SAF GOME-2 operational atmospheric composition and UV radiation data products and data availability

    Hassinen, S.; Balis, D.; Bauer, H.; Begoin, M.; Delcloo, A.; Eleftheratos, K.; Gimeno Garcia, S.; Granville, J.; Grossi, M.; Hao, N.; Hedelt, P.; Hendrick, F.; Hess, M.; Heue, K.-P.; Hovila, J.; Jønch-Sørensen, H.; Kalakoski, N.; Kauppi, A.; Kiemle, S.; Kins, L.; Koukouli, M. E.; Kujanpää, J.; Lambert, J.-C.; Lang, R.; Lerot, C.; Loyola, D.; Pedergnana, M.; Pinardi, G.; Romahn, F.; van Roozendael, M.; Lutz, R.; De Smedt, I.; Stammes, P.; Steinbrecht, W.; Tamminen, J.; Theys, N.; Tilstra, L. G.; Tuinder, O. N. E.; Valks, P.; Zerefos, C.; Zimmer, W.; Zyrichidou, I.

    2016-02-01

    The three Global Ozone Monitoring Experiment-2 instruments will provide unique and long data sets for atmospheric research and applications. The complete time period will be 2007-2022, including the period of ozone depletion as well as the beginning of ozone layer recovery. Besides ozone chemistry, the GOME-2 (Global Ozone Monitoring Experiment-2) products are important e.g. for air quality studies, climate modelling, policy monitoring and hazard warnings. The heritage for GOME-2 is in the ERS/GOME and Envisat/SCIAMACHY instruments. The current Level 2 (L2) data cover a wide range of products such as ozone and minor trace gas columns (NO2, BrO, HCHO, H2O, SO2), vertical ozone profiles in high and low spatial resolution, absorbing aerosol indices, surface Lambertian-equivalent reflectivity database, clear-sky and cloud-corrected UV indices and surface UV fields with different weightings and photolysis rates. The Satellite Application Facility on Ozone and Atmospheric Chemistry Monitoring (O3M SAF) processes and disseminates data 24/7. Data quality is guaranteed by the detailed review processes for the algorithms, validation of the products as well as by a continuous quality monitoring of the products and processing. This paper provides an overview of the O3M SAF project background, current status and future plans for the utilisation of the GOME-2 data. An important focus is the provision of summaries of the GOME-2 products including product principles and validation examples together with sample images. Furthermore, this paper collects references to the detailed product algorithm and validation papers.

  18. Monitoring of Volcanic Eruptions and Determination of SO2 Plume Height from GOME-2 Measurements

    Rix, M.; Valks, P.; Loyola, D.; Maerker, C.; Seidenberger, K.; van Gent, J.; van Roozendael, M.; Spurr, R.; Hao, N.; Emmandi, S.; Zimmer, W.

    2010-12-01

    Satellite-based remote sensing measurements of atmospheric sulphur dioxide (SO2) provide valuable information on anthropogenic pollution and volcanic activity. Sensors like GOME-2 on MetOp-A make it possible to monitor SO2 emissions on a global scale and daily basis. SO2 total column amounts are retrieved in near-real time using the UV range of backscattered sunlight making it possible to detect and track volcanic eruption plumes as a valuable tool for aviation warning. For aviation safety the correct determination of the plume height is a central issue. Therefore a novel method has been developed for the determination of the plume height in near-real time based on the operational DOAS retrieval combined with an iterative look-up table (LUT) approach. The method has been applied to the eruption of Eyjafjöll volcano, April - May 2010, and to the eruption of Kilauea, July 2008.

  19. Application of the Spectral Structure Parameterization technique: retrieval of total water vapor columns from GOME

    R. Lang

    2003-01-01

    Full Text Available We use a recently proposed spectral sampling technique for measurements of atmospheric transmissions called the Spectral Structure Parameterization (SSP in order to retrieve total water vapor columns (WVC from reflectivity spectra measured by the Global Ozone Monitoring Experiment (GOME. SSP provides a good compromise between efficiency and speed when performing retrievals on highly structured spectra of narrow-band absorbers like water vapor. We show that SSP can be implemented in a radiative transfer scheme which treats both direct-path absorption and absorption by singly-scattered light directly. For the retrieval we exploit a ro-vibrational overtone band of water vapor located in the visible around 590 nm. We compare our results to independent values given by the data assimilation model of ECMWF. In addition, results are compared to those obtained from the more accurate, but more computationally expensive, Optical Absorption Coefficient Spectroscopy (OACS.

  20. Monitoring the Bardarbunga eruption using GOME-2/Metop-A & -B

    Hedelt, Pascal; Valks, Pieter; Loyola, Diego

    2015-04-01

    We will present here the results of the Bardarbunga eruption monitored by the GOME-2 instrument aboard MetOp-A & -B. After increased seismic activity in August, the Icelandic volcano Bardarbunga (Bárðarbunga) erupted on 31 August 2014. Since 1 September the GOME-2 instruments aboard the MetOp-A and -B satellites detect a continuous emission of sulphur-dioxide (SO2) emitted from the Holuhraun fissure at the flanks of the Bardarbunga volcano. At the beginning the emitted SO2 was mainly transported to the north-eastern direction over Scandinavia and Russia. However, on September 22 an SO2 cloud was even moving over Europe and could be detected at the Hohenpeissenberg and Schneefernerhaus observatories. SO2 emissions are a good indicator for volcanic activity, since besides weak anthropogenic emissions there are no other known sources for atmospheric SO2, which can cause respiratory problems in the local population and the aircraft passengers. Furthermore in form of acid rain it increases the oxidation of aircraft components. It was found that for some volcanic eruptions SO2 can be a good proxy for the much harder to detect volcanic ash. Volcanic ash can be hazardous not only for the local population but also for aviation since it can cause total engine failure if it melts and then congeals in the engine. Furthermore ash is highly abrasive to engine turbine vanes and propellers. Under the leadership of IMF, DLR-EOC provides operational trace gas measurements, including total SO2 columns, in near-real-time (i.e., within 2 hours of recording) in the framework of EUMETSAT's Satellite Application Facility on Ozone and Atmospheric Chemistry Monitoring (O3M-SAF).

  1. GOME assimilated NO2 fields for scientific users and model validation

    Boersma, K. F.; Eskes, H. J.

    2003-04-01

    Nadir-viewing satellite instruments such as GOME on ERS-2 have proven that it is possible to produce quantitative estimates of tropospheric NO2 columns, including the boundary layer. GOME observes several key species of tropospheric chemistry, such as O3, NO2, HCHO, BrO and SO2. These data sets contain important information on aspects like fossil fuel burning emissions, natural hydrocarbon emissions, biomass burning, NOx produced by lightning, and volcano emissions. The GOA project aims to provide long-term series of high level assimilated data to scientific users. In our paper, we focus on three important aspects of delivering high-quality NO2 columns: (1) the retrieval method, (2) the concept of the averaging kernel in DOAS, and (3) the error analysis. (1) Quantitative estimates of tropospheric NO2 columns are obtained using the three-step DOAS method that obtains a spectrally fitted slant column density, isolates a stratospheric component of the total slant column, and converts the residual tropospheric slant column into a tropospheric vertical column via a tropospheric air-mass factor. (2) DOAS column retrieval of NO2 is dependent on an a priori tracer profile. The air-mass factor calculation in DOAS accounts for the altitude-dependent sensitivity of the measurement to tracer concentrations at all altitudes. This sensitivity -also known as 'scattering weights'- is weighted with the assumed tracer profile to constitute the averaging kernel, that provides the relation between the retrieved quantities and the true tracer profile. (3) DOAS column retrieval of tropospheric NO2 has to contend with a multitude uncertainties related to the satellite instrument and to a priori model parameters. We will present a detailed quantitative error analysis, discussing errors due to the satellite instrument (fitting errors), errors in the estimate of the stratospheric column, and errors in the a priori model parameters (amongst others due to uncertainty in the assumed profile

  2. Comparison and evaluation of modelled and GOME measurement derived tropospheric NO2 columns over Western and Eastern Europe

    I. B. Konovalov

    2005-01-01

    Full Text Available We present the results of a first comparison of the tropospheric NO2 column amounts derived from the measurements of the Global Ozone Monitoring Experiment (GOME with the simulated data from a European scale chemistry transport model (CTM which is distinct from existing global scale CTMs in higher horizontal resolution and more detailed description of the boundary layer processes and emissions. We employ, on the one hand, the newly developed extended version of the CHIMERE CTM, which covers both Western and Eastern Europe, and, on the other hand, the most recent version (Version 2 of GOME measurement based data-products, developed at the University of Bremen. We evaluate our model with the data from ground based monitoring of ozone and verify that it has a sufficiently high level of performance, which is expected for a state-of-the-art continental scale CTM. The major focus of the study is on a systematic statistical analysis and a comparison of spatial variability of the tropospheric NO2 columns simulated with CHIMERE and derived from GOME measurements. The analysis is performed separately for Western and Eastern Europe using the data for summer months of 1997 and 2001. In this way, we obtain useful information on the nature and magnitudes of uncertainties of spatial distributions of the considered data. Specifically, for Western Europe, it is found that the uncertainties of NO2 columns from GOME and CHIMERE are predominantly of the multiplicative character, and that the mean relative random (multiplicative errors of the GOME measurement derived and simulated data averaged over the summer seasons considered do not exceed 23% and 32%, respectively. The mean absolute (additive errors of both kinds of the data are estimated to be less than 3x1014mol/cm2. In Eastern Europe, the uncertainties have more complex character, and the separation between their multiplicative and additive parts is not sufficiently unambiguous. It is found, however, that the

  3. Comparison of total water vapor column from GOME-2 on MetOp-A against ground-based GPS measurements at the Iberian Peninsula.

    Román, R; Antón, M; Cachorro, V E; Loyola, D; Ortiz de Galisteo, J P; de Frutos, A; Romero-Campos, P M

    2015-11-15

    Water vapor column (WVC) obtained by GOME-2 instrument (GDP-4.6 version) onboard MetOp-A satellite platform is compared against reference WVC values derived from GPS (Global Positioning System) instruments from 2007 to 2012 at 21 places located at Iberian Peninsula. The accuracy and precision of GOME-2 to estimate the WVC is studied for different Iberian Peninsula zones using the mean (MBE) and the standard deviation (SD) of the GOME-2 and GPS differences. A direct comparison of all available data shows an overestimation of GOME-2 compared to GPS with a MBE of 0.7 mm (10%) and a precision quantified by a SD equals to 4.4mm (31%). South-Western zone presents the highest overestimation with a MBE of 1.9 mm (17%), while Continental zone shows the lowest SD absolute value (3.3mm) due mainly to the low WVC values reached at this zone. The influence of solar zenith angle (SZA), cloud fraction (CF), and the type of surface and its albedo on the differences between GOME-2 and GPS is analyzed in detail. MBE and SD increase when SZA increases, but MBE decreases (taking negative values) when CF increases and SD shows no significant dependence on CF. Under cloud-free conditions, the differences between WVC from GOME-2 and GPS are within the WVC error given by GOME-2. The changes of MBE and SD on Surface Albedo are not so evident, but MBE slightly decreases when the Surface Albedo increases. WVC from GOME-2 is, in general, more precise for land than for sea pixels. PMID:26172599

  4. Systematic analysis of interannual and seasonal variations of model-simulated tropospheric NO2 in Asia and comparison with GOME-satellite data

    I. Uno; He, Y.; Ohara, T; Yamaji, K.; J.-I. Kurokawa; M. Katayama; Z. Wang; Noguchi, K.; Hayashida, S; Richter, A; Burrows, J.P.

    2006-01-01

    Systematic analyses of interannual and seasonal variations of tropospheric NO2 vertical column densities (VCDs) based on GOME satellite data and the regional scale chemical transport model (CTM), Community Multi-scale Air Quality (CMAQ), are presented for the atmosphere over eastern Asia between 1996 and June 2003. A newly developed year-by-year emission inventory (REAS) was used in CMAQ. The horizontal distribution of annual averaged GOME NO2 VCDs generally agrees well with the CMAQ results....

  5. Systematic analysis of interannual and seasonal variations of model-simulated tropospheric NO2 in Asia and comparison with GOME-satellite data

    I. Uno; He, Y.; Ohara, T; Yamaji, K.; Kurokawa, J.-I.; M. Katayama; Z. Wang; Noguchi, K.; Hayashida, S; Richter, A; Burrows, J.P.

    2007-01-01

    Systematic analyses of interannual and seasonal variations of tropospheric NO2 vertical column densities (VCDs) based on GOME satellite data and the regional scale chemical transport model (CTM), Community Multi-scale Air Quality (CMAQ), are presented for the atmosphere over eastern Asia between 1996 and June 2003. A newly developed year-by-year emission inventory (REAS) was used in CMAQ. The horizontal distribution of annual averaged GOME NO2 VCDs generally agrees well with...

  6. Estudo farmacognóstico das folhas de Pimenta pseudocaryophyllus (Gomes L.R. Landrum - Myrtaceae Pharmacognostic study about Pimenta pseudocaryophyllus (Gomes L. R. Landrum leaves - Myrtaceae

    Joelma A. M. Paula

    2008-06-01

    Full Text Available O intuito deste trabalho de pesquisa foi obter parâmetros de controle de qualidade para a identificação da matéria-prima vegetal (folha de Pimenta pseudocaryophyllus (Gomes L. R. Landrum - Myrtaceae que ocorre no cerrado brasileiro. Para tanto foram coletadas amostras em Minas Gerais - Brasil e no Distrito Federal - Brasil e as exsicatas foram depositadas no Herbário da UFG n. UFG-27.159 e no Herbário Ezechias Paulo Heringer n. 21.745-0, respectivamente. Parte desse material botânico foi preparada para análises macro e microscópicas. Outra parte foi seca, triturada e usada para a triagem fitoquímica. O estudo mostrou que as folhas de P. pseudocaryophyllus são hipoestomáticas, têm grande quantidade de tricomas unicelulares na superfície abaxial, têm cavidades secretoras contendo compostos lipídicos e as células epidérmicas possuem paredes celulares espessas. Na triagem fitoquímica foram detectados compostos fenólicos, taninos e flavonóides. Os taninos foram dosados por diferentes métodos envolvendo reações colorimétricas e de precipitação com proteínas. Os diferentes resultados verificados chamam a atenção para a necessidade de se especificar o método utilizado juntamente com o limite mínimo de taninos totais estabelecido. Os resultados obtidos configuram-se como importantes parâmetros para o controle de qualidade da matéria-prima vegetal e denotam que a espécie em estudo possui um importante potencial fitoterápico que merece ser investigado em estudos farmacológicos e toxicológicos.The goal of this research was to obtain quality control parameters for the identification of the plant drug of Pimenta pseudocaryophyllus (Gomes L. R. Landrum that occurs in Brazilian savannah. So, two samples were collected, one in Minas Gerais state - Brazil, and the other one in Brasilia city - DF - Brazil, and the vouchers were deposited in the UFG Herbarium code number UFG-27159 and Ezechias Paulo Heringer Herbarium code

  7. Differences between ground Dobson, Brewer and satellite TOMS-8, GOME-WFDOAS total ozone observations at Hradec Kralove, Czech

    Vanicek, K.

    2006-01-01

    This paper presents key results achieved on analysis of relation between high-quality simultaneous Dobson, Brewer ground and TOMS-V8, GOME-WFDOAS satellite total ozone observations for Hradec Kralove, Czech Republic. Statistically significant seasonal differences with maxima up to 4% of monthly averages have been found between Dobson and Brewer measurements in winter/spring months. These differences can influence estimation of ozone trends if combined data series are used after replacement of...

  8. Overview of the O3M SAF GOME-2 operational atmospheric composition and UV radiation data products and data availability

    Hassinen, S.; D. Balis; H. Bauer; Begoin, M.; A. Delcloo; Eleftheratos, K.; S. Gimeno Garcia; Granville, J.; Grossi, M; Hao, N.; Hedelt, P.; Hendrick, F; Hess, M.; Heue, K.-P.; J. Hovila

    2016-01-01

    The three Global Ozone Monitoring Experiment-2 instruments will provide unique and long data sets for atmospheric research and applications. The complete time period will be 2007–2022, including the period of ozone depletion as well as the beginning of ozone layer recovery. Besides ozone chemistry, the GOME-2 (Global Ozone Monitoring Experiment-2) products are important e.g. for air quality studies, climate modelling, policy monitoring and hazard warnings. The heritage for G...

  9. Differences between ground Dobson, Brewer and satellite TOMS-8, GOME-WFDOAS total ozone observations at Hradec Kralove, Czech

    K. Vanicek

    2006-01-01

    Full Text Available This paper presents key results achieved by an analysis of the relation between high-quality simultaneous Dobson, Brewer ground and TOMS-V8, GOME-WFDOAS satellite total ozone observations for Hradec Kralove, Czech Republic. Statistically significant seasonal differences with maxima up to 4% of monthly averages have been found between Dobson and Brewer measurements during the winter/spring months. These differences can influence estimations of ozone trends if combined data series are used after replacing a Dobson instrument by a Brewer spectrophotometer. The differences can be attributed mostly to the influence of temperature on ozone absorption coefficients and to total sulphur dioxide. Similar seasonal differences exist between Dobson, GOME and Brewer, TOMS data sets at Hradec Kralove while Dobson versus TOMS and Brewer versus GOME observations fit well with each other within the instrumental accuracy of spectrophotometers. The above findings are supposed to be relevant to other mid and high latitude stations and they have been confirmed by several independent analyses. The conclusions should be considered by data users because the differences between particular ground and satellite data sets can influence validation of satellite ozone observing systems and analyses of recovery of the ozone layer in mid and high latitudes, among others.

  10. A linear method for the retrieval of sun-induced chlorophyll fluorescence from GOME-2 and SCIAMACHY data

    Köhler, P.; Guanter, L.; Joiner, J.

    2015-06-01

    Global retrievals of near-infrared sun-induced chlorophyll fluorescence (SIF) have been achieved in the last few years by means of a number of space-borne atmospheric spectrometers. Here, we present a new retrieval method for medium spectral resolution instruments such as the Global Ozone Monitoring Experiment-2 (GOME-2) and the SCanning Imaging Absorption SpectroMeter for Atmospheric CHartographY (SCIAMACHY). Building upon the previous work by Guanter et al. (2013) and Joiner et al. (2013), our approach provides a solution for the selection of the number of free parameters. In particular, a backward elimination algorithm is applied to optimize the number of coefficients to fit, which reduces also the retrieval noise and selects the number of state vector elements automatically. A sensitivity analysis with simulated spectra has been utilized to evaluate the performance of our retrieval approach. The method has also been applied to estimate SIF at 740 nm from real spectra from GOME-2 and for the first time, from SCIAMACHY. We find a good correspondence of the absolute SIF values and the spatial patterns from the two sensors, which suggests the robustness of the proposed retrieval method. In addition, we compare our results to existing SIF data sets, examine uncertainties and use our GOME-2 retrievals to show empirically the relatively low sensitivity of the SIF retrieval to cloud contamination.

  11. Validation of GOME-2/MetOp-A total water vapour column using reference radiosonde data from GRUAN network

    M. Antón

    2014-09-01

    Full Text Available The main goal of this article is to validate the total water vapour column (TWVC measured by the Global Ozone Monitoring Experiment-2 (GOME-2 satellite sensor and generated using the GOME Data Processor (GDP retrieval algorithm developed by the German Aerospace Center (DLR. For this purpose, spatially and temporally collocated TWVC data from highly accurate sounding measurements for the period January 2009–May 2014 at six sites are used. These balloon-borne data are provided by GCOS Reference Upper-Air Network (GRUAN. The correlation between GOME-2 and sounding TWVC data is reasonably good (determination coefficient (R2 of 0.89 when all available radiosondes (1400 are employed in the inter-comparison. When cloud-free cases (544 are selected by means of the satellite cloud fraction (CF, the correlation exhibits a remarkable improvement (R2 ~ 0.95. Nevertheless, analyzing the six datasets together, the relative differences between GOME-2 and GRUAN data shows mean values (in absolute term of 19% for all-sky conditions and 14% for cloud-free cases, which evidences a notable bias in the satellite TWVC data against the reference balloon-borne measurements. The satellite-sounding TWVC differences show a strong solar zenith angle (SZA dependence for values above 50° with a stable behaviour for values below this zenith angle. The smallest relative differences found in the inter-comparison (between −5 and +3% are achieved for those cloud-free cases with SZA below 50°. Furthermore, the detailed analysis of the influence of cloud properties (CF, cloud top albedo (CTA and cloud top pressure (CTP on the satellite-sounding differences reveals, as expected, a large effect of clouds in the GOME-2 TWVC data. For instance, the relative differences exhibit a large negative dependence on CTA, varying from +5 to −20% when CTA rises from 0.3 to 0.9. Finally, the satellite-sounding differences also show a negative dependence on the reference TWVC values

  12. Validation of GOME (ERS-2) NO2 vertical column data with ground-based measurements at Issyk-Kul (Kyrgyzstan)

    Ionov, D.; Sinyakov, V.; Semenov, V.

    Starting from 1995 the global monitoring of atmospheric nitrogen dioxide is carried out by the measurements of nadir-viewing GOME spectrometer aboard ERS-2 satellite. Continuous validation of that data by means of comparisons with well-controlled ground-based measurements is important to ensure the quality of GOME data products and improve related retrieval algorithms. At the station of Issyk-Kul (Kyrgyzstan) the ground-based spectroscopic observations of NO2 vertical column have been started since 1983. The station is located on the northern shore of Issyk-Kul lake, 1650 meters above the sea level (42.6 N, 77.0 E). The site is equipped with grating spectrometer for the twilight measurements of zenith-scattered solar radiation in the visible range, and applies the DOAS technique to retrieve NO2 vertical column. It is included in the list of NDSC stations as a complementary one. The present study is focused on validation of GOME NO2 vertical column data, based on 8-year comparison with correlative ground-based measurements at Issyk-Kul station in 1996-2003. Within the investigation, an agreement of both individual and monthly averaged GOME measurements with corresponding twilight ground-based observations is examined. Such agreement is analyzed with respect to different conditions (season, sun elevation), temporal/spatial criteria choice (actual overpass location, correction for diurnal variation) and data processing (GDP version 2.7, 3.0). In addition, NO2 vertical columns were integrated from simultaneous stratospheric profile measurements by NASA HALOE and SAGE-II/III satellite instruments and introduced to explain the differences with ground-based observations. In particular cases, NO2 vertical profiles retrieved from the twilight ground-based measurements at Issuk-Kul were also included into comparison. Overall, summertime GOME NO2 vertical columns were found to be systematicaly lower than ground-based data. This work was supported by International Association

  13. Total ozone retrieval from GOME UV spectral data using the weighting function DOAS approach

    M. Coldewey-Egbers

    2004-08-01

    Full Text Available A new algorithm approach called Weighting Function Differential Optical Absorption Spectroscopy (WFDOAS is presented which has been developed to retrieve total ozone columns from nadir observations of the Global Ozone Monitoring Experiment. By fitting the vertically integrated ozone weighting function rather than ozone cross-section to the sun-normalized radiances, a direct retrieval of vertical column amounts is possible. The new WFDOAS approach takes into account the slant path wavelength modulation that is usually neglected in the standard DOAS approach using single airmass factors. This paper focuses on the algorithm description and error analysis, while in a companion paper by Weber et al. (2004 a detailed validation with groundbased measurements is presented. For the first time several auxiliary quantities directly derived from the GOME spectral range such as cloud-top-height and cloud fraction (O2-A band and effective albedo using the Lambertian Equivalent Reflectivity (LER near 377 nm are used in combination as input to the ozone retrieval. In addition the varying ozone dependent contribution to the Raman correction in scattered light known as Ring effect has been included. Detailed investigations have been performed concerning the influence of the molecular ozone filling-in as part of the Ring effect. The precision of the total ozone retrieval is estimated to be better than 3% for solar zenith angles below 80°.

  14. Total ozone retrieval from GOME UV spectral data using the weighting function DOAS approach

    M. Coldewey-Egbers

    2005-01-01

    Full Text Available A new algorithm approach called Weighting Function Differential Optical Absorption Spectroscopy (WFDOAS is presented which has been developed to retrieve total ozone columns from nadir observations of the Global Ozone Monitoring Experiment. By fitting the vertically integrated ozone weighting function rather than ozone cross-section to the sun-normalized radiances, a direct retrieval of vertical column amounts is possible. The new WFDOAS approach takes into account the slant path wavelength modulation that is usually neglected in the standard DOAS approach using single airmass factors. This paper focuses on the algorithm description and error analysis, while in a companion paper by Weber et al. (2004 a detailed validation with groundbased measurements is presented. For the first time several auxiliary quantities directly derived from the GOME spectral range such as cloud-top-height and cloud fraction (O2-A band and effective albedo using the Lambertian Equivalent Reflectivity (LER near 377nm are used in combination as input to the ozone retrieval. In addition the varying ozone dependent contribution to the Raman correction in scattered light known as Ring effect has been included. The molecular ozone filling-in that is accounted for in the new algorithm has the largest contribution to the improved total ozone results from WFDOAS compared to the operational product. The precision of the total ozone retrieval is estimated to be better than 3% for solar zenith angles below 80°.

  15. Twelve years of global observation of formaldehyde in the troposphere using GOME and SCIAMACHY sensors

    I. De Smedt

    2008-04-01

    Full Text Available This work presents global tropospheric formaldehyde columns retrieved from near-UV radiance measurements performed by the GOME instrument onboard ERS-2 since 1995, and by SCIAMACHY, in operation on ENVISAT since the end of 2002. A special effort has been made to ensure the coherence and quality of the CH2O dataset covering the period 1996–2007. Optimised DOAS settings are proposed in order to reduce the impact of two important sources of error in the derivation of slant columns, namely, the polarisation anomaly affecting the SCIAMACHY spectra around 350 nm, and a major absorption band of the O4 collision complex centred near 360 nm. The air mass factors are determined from scattering weights generated using radiative transfer calculation taking into account the cloud fraction, the cloud height and the ground albedo. Vertical profile shapes of CH2O are provided by the global CTM IMAGES based on an up-to-date representation of emissions, atmospheric transport and photochemistry. A comprehensive error analysis is presented. This includes errors on the slant columns retrieval and errors on the air mass factors which are mainly due to uncertainties in the a priori profile and in the cloud properties. The major features of the retrieved formaldehyde column distribution are discussed and compared with previous CH2O datasets over the major emission regions.

  16. Systematic analysis of interannual and seasonal variations of model-simulated tropospheric NO2 in Asia and comparison with GOME-satellite data

    S. Hayashida

    2006-11-01

    Full Text Available Systematic analyses of interannual and seasonal variations of tropospheric NO2 vertical column densities (VCDs based on GOME satellite data and the regional scale chemical transport model (CTM, Community Multi-scale Air Quality (CMAQ, are presented over eastern Asia between 1996 and June 2003. A newly developed year-by-year emission inventory (REAS was used in CMAQ. The horizontal distribution of annual averaged GOME NO2 VCDs generally agrees well with the CMAQ results. However, CMAQ/REAS results underestimate the GOME retrievals with factors of 2–4 over polluted industrial regions such as Central East China (CEC, a major part of Korea, Hong Kong, and central and western Japan. For the Japan region, GOME and CMAQ NO2 data show good agreement with respect to interannual variation and show no clear increasing trend. For CEC, GOME and CMAQ NO2 data show good agreement and indicate a very rapid increasing trend from 2000. Analyses of the seasonal cycle of NO2 VCDs show that GOME data have systematically larger dips than CMAQ NO2 during February–April and September–November. Sensitivity experiments with fixed emission intensity reveal that the detection of emission trends from satellite in fall or winter have a larger error caused by the variability of meteorology. Examination during summer time and annual averaged NO2 VCDs are robust with respect to variability of meteorology and are therefore more suitable for analyses of emission trends. Analysis of recent trends of annual emissions in China shows that the increasing trends of 1996–1998 and 2000–2002 for GOME and CMAQ/REAS show good agreement, but the rate of increase by GOME is approximately 10–11% yr−1 after 2000; it is slightly steeper than CMAQ/REAS (8–9% yr−1. The greatest difference was apparent between the years 1998 and 2000: CMAQ/REAS only shows a few percentage points of increase, whereas GOME gives a greater than 8% yr−1 increase. The exact reason remains unclear

  17. Systematic analysis of interannual and seasonal variations of model-simulated tropospheric NO2 in Asia and comparison with GOME-satellite data

    I. Uno

    2007-01-01

    Full Text Available Systematic analyses of interannual and seasonal variations of tropospheric NO2 vertical column densities (VCDs based on GOME satellite data and the regional scale chemical transport model (CTM, Community Multi-scale Air Quality (CMAQ, are presented for the atmosphere over eastern Asia between 1996 and June 2003. A newly developed year-by-year emission inventory (REAS was used in CMAQ. The horizontal distribution of annual averaged GOME NO2 VCDs generally agrees well with the CMAQ results. However, CMAQ/REAS results underestimate the GOME retrievals with factors of 2–4 over polluted industrial regions such as Central East China (CEC, a major part of Korea, Hong Kong, and central and western Japan. The most probable reasons for the underestimation typically over the CEC are accuracy of the basic energy statistic data, emission factors, and socio-economic data used for construction of emission inventory. For the Japan region, GOME and CMAQ NO2 data show reasonable agreement with respect to interannual variation and show no clear increasing trend. For CEC, GOME and CMAQ NO2 data indicate a very rapid increasing trend from 2000. Analyses of the seasonal cycle of NO2 VCDs show that GOME data have larger dips than CMAQ NO2 during February–April and September–November. Sensitivity experiments with fixed emission intensity reveal that the detection of emission trends from satellite in fall or winter has a larger error caused by the variability of meteorology. Examination during summer time and annual averaged NO2 VCDs are robust with respect to variability of meteorology and are therefore more suitable for analyses of emission trends. Analysis of recent trends of annual emissions in China shows that the increasing trends of 1996–1998 and 2000–2002 for GOME and CMAQ/REAS show good agreement, but the rate of increase by GOME is approximately 10–11% yr−1 after 2000; it is slightly steeper than CMAQ/REAS (8–9% yr−1. The greatest difference

  18. Estimating the NOx produced by lightning from GOME and NLDN data: a case study in the Gulf of Mexico

    S. Beirle

    2006-01-01

    Full Text Available Nitrogen oxides (NOxNO+NO2 play an important role in tropospheric chemistry, in particular in catalytic ozone production. Lightning provides a natural source of nitrogen oxides, dominating the production in the tropical upper troposphere, with strong impact on tropospheric ozone and the atmosphere's oxidizing capacity. Recent estimates of lightning produced NOx (LNOx are of the order of 5 Tg [N] per year with still high uncertainties in the range of one order of magnitude. The Global Ozone Monitoring Experiment (GOME on board the ESA-satellite ERS-2 allows the retrieval of tropospheric column densities of NO2 on a global scale. Here we present the GOME NO2 measurement directly over a large convective system over the Gulf of Mexico. Simultaneously, cloud-to-ground (CG flashes are counted by the U.S. National Lightning Detection Network (NLDNTM, and extrapolated to include intra-cloud (IC+CG flashes based on a climatological IC:CG ratio derived from NASA's space-based lightning sensors. A series of 14 GOME pixels shows largely enhanced column densities over thick and high clouds, coinciding with strong lightning activity. The enhancements can not be explained by transport of anthropogenic NOx and must be due to fresh production of LNOx. A quantitative analysis, accounting in particular for the visibility of LNOx from satellite, yields a LNOx production of 90 (32-240 moles of NOx, or 1.3 (0.4-3.4 kg [N], per flash. If simply extrapolated, this corresponds to a global LNOx production of 1.7 (0.6-4.7Tg [N]/yr.

  19. Trends in formaldehyde columns over the Amazon rainforest, as observed from space with SCIAMACHY, OMI and GOME-2 spectrometers.

    De Smedt, Isabelle; Stavrakou, Trissevgeni; Lerot, Christophe; Yu, Huan; François, Hendrick; Gielen, Clio; Pinardi, Gaia; Muller, Jean-François; Van Roozendael, Michel

    2015-04-01

    Atmospheric formaldehyde (H2CO) is a central carbonyl compound of tropospheric chemistry. It is produced by the oxidation of a large variety of volatile organic compounds (VOCs), from biogenic, pyrogenic or anthropogenic emission sources. Tropical vegetation, in particular the Amazon forest that represents over half of the planet's remaining rainforests, emit a wide range of highly reactive biogenic volatile organic compounds (BVOCs). Those play a critical role in atmospheric chemistry and climate, by changing the oxidation capacity of the atmosphere and thus the lifetimes of other key trace gases such as CO and CH4, and by producing organic aerosols. Satellite observations of H2CO, bringing information at the global scale and over decades, are essential to trace and understand the nature and the spatio-temporal evolution of VOC emissions. We have been developing algorithms to retrieve formaldehyde columns from satellite nadir UV spectral measurements, and we have processed the full level-1 datasets of GOME/ERS-2, SCIAMACHY/ENVISAT, GOME-2/METOPA&B and OMI/AURA (De Smedt et al., 2008; 2012; 2015). Resulting H2CO products are openly distributed via the TEMIS website (http://h2co.aeronomie.be). In this work, we use the morning and afternoon H2CO columns between 2004 and 2014, respectively composed by the SCIAMACHY and GOME2 A&B datasets, and from the OMI observations, to study the diurnal, seasonal and long-term variations of H2CO over the Amazon rainforest. The highest H2CO columns worldwide are observed, with morning columns markedly higher than early afternoon. Very large variations between the dry and the wet seasons occur each year. Importantly, in some areas of the forest, mainly in the Rondonia Brazilian State, we observe a net decrease of the H2CO columns. We find very high correlation coefficients between the satellite H2CO columns and the reported deforestation fires that have significantly decreased in Rondonia since 2004 [INPE].

  20. Operational Monitoring of GOME-2 and IASI Level 1 Product Processing at EUMETSAT

    Livschitz, Yakov; Munro, Rosemary; Lang, Rüdiger; Fiedler, Lars; Dyer, Richard; Eisinger, Michael

    2010-05-01

    The growing complexity of operational level 1 radiance products from Low Earth Orbiting (LEO) platforms like EUMETSATs Metop series makes near-real-time monitoring of product quality a challenging task. The main challenge is to provide a monitoring system which is flexible and robust enough to identify and to react to anomalies which may be previously unknown to the system, as well as to provide all means and parameters necessary in order to support efficient ad-hoc analysis of the incident. The operational monitoring system developed at EUMETSAT for monitoring of GOME-2 and IASI level 1 data allows to perform near-real-time monitoring of operational products and instrument's health in a robust and flexible fashion. For effective information management, the system is based on a relational database (Oracle). An Extract, Transform, Load (ETL) process transforms products in EUMETSAT Polar System (EPS) format into relational data structures. The identification of commonalities between products and instruments allows for a database structure design in such a way that different data can be analyzed using the same business intelligence functionality. An interactive analysis software implementing modern data mining techniques is also provided for a detailed look into the data. The system is effectively used for day-to-day monitoring, long-term reporting, instrument's degradation analysis as well as for ad-hoc queries in case of an unexpected instrument or processing behaviour. Having data from different sources on a single instrument and even from different instruments, platforms or numerical weather prediction within the same database allows effective cross-comparison and looking for correlated parameters. Automatic alarms raised by checking for deviation of certain parameters, for data losses and other events significantly reduce time, necessary to monitor the processing on a day-to-day basis.

  1. Weekly cycle of NO2 by GOME measurements: A signature of anthropogenic sources

    T. Wagner

    2003-07-01

    Full Text Available Nitrogen oxides (NO+NO2=NOx are important trace gases in the troposphere with impact on human health, atmospheric chemistry and climate. Besides natural sources (lightning, soil emissions and biomass burning, fossil fuel combustion is estimated to be responsible for about 50\\% of the total production of  NOx. Since human activity in industrialized countries largely follows an artificial seven-day cycle, fossil fuel combustion is expected to  be reduced during weekends. This "weekend effect" is well known from local, ground based measurements, but has never been analysed on a global scale before. The Global Ozone Monitoring Experiment (GOME on board the ESA-satellite ERS-2 allows measurements of  NO2 column densities. Applying sophisticated algorithms, vertical column densities (VCD of tropospheric NO2 can be determined. We demonstrate the statistical analysis of weekly cycles of tropospheric NO2 VCDs for different regions of the world. In the cycles of the industrialized regions and cities in the US, Europe and Japan a clear Sunday minimum of tropospheric NO2 VCD can be seen. Sunday NO2 VCDs are about 25–50% lower than working day levels. Metropolitan areas with other religious and cultural backgrounds (Jerusalem, Mecca show different weekly patterns corresponding to different days of rest. In China, no weekly pattern can be found. The presence of a weekly cycle in the measured tropospheric NO2 VCD allows the identification of anthropogenic sources. In addition, the fraction of emissions subjected to a weekly cycle (mainly transport, power generation with respect to a constant background (all kind of natural sources, biomass burning, heavy industry can be estimated. Furthermore, we estimated the lifetime of tropospheric NO2 by analysing the mean weekly cycle over Germany in detail, obtaining a value of about 12 h.

  2. Macrophytobenthic flora of the Abrolhos Archipelago and the Sebastião Gomes Reef, Brazil

    Torrano-Silva, Beatriz N.; Oliveira, Eurico C.

    2013-11-01

    The Abrolhos Bank, located on the coast of Bahia, Brazil, harbors the largest coral reef system in the South Atlantic. This area has attracted the attention of biologists because of its peculiar mushroom-shaped structures, locally known as "chapeirões", and endemic species of corals and other organisms. The macrophytobenthos compartment plays an important ecological role in the functioning of the bank, and some reports on the presence of seaweeds and seagrasses have been published; however, the data are fragmentary, and a more detailed survey of the macrophytobenthos compartment is lacking. Here we consolidate the information available and add new data obtained from two expeditions focused on seaweed and seagrass diversity from two sectors of the bank: the islands of the Abrolhos archipelago (AA) and the Sebastião Gomes Reef (SG). These sites were selected for their contrasting characteristics. Specifically, SG (15 km off the mouth of the Caravelas River) is subjected to a broader range of anthropogenic impacts and to input of terrigenous sediments, while the AA (54 km offshore) is surrounded by calcareous biogenic sediments, has clearer water and is less affected by human activities. Macrophytobenthic species richness on both reference areas is larger than previously thought. Considering previous records, there are 164 species of macrophytes in AA and 111 species in SG, of which 59 and 74 species are first records for each respective location. The higher species richness at the AA may result from a higher habitat complexity and lower turbidity, but a potential negative effect of enhanced human impacts at SG cannot be ruled out. Considering that macroalgae are relevant components of the benthic community, as producers and structurer organisms, the data presented herein provide a reliable baseline for future environmental studies, and thus may contribute to improve management policies within the unique ecosystem of Abrolhos.

  3. Operational surface UV radiation product from GOME-2 and AVHRR/3 data

    Kujanpää, J.; Kalakoski, N.

    2015-10-01

    The surface ultraviolet (UV) radiation product, version 1.20, generated operationally in the framework of the Satellite Application Facility on Ozone and Atmospheric Chemistry Monitoring (O3M SAF) of the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) is described. The product is based on the total ozone column derived from the measurements of the second Global Ozone Monitoring Experiment (GOME-2) instrument aboard EUMETSAT's polar orbiting meteorological operational (Metop) satellites. Cloud cover is taken into account by retrieving cloud optical depth from the channel 1 reflectance of the third Advanced Very High-Resolution Radiometer (AVHRR/3) instrument aboard both Metop in the morning orbit and Polar Orbiting Environmental Satellites (POES) of the National Oceanic and Atmospheric Administration (NOAA) in the afternoon orbit. In addition, more overpasses are used at high latitudes where the swaths of consecutive orbits overlap. The input satellite data are received from EUMETSAT's Multicast Distribution System (EUMETCast). The surface UV product includes daily maximum dose rates and integrated daily doses with different biological weighting functions, integrated ultraviolet B (UVB) and ultraviolet A (UVA) radiation, solar noon UV index and daily maximum photolysis frequencies of ozone and nitrogen dioxide at the surface level. The quantities are computed in a 0.5°×0.5° regular latitude-longitude grid and stored as daily files in the hierarchical data format (HDF5) within 2 weeks from sensing. The product files are archived in the O3M SAF distributed archive and can be ordered via the EUMETSAT Data Centre.

  4. Operational surface UV radiation product from GOME-2 and AVHRR/3 data

    J. Kujanpää

    2015-10-01

    Full Text Available The surface ultraviolet (UV radiation product, version 1.20, generated operationally in the framework of the Satellite Application Facility on Ozone and Atmospheric Chemistry Monitoring (O3M SAF of the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT is described. The product is based on the total ozone column derived from the measurements of the second Global Ozone Monitoring Experiment (GOME-2 instrument aboard EUMETSAT's polar orbiting meteorological operational (Metop satellites. Cloud cover is taken into account by retrieving cloud optical depth from the channel 1 reflectance of the third Advanced Very High-Resolution Radiometer (AVHRR/3 instrument aboard both Metop in the morning orbit and Polar Orbiting Environmental Satellites (POES of the National Oceanic and Atmospheric Administration (NOAA in the afternoon orbit. In addition, more overpasses are used at high latitudes where the swaths of consecutive orbits overlap. The input satellite data are received from EUMETSAT's Multicast Distribution System (EUMETCast. The surface UV product includes daily maximum dose rates and integrated daily doses with different biological weighting functions, integrated ultraviolet B (UVB and ultraviolet A (UVA radiation, solar noon UV index and daily maximum photolysis frequencies of ozone and nitrogen dioxide at the surface level. The quantities are computed in a 0.5°×0.5° regular latitude–longitude grid and stored as daily files in the hierarchical data format (HDF5 within 2 weeks from sensing. The product files are archived in the O3M SAF distributed archive and can be ordered via the EUMETSAT Data Centre.

  5. Weekly cycle of NO2 by GOME measurements: a signature of anthropogenic sources

    S. Beirle

    2003-01-01

    Full Text Available Nitrogen oxides (NO+NO2=NOx and reservoir species are important trace gases in the troposphere with impact on human health, atmospheric chemistry and climate. Besides natural sources (lightning, soil emissions and biomass burning, fossil fuel combustion is estimated to be responsible for about 50% of the total production of NOx. Since human activity in industrialized countries largely follows a seven-day cycle, fossil fuel combustion is expected to be reduced during weekends. This 'weekend effect' is well known from local, ground based measurements, but has never been analysed on a global scale before. The Global Ozone Monitoring Experiment (GOME on board the ESA-satellite ERS-2 allows measurements of NO2 column densities. By estimating and subtracting the stratospheric column, and considering radiative transfer, vertical column densities (VCD of tropospheric NO2 can be determined (e.g. Leue et al., 2001. We demonstrate the statistical analysis of weekly cycles of tropospheric NO2 VCDs for different regions of the world. In the cycles of the industrialized regions and cities in the US, Europe and Japan a clear Sunday minimum of tropospheric NO2 VCD can be seen. Sunday NO2 VCDs are about 25-50% lower than working day levels. Metropolitan areas with other religious and cultural backgrounds (Jerusalem, Mecca show different weekly patterns corresponding to different days of rest. In China, no weekly pattern can be found. The presence of a weekly cycle in the measured tropospheric NO2 VCD may help to identify the different anthropogenic source categories. Furthermore, we estimated the lifetime of tropospheric NO2 by analysing the mean weekly cycle exemplarily over Germany, obtaining a value of about 6 h in summer and 18-24 h in winter.

  6. Evaluation of long-term tropospheric NO2 data obtained by GOME over East Asia in 1996-2002

    Irie, H.; K. Sudo; Akimoto, H.; A. Richter; Burrows, J.-P.; Wagner, T.; M. Wenig; Beirle, S.; Kondo, Y.; Sinyakov, V.-P.; Goutail, Florence

    2005-01-01

    Long-term tropospheric nitrogen dioxide (NO2) column data obtained by the Global Ozone Monitoring Experiment (GOME) (G-NO2) are evaluated to confirm the trends found in tropospheric NO2 abundances over East Asia between 1996 and 2002. For three locations in Central and East Asia, the G-NO2 values are compared with tropospheric columns estimated from coincident observations of total NO2 by ground-based UV/visible spectrometers and stratospheric NO2 by satellite solar occultation sensors (E-NO2...

  7. Overview of the O3M-SAF validation facility for operational GOME-2 NO2 column data

    Pinardi, Gaia; Lambert, Jean-Christopher; Granville, Jos; van Roozendael, Michel; Delcloo, Andy; Debacker, Hugo; Valks, Pieter; Hao, Nan

    In the framework of EUMETSAT's Satellite Application Facility on Ozone and Atmospheric Chemistry Monitoring (O3M-SAF,) nitrogen dioxide (NO2) total column and tropospheric column data are generated operationally from GOME-2 measurements in near-real-time (within 2:30 hours after sensing). NO2 column data are retrieved from the Earth radiance and solar irradiance spectra by a chain of several modules (currently, the level-0-to-1 processor v4.0 and the level-1-to-2 DOAS retrieval processor GDP v4.3). These intermediate modules calculates the parameters needed to derive the final column data: the slant column density along the optical path, the fractional cover and top pressure of clouds affecting the measurement scene, the geometrical enhancement factor (AMF, needed to convert slant into vertical columns), and the NO2 stratospheric reference to be subtracted from the total column to obtain the tropospheric column. In order to validate the final product (the total and tropospheric NO2 columns) in the best way, and due to the complexity of the GOME-2 retrieval chain and the existing issues related to the set-up of a validation strategy in an operational environment, an end-to-end validation ap-proach has been developed, as recommended by Reference Protocols and Guidelines. To ensure meaningful and continuous quality assessment of GOME-2 NO2 data products, the end-to-end validation approach performs the verification and validation of critical individual components of the level-1-to-2 retrieval chain. Particular interest is given to recurring validation issues, such as the particular way remote sensing samples and smoothes the significant variability of atmospheric NO2, the diurnal cycle of NO2, the poor availability of correlative measure-ments (especially for tropospheric column), as well as the current lack of homogenisation of the validation methods. The end-to-end validation process of GOME-2 NO2 data is based on a set of correlative obser-vations performed by

  8. Improved retrieval of global tropospheric formaldehyde columns from GOME-2/MetOp-A addressing noise reduction and instrumental degradation issues

    I. De Smedt; Van Roozendael, M.; T. Stavrakou; F. Mueller, J.; C. Lerot; N. Theys; Valks, Pieter; Hao, Nan; Van Der A, R.

    2012-01-01

    We present a new dataset of formaldehyde vertical columns retrieved from observations of GOME-2 on board the EUMETSAT MetOp-A platform between 2007 and 2011. The new retrieval scheme, which has been optimised for GOME-2, includes a two-step fitting procedure that strongly reduces the impact of spectral interferences between H2CO and BrO, and a modified DOAS approach that better handles ozone absorption effects at moderately low sun elevations. Owing to these new features, the noise in the H2C...

  9. Improved retrieval of global tropospheric formaldehyde columns from GOME-2/MetOp-A addressing noise reduction and instrumental degradation issues

    I. De Smedt; Van Roozendael, M.; T. Stavrakou; J.-F. Müller; C. Lerot; N. Theys; Valks, P.; Hao, N.; R. van der A

    2012-01-01

    We present a new data set of formaldehyde vertical columns retrieved from observations of GOME-2 onboard of the EUMETSAT MetOp-A platform between 2007 and 2011. The new retrieval scheme, which has been optimised for GOME-2, includes a two-step fitting procedure that strongly reduces the impact of spectral interferences between H2CO and BrO, and a modified DOAS approach that better handles ozone absorption effects at moderately low sun elevations. Owing to these new feat...

  10. First quantitative bias estimates for tropospheric NO2 columns retrieved from SCIAMACHY, OMI, and GOME-2 using a common standard

    X. Pan

    2012-06-01

    Full Text Available For the intercomparison of tropospheric nitrogen dioxide NO2 vertical column density (VCD data from three different satellite sensors (SCIAMACHY, OMI, and GOME-2, we use a common standard to quantitatively evaluate the biases for the respective data sets. As the standard, a regression analysis using a single set of collocated ground-based Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS observations at several sites in Japan and China in 2006–2011 is adopted. Examination of various spatial coincidence criteria indicates that the slope of the regression line can be influenced by the spatial distribution of NO2 over the area considered. While the slope varies systematically with the distance between the MAX-DOAS and satellite observation points around Tokyo in Japan, such a systematic dependence is not clearly seen and correlation coefficients are generally higher in comparisons at sites in China. On the basis of these results, we focus mainly on comparisons over China and best estimate the biases in SCIAMACHY, OMI, and GOME-2 data (TM4NO2A and DOMINO version 2 products against the MAX-DOAS observations to be −5±14 %, −10±14 %, and +1±14 %, respectively, which are all small and insignificant. We suggest that these small biases now allow analyses combining these satellite data for air quality studies that are more systematic and quantitative than previously possible.

  11. Round-robin evaluation of nadir ozone profile retrievals: methodology and application to MetOp-A GOME-2

    A. Keppens

    2014-11-01

    Full Text Available A methodology for the round-robin evaluation and geophysical validation of ozone profile data retrieved from nadir UV backscatter satellite measurements is detailed and discussed, consisting of dataset content studies, information content studies, co-location studies, and comparisons with reference measurements. Within ESA's Climate Change Initiative on ozone (Ozone_cci project, the proposed round-robin procedure is applied to two nadir ozone profile datasets retrieved at KNMI and RAL, using their respective OPERA v1.26 and RAL v2.1 optimal estimation algorithms, from MetOp-A GOME-2 measurements taken in 2008. The ground-based comparisons use ozonesonde and lidar profiles as reference data, acquired by the Network for the Detection of Atmospheric Composition Change (NDACC, Southern Hemisphere Additional Ozonesonde programme (SHADOZ, and other stations of WMO's Global Atmosphere Watch. This direct illustration highlights practical issues that inevitably emerge from discrepancies in e.g. profile representation and vertical smoothing, for which different recipes are investigated and discussed. Several approaches for information content quantification, vertical resolution estimation, and reference profile resampling are compared and applied as well. The paper concludes with compliance estimates of the two GOME-2 ozone profile datasets with user requirements from GCOS and from climate modellers.

  12. Temporal and spectral variation of desert dust and biomass burning aerosol scenes from 1995–2000 using GOME

    I. Aben

    2006-02-01

    Full Text Available Global Ozone Monitoring Experiment (GOME Absorbing Aerosol Index (AAI and AAI-related residue data were used to investigate areas with UV-absorbing aerosols. Time series of regionally averaged residues show the seasonal variation and trends of aerosols and clouds in climatologically important parts of the globe. GOME spectra were used to study scenes containing specific types of aerosols. AAI data are specifically sensitive to biomass burning aerosols (BBA and desert dust aerosols (DDA. Areas where these aerosols are regularly found were analysed to find spectral fingerprints in the ultraviolet (UV, visible and near-infrared (near-IR, to establish an aerosol type classification of BBA and DDA. Spectral residues are different for BBA and DDA, but over deserts the surface albedo is dominant beyond the UV and spectral residues cannot be used over land. Over oceans, about half of the BBA scenes show a very high reflectance that is never observed for DDA scenes. However, in the case of low reflectance scenes BBA and DDA cannot be distinguished. This is in part due to the microphysical and optical properties of biomass burning aerosols, which are highly variable in time, making it difficult to specify them spectrally as one type. Because of their high hygroscopicity BBA are often found in the presence of clouds, which disturb the spectrum of the scenes. Desert dust aerosols are much less hygroscopic and behave spectrally more uniformly.

  13. How consistent are top-down hydrocarbon emissions based on formaldehyde observations from GOME-2 and OMI?

    T. Stavrakou

    2015-04-01

    Full Text Available The vertical columns of formaldehyde (HCHO retrieved from two satellite instruments, the Global Ozone Monitoring Instrument-2 (GOME-2 on Metop-A and the Ozone Monitoring Instrument (OMI on Aura, are used to constrain global emissions of HCHO precursors from open fires, vegetation and human activities in the year 2010. To this end, the emissions are varied and optimized using the adjoint model technique in the IMAGESv2 global CTM (chemistry-transport model on a monthly basis and at the model resolution. Given the different local overpass times of GOME-2 (09:30 LT and OMI (13:30 LT, the simulated diurnal cycle of HCHO columns is investigated and evaluated against ground-based optical measurements at 7 sites in Europe, China and Africa. The modelled diurnal cycle exhibits large variability, reflecting competition between photochemistry and emission variations, with noon or early afternoon maxima at remote locations (oceans and in regions dominated by anthropogenic emissions, late afternoon or evening maxima over fire scenes, and midday minima in isoprene-rich regions. The agreement between simulated and ground-based columns is found to be generally better in summer (with a clear afternoon maximum at mid-latitude sites than in winter, and the annually averaged ratio of afternoon to morning columns is slightly higher in the model (1.126 than in the ground-based measurements (1.043. The anthropogenic VOC (volatile organic compound sources are found to be weakly constrained by the inversions on the global scale, mainly owing to their generally minor contribution to the HCHO columns, except over strongly polluted regions, like China. The OMI-based inversion yields total flux estimates over China close to the bottom-up inventory (24.6 vs. 25.5 in the a priori with, however, pronounced increases in the Northeast China and reductions in the south. Lower fluxes are estimated based on GOME-2 HCHO columns (20.6 TgVOC, in particular over the Northeast, likely

  14. Operational surface UV radiation product from GOME-2 and AVHRR/3 data

    J. Kujanpää

    2015-05-01

    Full Text Available The surface ultraviolet (UV radiation product, version 1.20, generated operationally in the framework of the Satellite Application Facility on Ozone and Atmospheric Chemistry Monitoring (O3M SAF of the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT is described. The product is based on the total ozone column derived from the measurements of the second Global Ozone Monitoring Experiment (GOME-2 instrument aboard EUMETSAT's polar orbiting meteorological operational (Metop satellites. The input total ozone product is generated by the German Aerospace Center (DLR also within the O3M SAF framework. Polar orbiting satellites provide global coverage but infrequent sampling of the diurnal cloud cover. The diurnal variation of the surface UV radiation is extremely strong due to modulation by solar elevation and rapidly changing cloud cover. At the minimum, one sample of the cloud cover in the morning and another in the afternoon are needed to derive daily maximum and daily integrated surface UV radiation quantities. This is achieved by retrieving cloud optical depth from the channel 1 reflectance of the third Advanced Very High Resolution Radiometer (AVHRR/3 instrument aboard both Metop in the morning orbit (daytime descending node around 09:30 LT and Polar Orbiting Environmental Satellites (POES of the National Oceanic and Atmospheric Administration (NOAA in the afternoon orbit (daytime ascending node around 14:30 LT. In addition, more overpasses are used at high latitudes where the swaths of consecutive orbits overlap. The input satellite data are received from EUMETSAT's Multicast Distribution System (EUMETCast using commercial telecommunication satellites for broadcasting the data to the user community. The surface UV product includes daily maximum dose rates and integrated daily doses with different biological weighting functions, integrated UVB and UVA radiation, solar noon UV Index and daily maximum photolysis

  15. Biografia como história social: o clã Ferreira Gomes e os mundos da escravização no Atlântico Sul

    Roquinaldo Ferreira

    2013-12-01

    Full Text Available Este artigo analisa as conexões econômicas e sociais engendradas pelo tráfico de escravos entre Angola e Brasil, assim como o abolicionismo português na primeira metade do século XIX. Neste sentido, o artigo usa como ponto de partida a trajetória pessoal de José Ferreira Gomes, um homem negro, nascido em Benguela, cuja mãe, Florinda José Gaspar, era filha de um chefe africano da Catumbela e cujo pai, Francisco Ferreira Gomes, foi um homem negro nascido no Brasil que tinha sido um dos traficantes de escravos mais ativos em Benguela. Tendo como base a biografia de Gomes Júnior, o artigo discute os laços sociais e culturais que os traficantes de escravos angolanos mantinham com o Brasil e com as populações africanas, a transição do tráfico de escravos para o comércio lícito, e as mudanças na políticas portuguesas em relação ao tráfico de escravos na década de 1840. Para entender o recrudescimento do colonialismo em Angola, o artigo examina acusações de que membros da família Ferreira Gomes teriam participado de sedições raciais e anti-coloniais contra os portugueses.

  16. Temperature dependent ozone absorption cross section spectra measured with the GOME-2 FM3 spectrometer and first application in satellite retrievals

    W. Chehade

    2012-10-01

    Full Text Available The Global Ozone Monitoring Experiment (GOME-2 Flight Model (FM absorption cross section spectra of ozone were measured under representative atmospheric conditions in the laboratory setup at temperatures between 203 K and 293 K in the wavelength range of 230–790 nm at a medium spectral resolution of 0.24 to 0.54 nm. Since the exact ozone amounts were unknown in the gas flow system used, the measured ozone cross sections were required to be scaled to absolute cross section units using published literature data. The Hartley, Huggins and Chappuis bands were recorded simultaneously and their temperature dependence is in good agreement with previous studies (strong temperature effect in the Huggins band and weak in the Hartley and Chappuis bands. The overall agreement of the GOME-2 FM cross sections with the literature data is well within 3%. The total ozone column retrieved from the GOME-2/MetOp-A satellite using the new cross section data is within 1% compared to the ozone amounts retrieved routinely from GOME-2.

  17. Temperature Dependent Absorption Cross-Sectionsof O3 and NO2 in the 240 - 790 nm range determined by using the GOME-2 Satellite Spectrometers for use in Remote Sensing Applications

    Gür, Bilgehan

    2006-01-01

    Absorption spectra of O3 and NO2 have been measured in three independent campaigns using the three highly stabilized and accurately characterized GOME-2 satellite spectrometers,flight models FM2, FM2-1, and FM3.GOME-2 (Global Ozone MonitoringExperiment) is an enhanced follow-up project of GOME, which was launched on ESA's second European Remote Sensing Satellite (ERS-2) in 1995.A new generation of satellites for earth observation will be available with the MetOp series, starting most likely i...

  18. How consistent are top-down hydrocarbon emissions based on formaldehyde observations from GOME-2 and OMI?

    Stavrakou, T. [Belgium Inst. for Space Aeronomy, Brussels (Belgium); Muller, J. F. [Belgium Inst. for Space Aeronomy, Brussels (Belgium); Bauwens, M. [Belgium Inst. for Space Aeronomy, Brussels (Belgium); De Smedt, I. [Belgium Inst. for Space Aeronomy, Brussels (Belgium); Van Roozendael, M. [Belgium Inst. for Space Aeronomy, Brussels (Belgium); De Maziere, M. [Belgium Inst. for Space Aeronomy, Brussels (Belgium); Vigouroux, C. [Belgium Inst. for Space Aeronomy, Brussels (Belgium); Hendrick, F. [Belgium Inst. for Space Aeronomy, Brussels (Belgium); George, M. [UPMC Univ., Paris (France); Clerbaux, C. [UPMC Univ., Paris (France); Free University of Brussels (Germany); Coheur, P-F [Free University of Brussels (Germany); Guenther, Alex B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-10-26

    The vertical columns of formaldehyde (HCHO) retrieved from two satellite instruments, the Global Ozone Monitoring Instrument-2 (GOME-2) on Metop-A and the Ozone Monitoring Instrument (OMI) on Aura, are used to constrain global emissions of HCHO precursors from open fires, vegetation and human activities in the year 2010. To this end, the emissions are varied and optimized using the ad-joint model technique in the IMAGESv2 global CTM (chem-ical transport model) on a monthly basis and at the model res-olution. Given the different local overpass times of GOME- 2 (09:30 LT) and OMI (13:30 LT), the simulated diurnal cy-cle of HCHO columns is investigated and evaluated against ground-based optical measurements at seven sites in Europe, China and Africa. The modeled diurnal cycle exhibits large variability, reflecting competition between photochemistry and emission variations, with noon or early afternoon max-ima at remote locations (oceans) and in regions dominated by anthropogenic emissions, late afternoon or evening max-ima over fire scenes, and midday minima in isoprene-rich re-gions. The agreement between simulated and ground-based columns is generally better in summer (with a clear after-noon maximum at mid-latitude sites) than in winter, and the annually averaged ratio of afternoon to morning columns is slightly higher in the model (1.126) than in the ground-based measurements (1.043).The anthropogenic VOC (volatile organic compound) sources are found to be weakly constrained by the inversions on the global scale, mainly owing to their generally minor contribution to the HCHO columns, except over strongly pol-luted regions, like China. The OMI-based inversion yields total flux estimates over China close to the bottom-up inven-tory (24.6 vs. 25.5 TgVOC yr-1 in the a priori) with, how-ever, pronounced increases in the northeast of China and re-ductions in the south. Lower fluxes are estimated based on GOME-2 HCHO columns (20.6 TgVOC yr-1), in

  19. Diurnal, seasonal and long-term variations of global formaldehyde columns inferred from combined OMI and GOME-2 observations

    De Smedt, I.; Stavrakou, T.; Hendrick, F.; Danckaert, T.; Vlemmix, T.; Pinardi, G.; Theys, N.; Lerot, C.; Gielen, C.; Vigouroux, C.; Hermans, C.; Fayt, C.; Veefkind, P.; Müller, J.-F.; Van Roozendael, M.

    2015-11-01

    We present the new version (v14) of the BIRA-IASB algorithm for the retrieval of formaldehyde (H2CO) columns from spaceborne UV-visible sensors. Applied to OMI measurements from Aura and to GOME-2 measurements from MetOp-A and MetOp-B, this algorithm is used to produce global distributions of H2CO representative of mid-morning and early afternoon conditions. Its main features include (1) a new iterative DOAS scheme involving three fitting intervals to better account for the O2-O2 absorption, (2) the use of earthshine radiances averaged in the equatorial Pacific as reference spectra, and (3) a destriping correction and background normalisation resolved in the across-swath position. For the air mass factor calculation, a priori vertical profiles calculated by the IMAGES chemistry transport model at 09:30 and 13:30 LT are used. Although the resulting GOME-2 and OMI H2CO vertical columns are found to be highly correlated, some systematic differences are observed. Afternoon columns are generally larger than morning ones, especially in mid-latitude regions. In contrast, over tropical rainforests, morning H2CO columns significantly exceed those observed in the afternoon. These differences are discussed in terms of the H2CO column variation between mid-morning and early afternoon, using ground-based MAX-DOAS measurements available from seven stations in Europe, China and Africa. Validation results confirm the capacity of the combined satellite measurements to resolve diurnal variations in H2CO columns. Furthermore, vertical profiles derived from MAX-DOAS measurements in the Beijing area and in Bujumbura are used for a more detailed validation exercise. In both regions, we find an agreement better than 15 % when MAX-DOAS profiles are used as a priori for the satellite retrievals. Finally, regional trends in H2CO columns are estimated for the 2004-2014 period using SCIAMACHY and GOME-2 data for morning conditions, and OMI for early afternoon conditions. Consistent features

  20. Diurnal, seasonal and long-term variations of global formaldehyde columns inferred from combined OMI and GOME-2 observations

    I. De Smedt

    2015-04-01

    Full Text Available We present the new version (v14 of the BIRA-IASB algorithm for the retrieval of formaldehyde (H2CO columns from spaceborne UV-Visible sensors. Applied to OMI measurements from Aura and to GOME-2 measurements from MetOp-A and B, this algorithm is used to produce global distributions of H2CO representative of mid-morning and early afternoon conditions. Its main features include (1 a new iterative DOAS scheme involving three fitting intervals to better account for the O2-O2 absorption, (2 the use of earthshine radiances averaged in the equatorial Pacific as reference spectra, (3 a destriping correction and background normalisation resolved in the along-swath position. For the air mass factor calculation, a priori vertical profiles calculated by the IMAGES chemistry transport model at 9.30 a.m. and 13.30 p.m. are used. Although the resulting GOME-2 and OMI H2CO vertical columns are found to be highly correlated, some systematic differences are observed. Afternoon columns are generally larger than morning ones, especially in mid-latitude regions. In contrast, over tropical rainforests, morning H2CO columns significantly exceed those observed in the afternoon. These differences are discussed in terms of the H2CO column variation between mid-morning and early afternoon, using ground-based MAX-DOAS measurements available from seven stations in Europe, China and Africa. Validation results confirm the capacity of the combined satellite measurements to resolve diurnal variations in H2CO columns. Furthermore, vertical profiles derived from MAX-DOAS measurements in the Beijing area and in Bujumbura are used for a more detailed validation exercise. In both regions, we find an agreement better than 15% when MAX-DOAS profiles are used as a priori for the satellite retrievals. Finally regional trends in H2CO columns are estimated for the 2004–2014 period using SCIAMACHY and GOME-2 data for morning conditions, and OMI for early afternoon conditions. Consistent

  1. The direct fitting approach for total ozone column retrievals: a sensitivity study on GOME-2/MetOp-A measurements

    Wassmann, A.; Borsdorff, T.; aan de Brugh, J. M. J.; Hasekamp, O. P.; Aben, I.; Landgraf, J.

    2015-10-01

    We present a sensitivity study of the direct fitting approach to retrieve total ozone columns from the clear sky Global Ozone Monitoring Experiment 2/MetOp-A (GOME-2/MetOp-A) measurements between 325 and 335 nm in the period 2007-2010. The direct fitting of the measurement is based on adjusting the scaling of a reference ozone profile and requires accurate simulation of GOME-2 radiances. In this context, we study the effect of three aspects that introduce forward model errors if not addressed appropriately: (1) the use of a clear sky model atmosphere in the radiative transfer demanding cloud filtering, (2) different approximations of Earth's sphericity to address the influence of the solar zenith angle, and (3) the need of polarization in radiative transfer modeling. We conclude that cloud filtering using the operational GOME-2 FRESCO (Fast Retrieval Scheme for Clouds from the Oxygen A band) cloud product, which is part of level 1B data, and the use of pseudo-spherical scalar radiative transfer is fully sufficient for the purpose of this retrieval. A validation with ground-based measurements at 36 stations confirms this showing a global mean bias of -0.1 % with a standard deviation (SD) of 2.7 %. The regularization effect inherent to the profile scaling approach is thoroughly characterized by the total column averaging kernel for each individual retrieval. It characterizes the effect of the particular choice of the ozone profile to be scaled by the inversion and is part of the retrieval product. Two different interpretations of the data product are possible: first, regarding the retrieval product as an estimate of the true column, a direct comparison of the retrieved column with total ozone columns from ground-based measurements can be done. This requires accurate a priori knowledge of the reference ozone profile and the column averaging kernel is not needed. Alternatively, the retrieval product can be interpreted as an effective column defined by the total column

  2. The GOME-2 instrument on the Metop series of satellites: instrument design, calibration, and level 1 data processing - an overview

    Munro, Rosemary; Lang, Rüdiger; Klaes, Dieter; Poli, Gabriele; Retscher, Christian; Lindstrot, Rasmus; Huckle, Roger; Lacan, Antoine; Grzegorski, Michael; Holdak, Andriy; Kokhanovsky, Alexander; Livschitz, Jakob; Eisinger, Michael

    2016-03-01

    The Global Ozone Monitoring Experiment-2 (GOME-2) flies on the Metop series of satellites, the space component of the EUMETSAT Polar System. In this paper we will provide an overview of the instrument design, the on-ground calibration and characterization activities, in-flight calibration, and level 0 to 1 data processing. The current status of the level 1 data is presented and points of specific relevance to users are highlighted. Long-term level 1 data consistency is also discussed and plans for future work are outlined. The information contained in this paper summarizes a large number of technical reports and related documents containing information that is not currently available in the published literature. These reports and documents are however made available on the EUMETSAT web pages and readers requiring more details than can be provided in this overview paper will find appropriate references at relevant points in the text.

  3. Implementation of a radiation protection program, in radioisotope handling laboratories, of Instituto de Biologia Roberto Alcantara Gomes

    The present work portrays the current situation of the laboratories of the Institute of Biology Roberto Alcantara Gomes (IBRAG), that manipulate radioactive sources and the importance of the implementation of a program in radiological protection. To evaluate such situation, visits they were accomplished, questionnaires destined to the coordinators of the laboratories and the users. And laboratories were characterized. The results pointed some irregularities on radiation protection and demonstrated the real need to implement a radiological program that include program training and recommends a Guide for all technicians. The presented results demonstrate the most of the users do not know about the norms of radiological protection of Comissao Nacional de Energia Nuclear (CNEN). And the most of the laboratories do not execute the procedures established from CNEN. Than it is necessary that the laboratories of IBRAG reorganize its practices in radiological protection, invests in equipment, technical training and radioprotection structure. (author)

  4. Improved retrieval of global tropospheric formaldehyde columns from GOME-2/MetOp-A addressing noise reduction and instrumental degradation issues

    I. De Smedt

    2012-08-01

    Full Text Available We present a new data set of formaldehyde vertical columns retrieved from observations of GOME-2 onboard of the EUMETSAT MetOp-A platform between 2007 and 2011. The new retrieval scheme, which has been optimised for GOME-2, includes a two-step fitting procedure that strongly reduces the impact of spectral interferences between H2CO and BrO, and a modified DOAS approach that better handles ozone absorption effects at moderately low sun elevations. Owing to these new features, the noise in the H2CO slant columns is reduced by up to 40% in comparison to baseline retrieval settings used operationally. Also, the previously reported underestimation of the H2CO columns in tropical and mid-latitudes regions has been largely eliminated, improving the agreement with coincident SCIAMACHY observations. To compensate for the drift of the GOME-2 slit function and to mitigate the instrumental degradation effects on H2CO retrievals, an asymmetric Gaussian line shape is fitted during the irradiance calibration. Additionally, external parameters used in the tropospheric air mass factor computation (surface reflectances, cloud parameters and a priori profile shapes of H2CO have been updated using most recent data bases. Similar updates were also applied to the historical data sets of GOME and SCIAMACHY leading to the generation of a consistent multi-mission H2CO data record covering the time period from 1997 until 2011. Comparing the resulting time series of monthly averaged H2CO vertical columns in 12 large regions worldwide, the correlation coefficient between SCIAMACHY and GOME-2 columns is generally higher than 0.8 in the overlap period, and linear regression slopes differ by less than 10% from unity in most of the regions. In comparison to SCIAMACHY, the largely improved spatial sampling of GOME-2 allows for a better characterisation of formaldehyde distribution at the regional scale

  5. Improved retrieval of global tropospheric formaldehyde columns from GOME-2/MetOp-A addressing noise reduction and instrumental degradation issues

    I. De Smedt

    2012-11-01

    Full Text Available We present a new dataset of formaldehyde vertical columns retrieved from observations of GOME-2 on board the EUMETSAT MetOp-A platform between 2007 and 2011. The new retrieval scheme, which has been optimised for GOME-2, includes a two-step fitting procedure that strongly reduces the impact of spectral interferences between H2CO and BrO, and a modified DOAS approach that better handles ozone absorption effects at moderately low sun elevations. Owing to these new features, the noise in the H2CO slant columns is reduced by up to 40% in comparison to baseline retrieval settings used operationally. Also, the previously reported underestimation of the H2CO columns in tropical and mid-latitude regions has been largely eliminated, improving the agreement with coincident SCIAMACHY observations. To compensate for the drift of the GOME-2 slit function and to mitigate the instrumental degradation effects on H2CO retrievals, an asymmetric Gaussian line-shape is fitted during the irradiance calibration. Additionally, external parameters used in the tropospheric air mass factor computation (surface reflectances, cloud parameters and a priori profile shapes of H2CO have been updated using most recent databases. Similar updates were also applied to the historical datasets of GOME and SCIAMACHY, leading to the generation of a consistent multi-mission H2CO data record covering the time period from 1997 until 2011. Comparing the resulting time series of monthly averaged H2CO vertical columns in 12 large regions worldwide, the correlation coefficient between SCIAMACHY and GOME-2 columns is generally higher than 0.8 in the overlap period, and linear regression slopes differ by less than 10% from unity in most of the regions. In comparison to SCIAMACHY, the largely improved spatial sampling of GOME-2 allows for a better characterisation of formaldehyde distribution at the regional scale and

  6. Quantitative bias estimates for tropospheric NO2 columns retrieved from SCIAMACHY, OMI, and GOME-2 using a common standard for East Asia

    Irie, H.; Boersma, K. F.; Y. Kanaya; H. Takashima; Pan, X; Z. F. Wang

    2012-01-01

    For the intercomparison of tropospheric nitrogen dioxide (NO2) vertical column density (VCD) data from three different satellite sensors (SCIAMACHY, OMI, and GOME-2), we use a common standard to quantitatively evaluate the biases for the respective data sets. As the standard, a regression analysis using a single set of collocated ground-based Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) observations at several sites in Japan and China from 2006–2011 is adopted. Examinati...

  7. Evaluation of the operational Aerosol Layer Height retrieval algorithm for Sentinel-5 Precursor: application to O2 A band observations from GOME-2A

    A. F. J. Sanders; De Haan, J...F.; Sneep, M.; Apituley, A.; P. Stammes; M. O. Vieitez; Tilstra, L. G.; Tuinder, O. N. E.; C. E. Koning; J. P. Veefkind

    2015-01-01

    An algorithm setup for the operational Aerosol Layer Height product for TROPOMI on the Sentinel-5 Precursor mission is described and discussed, applied to GOME-2A data, and evaluated with lidar measurements. The algorithm makes a spectral fit of reflectance at the O2 A band in the near-infrared and the fit window runs from 758 to 770 nm. The aerosol profile is parameterised by a scattering layer with constant aerosol volume extinction coef...

  8. Evaluation of the operational Aerosol Layer Height retrieval algorithm for Sentinel-5 Precursor: application to O2 A band observations from GOME-2A

    A. F. J. Sanders; De Haan, J...F.; Sneep, M.; Apituley, A.; P. Stammes; M. O. Vieitez; Tilstra, L. G.; Tuinder, O. N. E.; C. E. Koning; J. P. Veefkind

    2015-01-01

    An algorithm setup for the operational Aerosol Layer Height product for TROPOMI on the Sentinel-5 Precursor mission is described and discussed, applied to GOME-2A data, and evaluated with lidar measurements. The algorithm makes a spectral fit of reflectance at the O2 A band in the near-infrared and the fit window runs from 758 to 770 nm. The aerosol profile is parameterized by a scattering layer with constant aerosol volume extinction coef...

  9. Ozonvertikalverteilungen aus UV/Vis-Nadirspektren des Satelliteninstrumentes GOME:Optimierung und Sensitivitätsstudien zur Nutzung der achtjährigen Messreihen

    Tellmann, Silvia

    2004-01-01

    The stratospheric ozone layer protects the biosphere from the effects of harmful ultraviolet radiation and is responsible for the temperature structure of the stratosphere. The severe changes of the ozone layer during the last decades clarified the need to monitor the variation of ozone concentrations.The Global Ozone Monitoring Experiment (GOME) which was launched in April 1995 onboard ESA´s second European Remote Sensing Satellite (ERS-2) enables us to investigate height resolved ozone dist...

  10. First quantitative bias estimates for tropospheric NO2 columns retrieved from SCIAMACHY, OMI, and GOME-2 using a common standard

    Pan, X; H. Takashima; Y. Kanaya; Boersma, K. F.; Irie, H.; Z. F. Wang

    2012-01-01

    For the intercomparison of tropospheric nitrogen dioxide NO2 vertical column density (VCD) data from three different satellite sensors (SCIAMACHY, OMI, and GOME-2), we use a common standard to quantitatively evaluate the biases for the respective data sets. As the standard, a regression analysis using a single set of collocated ground-based Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) observations at several sites in Japan and China in 2006–2011 is adopted. Examination o...

  11. Formaldehyde and nitrogen dioxide over the remote western Pacific Ocean: SCIAMACHY and GOME-2 validation using ship-based MAX-DOAS observations

    Peters, E.; Wittrock, F.; K. Großmann; Frieß, U.; Richter, A; J. P. Burrows

    2012-01-01

    In October 2009, shipborne Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) measurements were performed during the TransBrom campaign over the western Pacific Ocean (≈ 40° N to 20° S). Vertical tropospheric trace gas columns and profiles of nitrogen dioxide (NO2) and formaldehyde (HCHO) as well as stratospheric NO2 columns were retrieved in order to validate corresponding measurements from the GOME-2 and SCIA...

  12. Tropospheric O3 over Indonesia during biomass burning events measured with GOME (Global Ozone Monitoring Experiment) and compared with trajectory analysis

    Wittrock, F.; Richter, A; J. Meyer-Arnek; Ladstätter-Weißenmayer, A.; Burrows, J.P.

    2005-01-01

    Tropospheric ozone columns of up to 50 DU were observed by GOME (Global Ozone Monitoring Experiment) above Indonesia in September 1997, while only background amounts were measured in September 1998. The Traj.x trajectory model along with BRemen's Atmospheric PHOtochemical model (BRAPHO) were used to investigate the higher than average ozone columns above Indonesia. The transport analysis reveals that biomass burning over central Africa and northern Australia does not significantly influence o...

  13. Influence of stratospheric airmasses on tropospheric vertical O3 columns based on GOME (Global Ozone Monitoring Experiment measurements and backtrajectory calculation over the Pacific

    A. Ladstätter-Weißenmayer

    2004-01-01

    Full Text Available Satellite based GOME (Global Ozone Measuring experiment data are used to characterize the amount of tropospheric ozone over the tropical Pacific. Tropospheric ozone was determined from GOME data using the Tropospheric Excess Method (TEM. In the tropical Pacific a significant seasonal variation is detected. Tropospheric excess ozone is enhanced during the biomass burning season from September to November due to outflow from the continents. In September 1999 GOME data reveal an episode of increased excess ozone columns over Tahiti (18.0° S; 149.0° W (Eastern Pacific compared to Am. Samoa (14.23° S; 170.56° W and Fiji (18.13° S; 178.40° E, both situated in the Western Pacific. Backtrajectory calculations show that none of the airmasses arriving over the three locations experienced anthropogenic pollution (e. g. biomass burning. Consequently other sources of ozone have to be considered. One possible process leading to an increase of tropospheric ozone is stratosphere-troposphere-exchange. An analysis of the potential vorticity along trajectories arriving above each of the locations reveals that airmasses at Tahiti are subject to enhanced stratospheric influence, compared to Am. Samoa and Fiji. As a result this study shows clear incidents of transport of airmasses from the stratosphere into the troposphere.

  14. Volcanic SO2 fluxes derived from satellite data: a survey using OMI, GOME-2, IASI and MODIS

    N. Theys

    2013-06-01

    Full Text Available Sulphur dioxide (SO2 fluxes of active degassing volcanoes are routinely measured with ground-based equipment to characterize and monitor volcanic activity. SO2 of unmonitored volcanoes or from explosive volcanic eruptions, can be measured with satellites. However, remote-sensing methods based on absorption spectroscopy generally provide integrated amounts of already dispersed plumes of SO2 and satellite derived flux estimates are rarely reported. Here we review a number of different techniques to derive volcanic SO2 fluxes using satellite measurements of plumes of SO2 and investigate the temporal evolution of the total emissions of SO2 for three very different volcanic events in 2011: Puyehue-Cordón Caulle (Chile, Nyamulagira (DR Congo and Nabro (Eritrea. High spectral resolution satellite instruments operating both in the ultraviolet-visible (OMI/Aura and GOME-2/MetOp-A and thermal infrared (IASI/MetOp-A spectral ranges, and multispectral satellite instruments operating in the thermal infrared (MODIS/Terra-Aqua are used. We show that satellite data can provide fluxes with a sampling of a day or less (few hours in the best case. Generally the flux results from the different methods are consistent, and we discuss the advantages and weaknesses of each technique. Although the primary objective of this study is the calculation of SO2 fluxes, it also enables us to assess the consistency of the SO2 products from the different sensors used.

  15. Anticorpos para enterovirus na localidade de Ferreira Gomes, no Território Federal do Amapá

    Hermann G. Schatzmayr

    1972-02-01

    Full Text Available Sôros coletados no Território Federal do Amapá, localidade de Ferreira Gomes, foram, testados para anticorpos neutralizantes de enterovírus Poliovírus 1, 2 e 3 e Coxsackie B1 a B6, em população autóctone. Os resultados apresentados na Tabela 1, indicam alta circulação do vírus da poliomielite na região atingindo-se níveis tão elevados como em escolares do Estado da Guanabara. Em relação a Coxsackie B, alcançaram-se também resultados semelhantes nas duas populações exceto com Coxsackie B., o qual apresentou-se em valôres bem mais altos nos sôros coletados na região norte. Os autores chamam atenção da necessidade de vacinação contra a poliomielite de grandes segmentos da população susceptível em curto prazo, tendo em vista a ampla disseminação das infecções por poliovírus em tôdas as regiões do país onde forem pesquisadas.

  16. Evaluation of satellite sulphur dioxide estimates from OMI/Aura, SCIAMACHY/Envisat and GOME2/MetopA

    Koukouli, MariLiza; Balis, Dimitris; Theys, Nicolas; Brenot, Hugues; van Gent, Jeroen; Valks, Pieter; Hedelt, Pascal; Lichtenberg, Günter; Richter, Andreas; Krotkov, Nickolay; van der A, Ronald

    2015-04-01

    The EU FP7 Monitoring and Assessment of Regional air quality in China using space Observations, Project Of Long-term sino-european co-Operation, MarcoPolo, project focuses on deriving emission estimates from space and their refinement by spatial downscaling and by source sector apportionment. Satellite observations of suphur dioxide, SO2, over the greater China area are analyzed using novel techniques [Fioletov et al., 2011; 2013] in order to enhance the observational signal and provide a robust SO2 dataset for the region. Observations from the SCIAMACHY/Envisat, GOME2/MetopA and OMI/Aura missions are assessed in this work and their relative strengths and shortcomings discussed at length. Rigorous screening is applied to and presented for each data source, including a full length spatiotemporal statistical analysis. Furthermore, identification of point sources such as power plants and urban agglomerations, as well as the definition of their relative contribution to the general SO2 levels, form the basis of this investigation.

  17. OMI/Aura, SCIAMACHY/Envisat and GOME2/MetopA Sulphur Dioxide Estimate; The Case of Eastern Asia

    Koukouli, M. E.; Balis, D. S.; Theys, N.; Brenot, H.; van Gent, J.; Hendrick, F.; Wang, T.; Valks, P.; Hedelt, P.; Lichtenberg, G.; Richter, A.; Krotkov, N.; Li, C.; van der A, R.

    2015-06-01

    The EU FP7 Monitoring and Assessment of Regional air quality in China using space Observations, Project Of Long-term sino-european co-Operation, MarcoPolo, project focuses on deriving emission estimates from space, http://www.marcopolo-panda.eu. Long term satellite observations of Sulphur Dioxide, SO2, over the greater China area from the SCIAMACHY/Envisat, GOME2/MetopA and OMI/Aura missions are compared and their relative strong points and limitations are discussed. For each satellite instrument, two different datasets are being analyzed in the same manner. Rigorous spatiotemporal statistical analysis based on novel analysis techniques is performed for each data set in order to reduce noise and biases and enhance pollution signals in satellite datasets. Furthermore, identification of point sources such as power plants, smelters and urban agglomerations, as well as definition of their relative contribution to the regional SO2 levels, form the main findings of this investigation. Trend analyses and their statistical representation help locate regions of interesting SO2 loading in China.

  18. Investigation of NOx emissions and NOx-related chemistry in East Asia using CMAQ-predicted and GOME-derived NO2 columns

    J. Y. Kim

    2009-02-01

    Full Text Available In this study, NO2 columns from the US EPA Models-3/CMAQ model simulations carried out using the 2001 ACE-ASIA (Asia Pacific Regional Aerosol Characterization Experiment emission inventory over East Asia were compared with the GOME-derived NO2 columns. There were large discrepancies between the CMAQ-predicted and GOME-derived NO2 columns in the fall and winter seasons. In particular, while the CMAQ-predicted NO2 columns produced larger values than the GOME-derived NO2 columns over South Korea for all four seasons, the CMAQ-predicted NO2 columns produced smaller values than the GOME-derived NO2 columns over North China for all seasons with the exception of summer (summer anomaly. It is believed that there might be some error in the NOx emission estimates as well as uncertainty in the NOx chemical loss rates over North China and South Korea. Regarding the latter, this study further focused on the biogenic VOC (BVOC emissions that were strongly coupled with NOx chemistry during summer in East Asia. This study also investigated whether the CMAQ-modeled NO2/NOx ratios with the possibly overestimated isoprene emissions were higher than those with reduced isoprene emissions. Although changes in both the NOx chemical loss rates and NO2/NOx ratios from CMAQ-modeling with the different isoprene emissions affected the CMAQ-modeled NO2 levels, the effects were found to be limited, mainly due to the low absolute levels of NO2 in summer. Seasonal variations of the NOx emission fluxes over East Asia were further investigated by a set of sensitivity runs of the CMAQ model. Although the results still exhibited the summer anomaly possibly due to the uncertainties in both NOx-related chemistry in the CMAQ model and the GOME measurements, it is believed that consideration of both the seasonal variations in NOx emissions and the correct BVOC emissions in East Asia are critical. Overall, it is estimated that the NOx emissions are underestimated by ~57.3% in North

  19. Surface NO2 fields derived from joint use of OMI and GOME-2A observations with EMEP model output

    Schneider, Philipp; Svendby, Tove; Stebel, Kerstin

    2016-04-01

    Nitrogen dioxide (NO2) is one of the most prominent air pollutants. Emitted primarily by transport and industry, NO2 has a major impact on health and economy. In contrast to the very sparse network of air quality monitoring stations, satellite data of NO2 is ubiquitous and allows for quantifying the NO2 levels worldwide. However, one drawback of satellite-derived NO2 products is that they provide solely an estimate of the entire tropospheric column, whereas what is generally needed for air quality applications are the concentrations of NO2 near the surface. Here we derive surface NO2 concentration fields from OMI and GOME-2A tropospheric column products using the EMEP chemical transport model as auxiliary information. The model is used for providing information of the boundary layer contribution to the total tropospheric column. For preparation of deriving the surface product, a comprehensive model-based analysis of the spatial and temporal patterns of the NO2 surface-to-column ratio in Europe was carried out for the year 2011. The results from this analysis indicate that the spatial patterns of the surface-to-column ratio vary only slightly. While the highest ratio values can be found in some shipping lanes, the spatial variability of the ratio in some of the most polluted areas of Europe is not very high. Some but not all urban agglomeration shows high ratio values. Focusing on the temporal behavior, the analysis showed that the European-wide average ratio varies throughout the year. The surface-to-column ratio increases from January all the way through April when it reaches its maximum, then decreases relatively rapidly to average levels and then stays mostly constant throughout the summer. The minimum ratio is observed in December. The knowledge gained from analyzing the spatial and temporal patterns of the surface-to-column ratio was then used to produce surface NO2 products from the daily NO2 data for OMI and GOME-2A. This was carried out using two methods

  20. SO2 and BrO observation in the plume of the Eyjafjallajökull volcano 2010: CARIBIC and GOME-2 retrievals

    P. F. J. van Velthoven

    2010-12-01

    Full Text Available The ash cloud of the Eyjafjallajökull1 volcano on Iceland caused closure of large parts of European airspace in April and May 2010. For the validation and improvement of the European volcanic ash forecast models several research flights were performed. Also the CARIBIC (Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrument Container flying laboratory, which routinely measures at cruise altitude (≈11 km performed three dedicated measurements flights through sections of the ash plume. Although the focus of these flights was on the detection and quantification of the volcanic ash, we report here on sulphur dioxide (SO2 and bromine monoxide (BrO measurements with the CARIBIC DOAS (Differential Optical Absorption Spectroscopy instrument during the second of these special flights on 16 May 2010. As the BrO and the SO2 observations coincide, we assume the BrO to have been formed inside the volcanic plume. Both SO2 and BrO observations agree well with simultaneous satellite (GOME-2 observations. SO2 column densities retrieved from satellite observations are often used as an indicator for volcanic ash. For SO2 some additional information on the local distribution can be derived from a~comparison of forward and back scan GOME-2 data. More details on the local plume size and position are retrieved by combining CARIBIC and GOME-2 data. 1Also referred to as: Eyjafjalla (e.g. Schumann et al., 2010, Eyjafjöll or Eyjafjoll (e.g. Ansmann et al., 2010.

  1. SO2 and BrO observation in the plume of the Eyjafjallajökull volcano 2010: CARIBIC and GOME-2 retrievals

    P. F. J. van Velthoven

    2011-03-01

    Full Text Available The ash cloud of the Eyjafjallajökull (also referred to as: Eyjafjalla (e.g. Schumann et al., 2011, Eyjafjöll or Eyjafjoll (e.g. Ansmann et al., 2010 volcano on Iceland caused closure of large parts of European airspace in April and May 2010. For the validation and improvement of the European volcanic ash forecast models several research flights were performed. Also the CARIBIC (Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrument Container flying laboratory, which routinely measures at cruise altitude (≈11 km performed three dedicated measurements flights through sections of the ash plume. Although the focus of these flights was on the detection and quantification of the volcanic ash, we report here on sulphur dioxide (SO2 and bromine monoxide (BrO measurements with the CARIBIC DOAS (Differential Optical Absorption Spectroscopy instrument during the second of these special flights on 16 May 2010. As the BrO and the SO2 observations coincide, we assume the BrO to have been formed inside the volcanic plume. Average SO2 and BrO mixing ratios of ≈40 ppb and ≈5 ppt respectively are retrieved inside the plume. The BrO to SO2 ratio retrieved from the CARIBIC observation is ≈1.3×10−4. Both SO2 and BrO observations agree well with simultaneous satellite (GOME-2 observations. SO2 column densities retrieved from satellite observations are often used as an indicator for volcanic ash. As the CARIBIC O4 column densities changed rapidly during the plume observation, we conclude that the aerosol and the SO2 plume are collocated. For SO2 some additional information on the local distribution can be derived from a comparison of forward and back scan GOME-2 data. More details on the local plume size and position are retrieved by combining CARIBIC and GOME-2 data.

  2. Global Monitoring of Terrestrial Chlorophyll Fluorescence from Moderate-spectral-resolution Near-infrared Satellite Measurements: Methodology, Simulations, and Application to GOME-2

    Joiner, J.; Gaunter, L.; Lindstrot, R.; Voigt, M.; Vasilkov, A. P.; Middleton, E. M.; Huemmrich, K. F.; Yoshida, Y.; Frankenberg, C.

    2013-01-01

    Globally mapped terrestrial chlorophyll fluorescence retrievals are of high interest because they can provide information on the functional status of vegetation including light-use efficiency and global primary productivity that can be used for global carbon cycle modeling and agricultural applications. Previous satellite retrievals of fluorescence have relied solely upon the filling-in of solar Fraunhofer lines that are not significantly affected by atmospheric absorption. Although these measurements provide near-global coverage on a monthly basis, they suffer from relatively low precision and sparse spatial sampling. Here, we describe a new methodology to retrieve global far-red fluorescence information; we use hyperspectral data with a simplified radiative transfer model to disentangle the spectral signatures of three basic components: atmospheric absorption, surface reflectance, and fluorescence radiance. An empirically based principal component analysis approach is employed, primarily using cloudy data over ocean, to model and solve for the atmospheric absorption. Through detailed simulations, we demonstrate the feasibility of the approach and show that moderate-spectral-resolution measurements with a relatively high signal-to-noise ratio can be used to retrieve far-red fluorescence information with good precision and accuracy. The method is then applied to data from the Global Ozone Monitoring Instrument 2 (GOME-2). The GOME-2 fluorescence retrievals display similar spatial structure as compared with those from a simpler technique applied to the Greenhouse gases Observing SATellite (GOSAT). GOME-2 enables global mapping of far-red fluorescence with higher precision over smaller spatial and temporal scales than is possible with GOSAT. Near-global coverage is provided within a few days. We are able to show clearly for the first time physically plausible variations in fluorescence over the course of a single month at a spatial resolution of 0.5 deg × 0.5 deg

  3. City and School: the Visible Construction of the Fernando Gomes Elementary School in Porto Alegre/RS - Brazil (1913-1935)

    Tatiane De Freitas Ermel

    2016-01-01

    In the context of studies about space and school architecture, this article analyses the visual construction of the Fernando Gomes Elementary School, which was located in downtown Porto Alegre/RS, Brazil between 1913 and 1935. Designed by the engineer Afonso Hébert, head of the Department of Public Works in the State of Rio Grande do Sul/RS, the building was completed in 1922. In addition to functional elements, i.e., a large number of classrooms that would serve to increase the access of chi...

  4. Formaldehyde and nitrogen dioxide over the remote western Pacific Ocean: SCIAMACHY and GOME-2 validation using ship-based MAX-DOAS observations

    E. Peters

    2012-11-01

    Full Text Available In October 2009, shipborne Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS measurements were performed during the TransBrom campaign over the western Pacific Ocean (≈ 40° N to 20° S. Vertical tropospheric trace gas columns and profiles of nitrogen dioxide (NO2 and formaldehyde (HCHO as well as stratospheric NO2 columns were retrieved in order to validate corresponding measurements from the GOME-2 and SCIAMACHY satellite instruments and to estimate tropospheric background concentrations of these trace gases.

    All instruments reproduced the same characteristic, latitude-dependent shape of stratospheric NO2. SCIAMACHY and GOME-2 data differ by about 1% from each other while yielding lower vertical columns than MAX-DOAS morning values as a consequence of measurement time and stratospheric NO2 diurnal cycle. Due to this diurnal cycle, an increase of 8.7 ± 0.5 × 1013 molec cm−2 h−1 of stratospheric NO2 was estimated from MAX-DOAS data at low latitudes during the day.

    Tropospheric NO2 was above the detection limit only in regions of higher anthropogenic impact (ship traffic, transport of pollution from land. A background column of 1.3 × 1014 molec cm−2 (or roughly 50 ppt boundary layer concentration can be estimated as upper limit for the remote ocean, which is in agreement with GOME-2 monthly mean values. In the marine boundary layer close to the islands of Hokkaido and Honshu, up to 0.8 ppbv were retrieved close to the surface.

    Background HCHO concentrations over the remote ocean exhibit a diurnal cycle with maximum values (depending strongly on weather conditions of 4 × 1015 molec cm−2 for the vertical column at noontime. Corresponding peak concentrations of up to 1.1 ppbv were retrieved in elevated altitudes (≈ 400 m around noon while maximum

  5. Global observations of glyoxal columns from OMI/Aura and GOME-2/Metop-A sensors and comparison with multi-year simulations by the IMAGES model

    Lerot, Christophe; Stavrakou, Trissevgeni; Hendrick, François; De Smedt, Isabelle; Müller, Jean-François; Volkamer, Rainer; Van Roozendael, Michel

    2015-04-01

    Volatile organic compounds (VOCs) originating from both natural and human activities play a key role in air quality. Information on their atmospheric concentrations can be derived using remote sensing techniques for a limited number of species, including formaldehyde (HCHO) and glyoxal (CHOCHO). The latter is mostly produced in the atmosphere as an intermediate product in the oxidation of other non-methane VOCs. It is also directly emitted from fire events and combustion processes. Owing to its short lifetime, elevated glyoxal concentrations are observed near emission sources. Measurements of atmospheric glyoxal concentrations therefore provide quantitative information on the different types of VOC emission and can help to better assess the quality of current inventories. In addition, glyoxal is also known to significantly contribute to the total budget of secondary organic aerosols. Global observations of glyoxal columns have been realized from different space-borne spectrometers using the well-known DOAS retrieval technique. In the past, we developed an algorithm to retrieve glyoxal columns from spectra measured by the GOME-2 instrument aboard METOP-A (Lerot et al., 2010). Specificities of this algorithm were an original two-step approach in the DOAS fit to minimize the impact of spectral interferences with the liquid water absorption as well as the use of a priori information from the Chemical Transport Model IMAGES in the air mass factor calculation. In this work, we present the adaptation of this algorithm to the OMI sensor on the AURA platform. The time series of glyoxal columns derived from OMI and GOME-2 are compared in different parts of the world and a high level of consistency is found. The OMI glyoxal data product is found to be very stable over the entire duration of the mission, in contrast to the GOME-2 product which is affected by instrumental degradation. We present validation results using several years of MAX-DOAS glyoxal measurements

  6. Quantitative bias estimates for tropospheric NO2 columns retrieved from SCIAMACHY, OMI, and GOME-2 using a common standard for East Asia

    X. Pan

    2012-10-01

    Full Text Available For the intercomparison of tropospheric nitrogen dioxide (NO2 vertical column density (VCD data from three different satellite sensors (SCIAMACHY, OMI, and GOME-2, we use a common standard to quantitatively evaluate the biases for the respective data sets. As the standard, a regression analysis using a single set of collocated ground-based Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS observations at several sites in Japan and China from 2006–2011 is adopted. Examinations of various spatial coincidence criteria indicates that the slope of the regression line can be influenced by the spatial distribution of NO2 over the area considered. While the slope varies systematically with the distance between the MAX-DOAS and satellite observation points around Tokyo in Japan, such a systematic dependence is not clearly seen and correlation coefficients are generally higher in comparisons at sites in China. On the basis of these results, we focus mainly on comparisons over China and estimate the biases in SCIAMACHY, OMI, and GOME-2 data (TM4NO2A and DOMINO version 2 products against the MAX-DOAS observations to be −5 ± 14%, −10 ± 14%, and +1 ± 14%, respectively, which are all small and insignificant. We suggest that these small biases now allow for analyses combining these satellite data for air quality studies, which are more systematic and quantitative than previously possible.

  7. Quantitative bias estimates for tropospheric NO2 columns retrieved from SCIAMACHY, OMI, and GOME-2 using a common standard for East Asia

    Irie, H.; Boersma, F.; Kanaya, Y.; Takashima, H.; Xiaole, P.; Wang, Z.

    2012-12-01

    For the intercomparison of tropospheric nitrogen dioxide (NO2) vertical column density (VCD) data from three different satellite sensors (SCIAMACHY, OMI, and GOME-2), we use a common standard to quantitatively evaluate the biases for the respective data sets. As the standard, a regression analysis using a single set of collocated ground-based Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) observations at several sites in Japan and China in 2006-2011 is adopted. Examination of various spatial coincidence criteria indicates that the slope of the regression line can be influenced by the spatial distribution of NO2 over the area considered. While the slope varies systematically with the distance between the MAX-DOAS and satellite observation points around Tokyo in Japan, such a systematic dependence is not clearly seen and correlation coefficients are generally higher in comparisons at sites in China. On the basis of these results, we focus mainly on comparisons over China and best estimate the biases in SCIAMACHY, OMI, and GOME-2 data (TM4NO2A and DOMINO version 2 products) against the MAX-DOAS observations to be -5±14%, -10±14%, and +1±14%, respectively, which are all small and insignificant. We suggest that these small biases now allow analyses combining these satellite data for air quality studies that are more systematic and quantitative than previously possible.

  8. Investigation of NOx emissions and NOx-related chemistry in East Asia using CMAQ-predicted and GOME-derived NO2 columns

    J. H. Woo

    2008-09-01

    Full Text Available This study examined the estimation accuracy of NOx emissions over East Asia with particular focus on North China and South Korea due to their strong source (North China-receptor (South Korea relationship. In order to determine contributions of North China emissions to South Korean air quality accurately, it is important to examine the accuracy of the emission inventories of both regions. In this study, NO2 columns from the US EPA Models-3/CMAQ model simulations carried out using the 2001 ACE-ASIA (Asia Pacific Regional Aerosol Characterization Experiment emission inventory over East Asia were compared with the GOME-derived NO2 columns. There were large discrepancies between the CMAQ-predicted and GOME-derived NO2 columns in the fall and winter seasons. In particular, while the CMAQ-predicted NO2 columns produced larger values than the GOME-derived NO2 columns over South Korea (receptor region for all four seasons, the CMAQ-predicted NO2 columns produced smaller values than the GOME-derived NO2 columns over North China (source region for all seasons with the exception of summer. It is believed that there might be some estimation error in the NOx emissions as well as large uncertainty in NOx loss rates over North China and South Korea. Regarding the latter, this study further focused on the biogenic VOC emissions that were strongly coupled with NOx chemistry in East Asia. It was found that the rates of NOx loss determined by CMAQ modeling studies might be significantly low due to the possible overestimation of biogenic isoprene emissions during summer, particularly in China. In addition, due to the possible overestimation of isoprene emissions, the CMAQ-modeled NO2/NOx ratios might show an incorrectly high level, compared with the actual NO2/NOx ratios. In addition to the retarded NOx chemical loss rates and overestimated NO2/NOx ratios, the omission of soil NOx emissions over North China during summer can lead to an underestimation of NOx

  9. Diversity and genetic structure in natural populations of Hancornia speciosa var. speciosa Gomes in northeastern Brazil Diversidade e estrutura genética em populações naturais de Hancornia speciosa var. speciosa Gomes no nordeste do Brasil

    Georgia Vilela Martins

    2012-12-01

    Full Text Available Hancornia speciosa Gomes is a fruit tree native from Brazil that belongs to Apocinaceae family, and is popularly known as Mangabeira. Its fruits are widely consumed raw or processed as fruit jam, juices and ice creams, which have made it a target of intense exploitation. The extractive activities and intense human activity on the environment of natural occurrence of H. speciosa has caused genetic erosion in the species and little is known about the ecology or genetic structure of natural populations. The objective of this research was the evaluation of the genetic diversity and genetic structure of H. speciosa var. speciosa. The genetic variability was assessed using 11 allozyme loci with a sample of 164 individuals distributed in six natural populations located in the States of Pernambuco and Alagoas, Northeastern Brazil. The results showed a high level of genetic diversity within the species (e= 0.36 seeing that the most of the genetic variability of H. speciosa var. speciosa is within its natural populations with low difference among populations ( or = 0.081. The inbreeding values within ( = -0.555 and among populations ( =-0.428 were low showing lacking of endogamy and a surplus of heterozygotes. The estimated gene flow ( m was high, ranging from 2.20 to 13.18, indicating to be enough to prevent the effects of genetic drift and genetic differentiation among populations. The multivariate analyses indicated that there is a relationship between genetic and geographical distances, which was confirmed by a spatial pattern analysis using Mantel test (r = 0.3598; p = 0.0920 with 1000 random permutations. The high genetic diversity index in these populations indicates potential for in situ genetic conservation.Hancornia speciosa Gomes é uma árvore frutífera nativa do Brasil, pertencente à família Apocinaceae, e é conhecida popularmente como Mangabeira. Seus frutos são amplamente consumidos in natura ou processados como sucos, sorvetes e

  10. A Rapid Method for Determination of Some Phenolic Acids in Brazilian Tropical Fruits of Mangaba (Hancornia speciosa Gomes) and Umbu (Spondias tuberosa Arruda Camara) by UPLC

    Edelvio de Barros Gomes; Suyare Araújo Ramalho; Nayjara Carvalho Gualberto; Rita de Cássia Mendonça de Miranda; Nisha Nigam; Narendra Narain

    2013-01-01

    A rapid chromatographic method for the determination of six phenolic acids (chlorogenic, ferulic, gallic, p-coumaric, protocatechuic and vanillic acids) by ultra performance liquid chromatography (UPLC), was developed and applied for Brazilian tropical fruits mangaba (Hancornia speciosa Gomes) and umbu (Spondias tuberosa Arruda Camara). A multivariate statistical experimental design was employed to optimize analytical conditions (solvent A, solvent B concentrations a...

  11. Paulo Emílio Salles Gomes e a transformação de crônicas em uma história do cinema brasileiro: os casos do nascimento e da bela época = Paulo Emilio Salles Gomes and processing in a chronic history of brazilian cinema: the cases of birth and beautiful epoch

    Morais, Julierme

    2014-01-01

    Full Text Available Procuraremos demonstrar como o crítico e historiador do cinema brasileiro Paulo Emílio Salles Gomes, na obra Panorama do cinema brasileiro: 1896/1966 (1966, promoveu a transposição de crônicas do cinema brasileiro para uma história de nossa atividade cinematográfica, sobretudo com relação ao tema do nascimento do cinema brasileiro e ao conceito de Bela época aplicado a determinado período de nossa história cinematográfica.

  12. Multi-model ensemble simulations of tropospheric NO2 compared with GOME retrievals for the year 2000

    T. P. C. van Noije

    2006-01-01

    Full Text Available We present a systematic comparison of tropospheric NO2 from 17 global atmospheric chemistry models with three state-of-the-art retrievals from the Global Ozone Monitoring Experiment (GOME for the year 2000. The models used constant anthropogenic emissions from IIASA/EDGAR3.2 and monthly emissions from biomass burning based on the 1997–2002 average carbon emissions from the Global Fire Emissions Database (GFED. Model output is analyzed at 10:30 local time, close to the overpass time of the ERS-2 satellite, and collocated with the measurements to account for sampling biases due to incomplete spatiotemporal coverage of the instrument. We assessed the importance of different contributions to the sampling bias: correlations on seasonal time scale give rise to a positive bias of 30–50% in the retrieved annual means over regions dominated by emissions from biomass burning. Over the industrial regions of the eastern United States, Europe and eastern China the retrieved annual means have a negative bias with significant contributions (between –25% and +10% of the NO2 column resulting from correlations on time scales from a day to a month. We present global maps of modeled and retrieved annual mean NO2 column densities, together with the corresponding ensemble means and standard deviations for models and retrievals. The spatial correlation between the individual models and retrievals are high, typically in the range 0.81–0.93 after smoothing the data to a common resolution. On average the models underestimate the retrievals in industrial regions, especially over eastern China and over the Highveld region of South Africa, and overestimate the retrievals in regions dominated by biomass burning during the dry season. The discrepancy over South America south of the Amazon disappears when we use the GFED emissions specific to the year 2000. The seasonal cycle is analyzed in detail for eight different continental regions. Over regions dominated by

  13. Transport and build-up of tropospheric trace gases during the MINOS campaign: comparision of GOME, in situ aircraft measurements and MATCH-MPIC-data

    A. Ladstätter-Weißenmayer

    2003-01-01

    Full Text Available The MINOS (Mediterranean INtensive Oxidant Study campaign was an international, multi-platform field campaign to measure long-range transport of air-pollution and aerosols from South East Asia and Europe towards the Mediterranean basin during August 2001. High pollution events were observed during this campaign. For the Mediterranean region enhanced tropospheric nitrogen dioxide (NO2 and formaldehyde (HCHO, which are precursors of tropospheric ozone (O3, were detected by the satellite based GOME (Global Ozone Monitoring Experiment instrument and compared with airborne in situ measurements as well as with the output from the global 3D photochemistry-transport model MATCH-MPIC (Model of Atmospheric Transport and CHemistry - Max Planck Institute for Chemistry. The increase of pollution in that region leads to severe air quality degradation with regional and global implications.

  14. Evaluation of the operational Aerosol Layer Height retrieval algorithm for Sentinel-5 Precursor: application to O2 A band observations from GOME-2A

    A. F. J. Sanders

    2015-06-01

    Full Text Available An algorithm setup for the operational Aerosol Layer Height product for TROPOMI on the Sentinel-5 Precursor mission is described and discussed, applied to GOME-2A data, and evaluated with lidar measurements. The algorithm makes a spectral fit of reflectance at the O2 A band in the near-infrared and the fit window runs from 758 to 770 nm. The aerosol profile is parameterized by a scattering layer with constant aerosol volume extinction coefficient and aerosol single scattering albedo and with a fixed pressure thickness. The algorithm's target parameter is the height of this layer. In this paper, we apply the algorithm to observations from GOME-2A in a number of systematic and extensive case studies and we compare retrieved aerosol layer heights with lidar measurements. Aerosol scenes cover various aerosol types, both elevated and boundary layer aerosols, and land and sea surfaces. The aerosol optical thicknesses for these scenes are relatively moderate. Retrieval experiments with GOME-2A spectra are used to investigate various sensitivities, in which particular attention is given to the role of the surface albedo. From retrieval simulations with the single-layer model, we learn that the surface albedo should be a fit parameter when retrieving aerosol layer height from the O2 A band. Current uncertainties in surface albedo climatologies cause biases and non-convergences when the surface albedo is fixed in the retrieval. Biases disappear and convergence improves when the surface albedo is fitted, while precision of retrieved aerosol layer pressure is still largely within requirement levels. Moreover, we show that fitting the surface albedo helps to ameliorate biases in retrieved aerosol layer height when the assumed aerosol model is inaccurate. Subsequent retrievals with GOME-2A spectra confirm that convergence is better when the surface albedo is retrieved simultaneously with aerosol parameters. However, retrieved aerosol layer pressures are

  15. Evaluation of the operational Aerosol Layer Height retrieval algorithm for Sentinel-5 Precursor: application to O2 A band observations from GOME-2A

    Sanders, A. F. J.; de Haan, J. F.; Sneep, M.; Apituley, A.; Stammes, P.; Vieitez, M. O.; Tilstra, L. G.; Tuinder, O. N. E.; Koning, C. E.; Veefkind, J. P.

    2015-11-01

    An algorithm setup for the operational Aerosol Layer Height product for TROPOMI on the Sentinel-5 Precursor mission is described and discussed, applied to GOME-2A data, and evaluated with lidar measurements. The algorithm makes a spectral fit of reflectance at the O2 A band in the near-infrared and the fit window runs from 758 to 770 nm. The aerosol profile is parameterised by a scattering layer with constant aerosol volume extinction coefficient and aerosol single scattering albedo and with a fixed pressure thickness. The algorithm's target parameter is the height of this layer. In this paper, we apply the algorithm to observations from GOME-2A in a number of systematic and extensive case studies, and we compare retrieved aerosol layer heights with lidar measurements. Aerosol scenes cover various aerosol types, both elevated and boundary layer aerosols, and land and sea surfaces. The aerosol optical thicknesses for these scenes are relatively moderate. Retrieval experiments with GOME-2A spectra are used to investigate various sensitivities, in which particular attention is given to the role of the surface albedo. From retrieval simulations with the single-layer model, we learn that the surface albedo should be a fit parameter when retrieving aerosol layer height from the O2 A band. Current uncertainties in surface albedo climatologies cause biases and non-convergences when the surface albedo is fixed in the retrieval. Biases disappear and convergence improves when the surface albedo is fitted, while precision of retrieved aerosol layer pressure is still largely within requirement levels. Moreover, we show that fitting the surface albedo helps to ameliorate biases in retrieved aerosol layer height when the assumed aerosol model is inaccurate. Subsequent retrievals with GOME-2A spectra confirm that convergence is better when the surface albedo is retrieved simultaneously with aerosol parameters. However, retrieved aerosol layer pressures are systematically low (i

  16. Dynamical contibution of Mean Potential Vorticity pseudo-observations derived from MetOp/GOME2 Ozone data into weather forecast, a Mediterranean High Precipitation Event study.

    Sbii, Siham; Zazoui, Mimoun; Semane, Noureddine

    2015-04-01

    In the absence of observations covering the upper troposphere - lower stratophere, headquarters of several disturbances, and knowing that satellites are uniquely capable of providing uniform data coverage globally, a methodology is followed [1] to convert Total Column Ozone, observed by MetOp/GOME2, into pseudo-observations of Mean Potential Vorticity (MPV). The aim is to study the dynamical impact of Ozone data in the prediction of a Mediterranean Heavy Precipitation Event observed during 28-29 September 2012 in the context of HYMEX1. This study builds on a previously described methodology [2] that generates numerical weather prediction model initial conditions from ozone data. Indeed, the assimilation of MPV in a 3D-var framework is based on a linear regression between observed Ozone and vertical integrated Ertel PV. The latter is calculated using dynamical fields from the moroccan operational limited area model ALADIN-MAROC according to [3]: δθ fp p0 -R δU δV P V = - gξaδp- g-R-(p )Cp [(δp-)2 + (δp-)2] (1) Where ξa is the vertical component of the absolute vorticity, U and V the horizontal wind components, θ the potential temperature, R gas constant, Cp specific heat at constant pressure, p the pressure, p0 a reference pressure, g the gravity and f is the Coriolis parameter. The MPV is estimated using the following expression: --1--∫ P2 M PV = P1 - P2 P P V.δp 1 (2) With P1 = 500hPa and P2 = 100hPa In the present study, the linear regression is performed over September 2012 with a correlation coefficient of 0.8265 and is described as follows: M P V = 5.314610- 2 *O3 - 13.445 (3) where O3 and MPV are given in Dobson Unit (DU) and PVU (1 PV U = 10-6 m2 K kg-1 s-1), respectively. It is found that the ozone-influenced upper-level initializing fields affect the precipitation forecast, as diagnosed by a comparison with the ECMWF model. References [1] S. Sbii, N. Semane, Y. Michel, P. Arbogast and M. Zazoui (2012). Using METOP/GOME-2 data and MSG ozone

  17. Macrofauna associated with the brown algae Dictyota spp. (Phaeophyceae, Dictyotaceae) in the Sebastião Gomes Reef and Abrolhos Archipelago, Bahia, Brazil

    Cunha, Tauana Junqueira; Güth, Arthur Ziggiatti; Bromberg, Sandra; Sumida, Paulo Yukio Gomes

    2013-11-01

    The taxonomic richness and distributional patterns of the macrofauna associated with the algae genus Dictyota from the Abrolhos Bank (Eastern Brazilian coast) are analyzed. Macrofauna comprised a total of 9586 specimens; a complete faunal list of the most abundant taxa (Crustacea, Polychaeta and Mollusca, accounting for 95.6%) resulted in 64 families and 120 species. Forty six species are registered for the first time for the Abrolhos Bank, of which 3 are also new for the Brazilian coast. The most abundant families were Ampithoidae amphipods (with Ampithoe ramondi as the main faunal component), Janiridae isopods, Rissoellidae gastropods and Syllidae polychaetes. Comparisons were made between summer and winter periods and among sites from Sebastião Gomes Reef, near the coast, and from Siriba Island, in the Abrolhos Archipelago, away from the mainland. Algae size was lower in the summer, when faunal density was higher, suggesting a possible effect of grazing. Macrofaunal communities were significantly different among sites and periods. Coastal and external communities were markedly different and winter had the greatest effects on the fauna. Environmental conditions related to sediment type and origin and turbidity appear to be a good scenario for our macrofauna distribution results.

  18. City and School: the Visible Construction of the Fernando Gomes Elementary School in Porto Alegre/RS - Brazil (1913-1935

    Tatiane De Freitas Ermel

    2016-07-01

    Full Text Available In the context of studies about space and school architecture, this article analyses the visual construction of the Fernando Gomes Elementary School, which was located in downtown Porto Alegre/RS, Brazil between 1913 and 1935. Designed by the engineer Afonso Hébert, head of the Department of Public Works in the State of Rio Grande do Sul/RS, the building was completed in 1922. In addition to functional elements, i.e., a large number of classrooms that would serve to increase the access of children to primary school, its monumental proportions incorporated a series of symbolic elements aligned with the ideals of the First Brazilian Republic (1889–1930. The documentary analysis was performed on the archives of the Directorship of Public Education and the Directorship of Public Works of Rio Grande do Sul, as well as various iconographic sources, capital improvement plans and periodicals of the time. The construction of the school inaugurated a new conception of the space and architecture of public elementary schools in the State, as the visible improvement and sanitation of the cities were considered of great importance in the period. The construction of school buildings was also one of the greatest advertising tools of the new Republican political regime.

  19. Pimenta pseudocaryophyllus (Gomes Landrum: aspectos botânicos, ecológicos, etnobotânicos e farmacológicos

    A.S.R. D'angelis

    2014-09-01

    Full Text Available Pimenta pseudocaryophyllus (Gomes Landrum é a única espécie representante brasileira deste gênero de Myrtaceae. Tem sido popularmente utilizada no tratamento de diversas enfermidades, assim como condimento e aromatizante de bebidas, por seu sabor muito similar ao cravo-da-índia. Em menor escala, é empregada em carpintaria e na arborização urbana. Diversos autores analisaram a composição química do óleo essencial da espécie em diferentes regiões do Brasil, encontrando eugenol, metileugenol, (E metilisoeugenol, chavibetol, geranial e neral como composto predominante nos espécimes estudados. Visando ressaltar a importância de P. pseudocaryophyllus como potencial fonte de recursos assim como subsidiar ações de manejo adequado esta revisão apresenta os principais aspectos botânicos, ecológicos, etnobotânicos e farmacológicos da espécie.

  20. Tropospheric O3 over Indonesia during biomass burning events measured with GOME (Global Ozone Monitoring Experiment and compared with trajectory analysis

    F. Wittrock

    2005-05-01

    Full Text Available Tropospheric ozone columns of up to 50 DU were observed by GOME (Global Ozone Monitoring Experiment above Indonesia in September 1997, while only background amounts were measured in September 1998. The Traj.x trajectory model along with BRemen's Atmospheric PHOtochemical model (BRAPHO were used to investigate the higher than average ozone columns above Indonesia. The transport analysis reveals that biomass burning over central Africa and northern Australia does not significantly influence ozone columns over Indonesia in September 1997. El Niño conditions, leading to extreme dryness and uncontrolled fires in Indonesia, produced ozone precursors, which are initially only slowly advected westwards to the central Indian Ocean. Joint transport and chemistry modelling was able to reproduce the spatial distribution and amounts of ozone, NO2 and formaldehyde columns over Indonesia. The chemistry modelling shows a net production of 3.1 Tg of ozone produced by biomass burning in Indonesia in September 1997. Transport analysis further reveals that ozone columns over the Indian Ocean, between 10 and 20° S can be accounted for by the mixing of air masses containing NOx from lightning over the Congo Basin with air masses containing volatile organic compounds from biomass burning.

  1. USE OF SUBSTRATES FOR GROWING Hancornia speciosa Gomes SEEDLINGS IN PLASTIC TUBES SUBSTRATOS NA PRODUÇÃO DE MUDAS DE MANGABEIRA EM TUBETES

    Flávio Meneses Soares

    2011-04-01

    Full Text Available Mangabeira (Hancornia speciosa Gomes is a native fruit species from the Brazilian savannah. Its sexual propagation depends on a suitable substrate, because it interferes with seed germination and seedling establishment. The objective of this study was to evaluate the effect of different substrates for growing mangabeira seedlings in plastic tubes. The experiment was carried out in a greenhouse, in Cassilândia, Mato Grosso do Sul State, Brazil. The experimental design used was randomized blocks, with four replications and 15 seeds per plot. Five substrates were evaluated: A (washed sand + Plantmax® + soil, 1:1:3 v:v:v, B (carbonized rice husk + Plantmax® + soil, 1:1:3, C (carbonized rice husk + earthworm humus + soil, 1:1:3, D (bovine manure + Plantmax® + soil, 1:1:3, and E (bovine manure + soil, 2:3. The following parameters were evaluated: plant emergence percentage, emergence speed index, mortality percentage, seedling height, stem diameter, root length, number of leaves, chlorophyll leaf index, and shoot, root, and whole plant dry mass. From the results, substrates C, D, and E can be used for growing mangabeira seedlings in plastic tubes.

    A mangabeira (Hancornia speciosa Gomes é uma espécie frutífera nativa do Cerrado brasileiro. A propagação sexuada desta espécie depende de um substrato adequado, pois o mesmo interfere no processo germinativo e no estabelecimento da muda. Objetivou-se estudar o efeito de diferentes substratos na produção de mudas de mangabeira em tubetes. O trabalho foi conduzido em casa-de-vegetação, em Cassilândia (MS. O delineamento experimental foi em blocos casualizados, com quatro repetições e 15 plantas por parcela. Foram utilizados os seguintes substratos: A (areia lavada + Plantmax® + solo, na proporção de 1:1:3 v:v:v, B (casca de

  2. Vigo, vulgo Almereyda e Jean Vigo: Paulo Emílio Salles Gomes e a interlocução entre anarquismo e cinema

    Julierme Sebastião Morais

    2009-11-01

    StyleCount="156"> GOMES, Paulo Emílio Salles. Vigo, Vulgo Almereyda. São Paulo: Cosacnaify; Edições SESC-SP, 2009 (272p.; GOMES, Paulo Emílio Salles. Jean Vigo. São Paulo: Cosacnaify

  3. Chemical composition and severe ozone loss derived from SCIAMACHY and GOME-2 observations during Arctic winter 2010/2011 in comparisons to Arctic winters in the past

    R. Hommel

    2013-06-01

    Full Text Available Record breaking losses of ozone (O3 in the Arctic stratosphere have been reported in winter and spring 2011. Trace gas amounts and polar stratospheric cloud (PSC distributions retrieved using differential optical absorption spectroscopy (DOAS and scattering theory applied to the measurements of radiance and irradiance by satellite-born and ground-based instrumentation, document the unusual behaviour. A chemical transport model has been used to relate and compare Arctic winter-spring conditions in 2011 with those in previous years. We examine in detail the composition and transformations occurring in the Arctic polar vortex using total column and vertical profile data products for O3, bromine oxide (BrO, nitrogen dioxide (NO2, chlorine dioxide (OClO, and PSCs retrieved from measurements made by the instrument SCIAMACHY onboard the ESA satellite Envisat, as well as the total column ozone amount, retrieved from the measurements of GOME-2 on the EUMETSAT operational meteorological polar orbiter Metop-A. In the late winter and spring 2010/2011 the chemical loss of O3 in the polar vortex is consistent with and confirms findings reported elsewhere. More than 70% of O3 was depleted between the 425 K and 525 K isentropic surfaces, i.e. in the altitude range ~16–20 km. In contrast, during the same period in the previous winter only slightly more than 20% depletion occurred below 20 km, whereas 40% of the O3 was removed above the 575 K isentrope (~23 km. This loss above the 575 K isentrope is explained by the catalytic destruction by the NOx descending from the mesosphere. At lower altitudes O3 loss results from processing by halogen driven O3 catalytic removal cycles, activated by the large volume of PSC generated throughout this winter and spring. The mid-winter 2011 conditions, prior to the catalytic cycles being fully effective, are also investigated. Surprisingly, a significant loss of O3 with 60% is observed in mid-January 2011 below 500 K (~19 km

  4. DIETA DO MANDUBÉ, Ageneiosus ucayalensis (CASTELNAU, 1855, (OSTEICHTHYES: AUCHENIPTERIDAE DO RESERVATÓRIO DA USINA HIDRELÉTRICA COARACY NUNES, FERREIRA GOMES-AMAPÁ, BRASIL

    Júlio César Sá-Oliveira

    2014-10-01

    Full Text Available O objetivo deste trabalho foi analisar a dieta de Ageneiosus ucayalensis do reservatório da Usina Hidrelétrica Coaracy Nunes, no município de Ferreira Gomes/AP. As amostragens foram feitas bimestralmente em três estações de coleta na área do reservatório entre julho/2009 e julho/2010. As coletas foram realizadas utilizando redes de espera, organizadas em baterias com sete redes cada e diferentes distâncias entre nós. Após a captura, foi realizada a biometria dos exemplares, sendo seus estômagos retirados, fixados e conservados para análise em laboratório. A proporção sexual foi realizada no intuito de verificar se houve diferença significativa entre os sexos. Os itens alimentares do conteúdo estomacal foram agrupados em categorias amplas e analisados através dos métodos de frequência de ocorrência e volumétrico, combinados no Índice de Importância Alimentar (IAi, por período sazonal. Os resultados evidenciaram que a proporção entre os sexos foi de 1:1, com uma leve predominância de fêmeas. Quanto à alimentação, a espécie mostrou-se carnívora, com a dieta baseada principalmente em microcrustáceos, crustáceos, peixes e material não identificável. Variações sazonais na dieta não foram nítidas e, provavelmente, estão relacionadas tanto à disponibilidade das presas na área quanto à manipulação do nível da água do reservatório pelo controle de comportas. Palavras-chave: alimentação, UHE, peixes, Siluriformes, IAi. DOI: http://dx.doi.org/10.18561/2179-5746/biotaamazonia.v4n3p73-82

  5. Efeito de diferentes meios de cultura na germinação in vitro de sementes de mangabeira (Hancornia speciosa Gomes

    Kívia Soares de Oliveira

    2014-08-01

    Full Text Available A mangabeira, pertencente à família Apocynaceae, é uma espécie nativa do Cerrado e dos tabuleiros costeiros, sendo bastante conhecida pela importância social, econômica e cultural. O objetivo deste trabalho foi avaliar o efeito de diferentes meios de cultura na germinação in vitro de sementes de mangabeira, visando contribuir cientificamente para o conhecimento da espécie. Os tratamentos utilizados foram: T1 - vermiculita (+40 mL de água; T2 - vermiculita + areia (1:1 + 40 mL de água; T3 - vermiculita + areia barrada (1:1 + 40 mL de água; T4 - vermiculita + MS básico (40 ml; T5 - vermiculita + ½ MS (40 ml; T6 - areia (+40 mL de água; T7 - areia barrada (+40 mL de água; e T8 - areia + areia barrada (1:1 + 40 mL de água. Para tanto, realizou-se um experimento com oito tratamentos, incluindo oito repetições com 80 sementes por tratamento. Foram analisadas as seguintes variáveis: porcentagem de germinação, tempo médio de germinação e índice de velocidade de germinação. O delineamento experimental foi inteiramente casualizado e as médias, comparadas pelo teste de Tukey a 5% de significância. Observaram-se diferenças significativas para a porcentagem de germinação, sendo T3 estatisticamente superior, e para o IVG, com o melhor resultado, os tratamentos T1, T2 e T3. Entretanto, os valores de tempo médio de germinação não apresentaram diferença significativa. Diante dos resultados, pôde-se concluir que os tratamentos dotados de vermiculita e combinações, T1, T2 e T3, exercem influência positiva na emergência de Hancornia speciosa Gomes.

  6. Comparison of Profile Total Ozone from SBUV (v8.6) with GOME-Type and Ground-Based Total Ozone for a 16-Year Period (1996 to 2011)

    Chiou, E. W.; Bhartia, P. K.; McPeters, R. D.; Loyola, D. G.; Coldewey-Egbers, M.; Fioletov, V. E.; Van Roozendael, M.; Spurr, R.; Lerot, C.; Frith, S. M.

    2014-01-01

    This paper describes the comparison of the variability of total column ozone inferred from the three independent multi-year data records, namely, (i) Solar Backscatter Ultraviolet Instrument (SBUV) v8.6 profile total ozone, (ii) GTO (GOME-type total ozone), and (iii) ground-based total ozone data records covering the 16-year overlap period (March 1996 through June 2011). Analyses are conducted based on area-weighted zonal means for 0-30degS, 0-30degN, 50-30degS, and 30-60degN. It has been found that, on average, the differences in monthly zonal mean total ozone vary between -0.3 and 0.8% and are well within 1 %. For GTO minus SBUV, the standard deviations and ranges (maximum minus minimum) of the differences regarding monthly zonal mean total ozone vary between 0.6-0.7% and 2.8-3.8% respectively, depending on the latitude band. The corresponding standard deviations and ranges regarding the differences in monthly zonal mean anomalies show values between 0.4-0.6% and 2.2-3.5 %. The standard deviations and ranges of the differences ground-based minus SBUV regarding both monthly zonal means and anomalies are larger by a factor of 1.4-2.9 in comparison to GTO minus SBUV. The ground-based zonal means demonstrate larger scattering of monthly data compared to satellite-based records. The differences in the scattering are significantly reduced if seasonal zonal averages are analyzed. The trends of the differences GTO minus SBUV and ground-based minus SBUV are found to vary between -0.04 and 0.1%/yr (-0.1 and 0.3DU/yr). These negligibly small trends have provided strong evidence that there are no significant time-dependent differences among these multiyear total ozone data records. Analyses of the annual deviations from pre-1980 level indicate that, for the 15-year period of 1996 to 2010, all three data records show a gradual increase at 30-60degN from -5% in 1996 to -2% in 2010. In contrast, at 50-30degS and 30degS- 30degN there has been a leveling off in the 15 years after

  7. Studies of global cloud field using measurements of GOME, SCIAMACHY and GOME-2

    Lelli, Luca

    2013-01-01

    Tropospheric clouds are main players in the Earth climate system. Characterization of long-term global and regional cloud properties aims to support trace-gases retrieval, radiative budget assessment, and analysis of interactions with particles in the atmosphere. The information needed for the determination of cloud properties can be optimally obtained with satellite remote sensing systems. This is because the amount of reflected solar light depends both on macro- and micro-physical character...

  8. Harmonisation of the GOME, SCIAMACHY, and GOME-2 total ozone data records for a better understanding of long-term trends and their causes

    Chehade, Wissam

    2014-01-01

    This thesis addresses the issue of the accurate measurements of ozone distributions in the atmosphere obtained from different satellite borne atmospheric chemistry spectrometers which represent a major need and pre-requisite for determining whether the atmospheric burden of ozone depleting substances (ODS) are reduced in accordance to the Montreal Protocol, and valuable for long-term trend analysis to detect a subsequent ozone recovery. A consolidated and homogeneous long term dataset require...

  9. Quantifying Stratospheric Chlorine Chemistry by the Satellite Spectrometers GOME and SCIAMACHY

    Kühl, Sven

    2005-01-01

    Since the mid eighties of the past century, an almost complete destruction of the ozone layer above the Antarctic in springtime (and to a lesser extent also above the Arctic) is observed, which is caused by the release of atomic chlorine and bromine from anthropogenic halogen compounds. Due to the fast phase out of the production of CFCs, the increase of the stratospheric chlorine loading could be slowed down, and the recovery of the ozone layer is expected around the year 2050. However, the ...

  10. VizieR Online Data Catalog: M dwarfs activity and radial velocity (Gomes da Silva+, 2012)

    Gomes da, Silva; J.; Santos; N., C.; Bonfils; X.; Delfosse; X.; Forveille; T.; Udry; S.; Dumusque; X.; Lovis; C.

    2012-03-01

    Due to their low mass and luminosity, M dwarfs are ideal targets if one hopes to find low-mass planets similar to Earth by using the radial velocity (RV) method. However, stellar magnetic cycles could add noise or even mimic the RV signal of a long-period companion. Following our previous work that studied the correlation between activity cycles and long-term RV variations for K dwarfs we now expand that research to the lower-end of the main sequence. Our objective is to detect any correlations between long-term activity variations and the observed RV of a sample of M dwarfs. We used a sample of 27 M-dwarfs with a median observational timespan of 5.9 years. The cross-correlation function (CCF) with its parameters RV, bisector inverse slope (BIS), full-width-at-half- maximum (FWHM) and contrast have been computed from the HARPS spectrum. The activity index have been derived using the Na I D doublet. These parameters were compared with the activity level of the stars to search for correlations. We detected RV variations up to ~5m/s that we can attribute to activity cycle effects. However, only 36% of the stars with long-term activity variability appear to have their RV affected by magnetic cycles, on the typical timescale of ~6 years. Therefore, we suggest a careful analysis of activity data when searching for extrasolar planets using long-timespan RV data. (2 data files).

  11. Accelerator, superplasticiter and silica gome by wet shotcrete; Hormigon Proyectado por Via Humeda

    NONE

    2001-07-01

    This project has been carried out by Geocontrol during the period September 1997-november 2000. The main target of this project was to establish a better knowledgement about the influence of the accelerator, silica fume, steel fibres and super plasticizer on the wet shotcrete properties. This project has been developed in three phases focused in three specifical targets: I. Effect of the accelerator, superplasticizer and silica fume dosages on shotcrete strength. II. Influence of steel fibres and silica fume on shotcrete characteristics. III. Steel fibres dosages and type effect of shotcrete absorbed energy. The main conclusions obtained from this research are the following. 1. Accelerators free of alkalis have a very little influence on the shotcrete strength reduction. 2. The best results are obtained when the accelerator dosage is the lowest, with a reference of the 4% of cement weigh. 3. The superplasticizer is very important in order to reach the lowest water/cement ratio. 4. Silica fume has a strong and positive influence on shotcrete characteristics but only if the dosages is higher than 30 kg/m''3. 5. The best results with silica fume are obtained when this product is added as a separate product, instead to be missed with other additive as superplasticizer. 6. Steel fibres addition improves dramatically the shotcrete post-failure characteristics. 7. A shotcrete without steel fibres and with a strength ranged between 25 and 40 MPa absorbers 130-180 Joules and another one with a steel mesh of 150x150x6 mm absorbers 1100 Joules. 8. Steel fibres shotcrete can reach the same energy absorption that another one reinforced with wire mesh. 9. During shotcreting the steel fibres dosages has a loss of 10 to 30 % due to shotcrete rebound. This research project allows to improve the knowledgement os shotcreting technique in order to use it with more efficiency than in the past. (Author)

  12. NY_GOME_CONTOURS: New York Bight and Gulf of Maine bathymetric contours

    U.S. Geological Survey, Department of the Interior — This bathymetric shapefile contains 10 m contours for the continental shelf and 100 m beyond the 200 m shelf edge. The contours have been derived from the National...

  13. Gomes Casseres, creador de postales fotográficas en Costa Rica (1907-1920)

    Camacho Navarro, Enrique

    2015-01-01

    Durante la primera mitad del siglo XX, la United Fruit Company, aquella empresa transnacional que fue fundada en 1899 con la intención de explotar la riqueza agroexportadora dentro del Circuncaribe, elaboró cantidades considerables de propaganda, anuncios periodísticos, tarjetas postales, libros, etcétera, todas éstas ligadas a la actividad comercial y turística que ella misma practicaba entre varios de los países de la región y los Estados Unidos. El conjunto constituyó una propuesta iconogr...

  14. Crescimento inicial de mangabeira (Hancornia speciosa Gomes em diferentes meios de germinação in vitro Initial growth of mangabeira (Hancornia speciosa Gomes in different culture medium of in vitro germination

    Ana da Silva Lédo

    2007-08-01

    Full Text Available O objetivo do trabalho foi determinar as condições mais favoráveis para a germinação in vitro de sementes e o crescimento inicial de plântulas de mangabeira. Após assepsia, sementes oriundas de frutos maduros foram inoculadas em tubos de ensaio contendo os seguintes tratamentos: T1-15 mL de meio de cultura MS; T2-15 mL de meio de cultura MS + 2,0 g L-1 de carvão ativado; T3-15 mL de meio de cultura ½ MS; e T4-15 mL de meio de cultura ½ MS + 2,0 g L-1 de carvão ativado. Todos os meios de cultura foram gelificados com 0,3 g L-1 de Phytagel® e suplementados com 3,0 g L-1 de sacarose. O experimento foi instalado em delineamento inteiramente casualizado com quatro tratamentos e oito repetições, sendo cada parcela experimental composta de dez tubos de ensaio contendo uma semente cada. Não houve diferença significativa dos tratamentos para a porcentagem de germinação aos 20 dias, que variou de 95 a 100%. Quanto ao comprimento da raiz principal, observou-se que o meio de cultura constituído de ½ MS com 2,0 g L-1 de carvão ativado proporcionou maior crescimento quando comparado com os demais tratamentos. Aos 50 dias, não foi observada a formação de plântulas anormais e nem diferenças significativas do comprimento da parte aérea das plântulas. Entretanto, a diluição em 50% dos sais do meio MS associada à presença de carvão ativado induziu maior crescimento da raiz principal (8,50 cm quando comparado com meio MS, na presença (6,19 cm ou ausência (6,00 cm de carvão ativado.The objective of this study was to determine the most favorable conditions for the in vitro germination of mangaba seeds and initial development of plantlets. After asepsis, emerging seeds of mature fruits were inoculated in tubes contend the next treatments: T1-15 mL of MS culture medium; T2-15 mL of MS culture medium + 2.0 g L-1 of activated charcoal; T3-15 mL of ½ MS culture medium; and T4-15 mL of ½ MS culture medium + 2.0 g L-1 of activated charcoal. All the culture medium were gellified with 0.3 g L-1 of Phytagel® and supplemented with 3.0 g L-1 of sucrose. The statistical design was completely randomized with four treatments, eight repetitions and ten seeds by experimental unit. There was not significant difference of the treatments for the germination percentage at twenty days, which varied from 95 to 100%. The ½ MS with 2.0 g L-1 of activated charcoal promoted higher growth the main root when compared with the others treatments. After 50 days, abnormal plantlets were not observed and neither significant difference were verified among the length of the aerial part. However, the dilution in 50% of the MS culture medium associate to the presence of activated charcoal induced higher growth of the main root (8.50 cm when compared with MS culture medium in the presence (6.19 cm or absence (6.00 cm of activated charcoal.

  15. A RESPONSABILIDADE DO BRASIL PELOS CRIMES CONTRA HUMANIDADE: ANÁLISE DO JULGAMENTO «GOMES LUND E OUTROS»

    José Carlos Macedo de Pinto Ferreira Júnior

    2013-01-01

    Esta investigación tiene como objetivo analizar el juicio del caso conocido como “Guerrilla de Araguaia” y la responsabilidad internacional del Estado brasileño. Brasil había sido declarado culpable de graves violaciones de los derechos humanos, al exigir el cumplimiento de la sen- tencia la Corte Interamericana de Derechos Humanos (CIDH) y el castigo de los culpables. El caso se vuelve relevante en el escenario legal en el mundo, debido que la principal institu- ción de la justicia brasileña...

  16. A fast H2O total column density product from GOME – Validation with in-situ aircraft measurements

    Wagner, T.; J. Heland; Zöger, M.; Platt, U.

    2003-01-01

    Atmospheric water vapour is the most important greenhouse gas which is responsible for about 2/3 of the natural greenhouse effect, therefore changes in atmospheric water vapour in a changing climate (the water vapour feedback) is subject to intense debate. H2O is also involved in many important reaction cycles of atmospheric chemistry, e.g. in the production of the OH radical. Thus, long time series of global H2O data are highly required. Since 1995 ...

  17. The Impact of Global Climate Change on the Geographic Distribution and Sustainable Harvest of Hancornia speciosa Gomes (Apocynaceae) in Brazil

    Nabout, João Carlos; Magalhães, Mara Rúbia; de Amorim Gomes, Marcos Aurélio; da Cunha, Hélida Ferreira

    2016-04-01

    The global Climate change may affect biodiversity and the functioning of ecosystems by changing the appropriate locations for the development and establishment of the species. The Hancornia speciosa, popularly called Mangaba, is a plant species that has potential commercial value and contributes to rural economic activities in Brazil. The aim of this study was to evaluate the impact of global climate change on the potential geographic distribution, productivity, and value of production of H. speciosa in Brazil. We used MaxEnt to estimate the potential geographic distribution of the species in current and future (2050) climate scenarios. We obtained the productivity and value of production for 74 municipalities in Brazil. Moreover, to explain the variation the productivity and value of production, we constructed 15 models based on four variables: two ecological (ecological niche model and the presence of Unity of conservation) and two socio-economic (gross domestic product and human developed index). The models were selected using Akaike Information Criteria. Our results suggest that municipalities currently harvesting H. speciosa will have lower harvest rates in the future (mainly in northeastern Brazil). The best model to explain the productivity was ecological niche model; thus, municipalities with higher productivity are inserted in regions with higher environmental suitability (indicated by niche model). Thus, in the future, the municipalities harvesting H. speciosa will produce less because there will be less suitable habitat for H. speciosa, which in turn will affect the H. speciosa harvest and the local economy.

  18. Estimation of N-2 Fixation in four tropical leguminous trees in Sri Lanka

    DiNitrogen-fixing capacity of four species of leguminous trees of Sri Lanka (Abarema bigemina, Adenanthera bicolor, Humboldtia laurifolia and Pericopsis mooniana) by analyzing their xylem sap and by taking acetylene reducyion (AR) measurements of nodulated roots of all species, except A.bicolor which had no nodules. Based on the results of the study on P.mooniana, a method to determine the C2H2/N2 conversion factor by analysing the total NH2 compounds is being developed

  19. Measurements of O3, NO2 and BrO during the INDOEX campaign using ground based DOAS and GOME satellite data

    Ladstätter-Weißenmayer, A.; Altmeyer, H.; Bruns, M.; Richter, A; Rozanov, A.(CPPM, Aix-Marseille Université and CNRS/IN2P3, Marseille, France); V. Rozanov; Wittrock, F.; J. P. Burrows

    2007-01-01

    The INDian Ocean EXperiment (INDOEX) was an international, multi-platform field campaign to measure long-range transport of air masses from South and South-East-(SE) Asia towards the Indian Ocean. During the dry monsoon season between January and March 1999, local measurements were carried out from ground based platforms and were compared with satellite based data. The objective of this study was to characterise stratospheric and tropospheric trace gas amounts in the equa...

  20. Diferentes Composições de Substratos no Crescimento de Mudas de Genótipos de Mangabeira (Hancornia speciosa GOMES)

    Thiago Jardelino Dias; Clemilton da Silva Ferreira; Valdomiro Aurélio Barbosa de Souza; José Lucínio de Oliveira Freire; Walter Esfrain Ferreira

    2010-01-01

    O objetivo do trabalho foi avaliar efeitos de substratos no crescimento e mortalidade de mudas de mangabeira. O experimeto foi realizado em Teresina–PI, sob delineamento experimental em blocos casualizados, no esquema fatorial 6 x 10, seis composições de substratos e dez genótipos de mangabeira, com três repetições. Os substratos foram: 1. Areia (90%) + Esterco Curtido (EC – 10%) + Osmocote (1,0 g L-1); 2. Terra Vegetal (TV) + Osmocote (1,0 g L-1 ) + Supersimples (SS – 1,5 kg m-3); 3. TV (50%...

  1. Diferentes Composições de Substratos no Crescimento de Mudas de Genótipos de Mangabeira (Hancornia speciosa GOMES

    Thiago Jardelino Dias

    2010-10-01

    Full Text Available O objetivo do trabalho foi avaliar efeitos de substratos no crescimento e mortalidade de mudas de mangabeira. O experimeto foi realizado em Teresina–PI, sob delineamento experimental em blocos casualizados, no esquema fatorial 6 x 10, seis composições de substratos e dez genótipos de mangabeira, com três repetições. Os substratos foram: 1. Areia (90% + Esterco Curtido (EC – 10% + Osmocote (1,0 g L-1; 2. Terra Vegetal (TV + Osmocote (1,0 g L-1 + Supersimples (SS – 1,5 kg m-3; 3. TV (50% + Casca de Arroz Carbonizada (CAC – 50% + SS (1,5 kg m-3; 4. TV (80% + Fibra de Coco (FC – 20% + SS (1,5 kg m-3; 5. TV (75% + CAC (25% + SS (1,5 kg m-3; 6. TV (75% + FC (25% + SS (1,5 kg m-3; os genótipos (E-SPA, E-IAA, E-IAA2, E-FCPS, E-KTS, E-TBS, E-ASM, E-CFOF, E-MBN e E-IBM da coleção de germoplasma da EMEPA. Sendo seis épocas de avaliações (30, 60, 90, 120, 150 e 180 dias após transplantio. Os substratos 3 e 4 proporcionam melhor crescimento das mudas de mangabeira. O substrato 4 promove a menor mortalidade das mudas. A combinação do genótipo E-KTS x substrato 6 resulta na maior taxa de mortalidade

  2. Chemical ozone loss and ozone mini-hole event during the Arctic winter 2010/2011 as observed by SCIAMACHY and GOME-2

    Hommel, R.; Eichmann, K.-U.; J. Aschmann; Bramstedt, K.; Weber, M.; Savigny, C.; A. Richter; Rozanov, A.; Wittrock, F.; F. Khosrawi; Bauer, R.; J. P. Burrows

    2014-01-01

    Record breaking loss of ozone (O3) in the Arctic stratosphere has been reported in winter–spring 2010/2011. We examine in detail the composition and transformations occurring in the Arctic polar vortex using total column and vertical profile data products for O3, bromine oxide (BrO), nitrogen dioxide (NO2), chlorine dioxide (OClO), and polar stratospheric clouds (PSC) retrieved from measurements made by SCIAMACHY (Scanning Imaging Absorption SpectroMeter for Atmospheric CHar...

  3. Chemical composition and severe ozone loss derived from SCIAMACHY and GOME-2 observations during Arctic winter 2010/2011 in comparisons to Arctic winters in the past

    Hommel, R.; K.-U. Eichmann; J. Aschmann; Bramstedt, K.; Weber, M.; Von Savigny, C.; A. Richter; Rozanov, A.; Wittrock, F.; Bauer, R.; F. Khosrawi; J. P. Burrows

    2013-01-01

    Record breaking losses of ozone (O3) in the Arctic stratosphere have been reported in winter and spring 2011. Trace gas amounts and polar stratospheric cloud (PSC) distributions retrieved using differential optical absorption spectroscopy (DOAS) and scattering theory applied to the measurements of radiance and irradiance by satellite-born and ground-based instrumentation, document the unusual behaviour. A chemical transport model has been used to relate and compare Arctic winter-spring condit...

  4. Relatório de estágio realizado na Escola Secundária José Gomes Ferreira

    Silva, Maria Inês Vaz do Rego Pacheco

    2014-01-01

    Para a grande maioria dos professores, tornarem-se melhores profissionais passa pelo alcance máximo de sucesso pelos seus alunos (Guskey, 2002), sendo este o principal foco deste relatório. A interligação entre as quatro áreas de intervenção do estágio pedagógico, permite potencializar cada uma. A reflexão sobre o desenvolvimento pessoal e profissional enquanto professora estagiária tendo em conta um sentimento de auto-eficácia positivo (Jardim & Onofre, 2009) e uma inteligência emocial (M...

  5. “the graciouseste gome that vndir God lyffede”: a reconsideration of Sir Gawain in the Late Medieval Middle English and Middle Scots romance tradition

    Chochinov, Lauren Jessie

    2015-01-01

    In Sir Thomas Malory’s Le Morte Darthur, King Arthur’s nephew, Sir Gawain, is presented as a troublesome figure whose vengefulness hastens the collapse of Camelot. This characterization is unsurprising in the light of traditional French depictions of Gawain, but it is distinctly at odds with a rival, Anglo-Scottish tradition that depicts him rather differently as a figure of moderation, wise counsel, and courtesy. Indeed, throughout the fourteenth and fifteenth centuries, this ...

  6. SUBSTRATES FOR PRODUCTION AND GROWTH OF MANGABA (Hancornia speciosa Gomes SEEDLINGS PRODUÇÃO E CRESCIMENTO DE MUDAS DE MANGABEIRA (Hancornia speciosa Gomez EM DIFERENTES SUBSTRATOS

    Maria Eloisa Cardoso da Rosa

    2007-09-01

    Full Text Available

    Mangaba (Hancornia speciosa Gomez seedlings were transplanted eleven months after emergence to the following substrates: soil (Oxisol, soil + 33% calcined sugar-cane bagasse, and soil + 66% calcined sugar-cane bagasse, with and without lime and fertilizer. At 70, 100 and 130 days after transplanting, plants were evaluated for height and number of leaf pairs. At the end of the experiment – 130 days – roots and aerial part dry matter were weighed. The addition of 0.5 kg.m-3 of 10-10-10 fertilizer to the soil was the best treatment. Root dry matter was slightly higher than aerial part dry matter on some treatments. Roots have developed more than aerial parts. In general, substrates with pH values between 5.2 and 5.5 promote higher growth of mangaba seedlings, but those with pH between 6.0 and 6.8 cause seedling growth reduction.

    KEY-WORDS: Mangaba; native fruit trees; lime; fertilizer; substrate.

    Mudas de mangabeira (Hancornia speciosa Gomez com onze meses de idade foram submetidas a diferentes combinações de substratos: solo apenas (Latossolo Vermelho-Amarelo, solo + 33% de bagacilho de cana calcinado, e solo + 66% de bagacilho de cana calcinado, os quais receberam ou não calagem e adubação. Após a aplicação dos tratamentos, foram avaliados aos 70, 100 e 130 dias, o diâmetro basal das mudas, a altura de plantas e o número de pares de folhas, bem como o peso seco da parte aérea e da raiz, ao final do experimento. Pôde-se verificar que a adição de 0,5 kg.m-3 do adubo químico 10-10-10 ao solo foi o melhor tratamento, nas condições estudadas. Houve uma tendência de superioridade do peso seco da raiz, em relação à parte aérea, em parte dos tratamentos, evidenciando um maior desenvolvimento da raiz das mudas de mangaba, em relação à parte aérea. Valores de pH entre 5,2 a 5,5 promovem melhor desenvolvimento das mudas, enquanto valores entre 6,0 e 6,8 provocam redução no crescimento.

    PALAVRAS-CHAVE: Mangaba; frutífera nativa; calagem; fertilizante; substrato de plantio.

  7. 国美:做中国家电连锁市场的领跑者--专访国美电器广宣部经理周志坚%GOME: The Leader of Chinese Household Appliance Chain Market--an Exclusive Interview on Zhou Zhi-jian of Gome Advertisement Promotion Department Manager

    黄蕾羽

    2005-01-01

    随着2004年12月11日起,中国家电市场全面向外资开放,国外的家电连锁巨头正虎视眈眈准备全方面的一举抢滩中国市场,使得中国的家电市场战火连天,销烟弥漫.那么作为土生土长的国内家电连锁企业是如何面对这种竞争日益激烈的市场,在有限的国内市场分得一份大的蛋糕,让自已吃得饱,吃得甜,吃得香?为此,质诚中国网的记者采访了国关电器广宣部经理周志坚,了解到国美对此的战略方向.

  8. Christianne L. Gomes y Rodrigo Elizalde, Horizontes latino-americanos do lazer / Horizontes latinoamericanos del ocio, Editorial Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, Brasil, 2012, 343 p.

    Nunes Moreira, Marcina Amália

    2013-01-01

    La co-autora del libro es Post-doctora en Ciencias Sociales por la Universidad Nacional de Cuyo/Argentina, Doctora en Educación, Magister en Ciencias del Deporte y Especialista en Lazer (Ocio) por la Universidad Federal de Minas Gerais de Brasil (UFMG). El co-autor es Post-doctorando en Geografía Humana en la UFMG, Doctor y Magister en Educación con mención en Aprendizaje Transformacional por la Universidad Bolivariana de Chile (UB), Especialista en Educación Ambiental, Globalización y Desarr...

  9. Private Listing Corporation Governance Mechanism Analysis--Based on the Case Analysis of Gome%民营上市公司治理机制探析--基于国美电器的案例分析

    麻井坤

    2013-01-01

      国美控制权之争是在我国特殊市场环境下上市公司大股东与管理者之间矛盾的一个缩影,突出反映了我国民营上市公司治理机制的急需改善。在我国民营上市公司成长过程中,股东与职业经理人之间的委托代理关系受到信义的考验。本文将以国美股权之争为例,分析其存在的问题,并提出相关建议。%The separation of ownership and control is in the special market environment in China under the listing Corporation shareholders and managers a microcosm of the contradictions, reflecting the gover-nance mechanism of private listing Corporation in China in urgent need of improvement. In China, private listing Corporation in the growth process, the principal-agent relationship between shareholders and man-agers of the occupation by test of good faith. This will be the Gome’s share of the war as an example, ana-lyzes the existing problems, and puts forward the related proposal.

  10. 民营上市公司治理机制探析--基于国美电器的案例分析%Private Listing Corporation Governance Mechanism Analysis--Based on the Case Analysis of Gome

    麻井坤

    2013-01-01

      国美控制权之争是在我国特殊市场环境下上市公司大股东与管理者之间矛盾的一个缩影,突出反映了我国民营上市公司治理机制的急需改善。在我国民营上市公司成长过程中,股东与职业经理人之间的委托代理关系受到信义的考验。本文将以国美股权之争为例,分析其存在的问题,并提出相关建议。%The separation of ownership and control is in the special market environment in China under the listing Corporation shareholders and managers a microcosm of the contradictions, reflecting the gover-nance mechanism of private listing Corporation in China in urgent need of improvement. In China, private listing Corporation in the growth process, the principal-agent relationship between shareholders and man-agers of the occupation by test of good faith. This will be the Gome’s share of the war as an example, ana-lyzes the existing problems, and puts forward the related proposal.

  11. Comparação de métodos para quebra de dormência das sementes de carvoeiro – Tachigali vulgaris L.F. Gomes da Silva e H.C. Lima (Família: Fabaceae – Caesalpinioideae(Nota Científica. Comparison of methods for breaking seed dormancy of carvoeiro –Tachigali vulgaris L.F. Gomes da Silva and H.C. Lima (Family: Fabaceae – Caesalpinioideae(Scientific Note.

    Natashi Aparecida Lima PILON

    2012-06-01

    Full Text Available O cultivo de plantas nativas seja para a exploração econômica, para restauração ecológica ou qualquer outra finalidade, depende, antes de tudo, da possibilidade de propagação das espécies. A produção de mudas é o meio usual de propagação de plantas, considerando-se fundamental a germinação das sementes. Tachigali vulgaris é uma espécie arbórea de crescimento rápido e grande porte, com potencial madeireiro, cujas sementes apresentam dormência tegumentar, que dificulta a produção de mudas. Buscando encontrar a técnica mais eficaz para quebra de dormência de suas sementes, foram comparados cinco tratamentos com cinco repetições: controle, escarificação mecânica, imersão em água em temperatura ambiente (24 horas, escarificação mecânica + imersão em água em temperatura ambiente e escarificação ácida por imersão em ácido sulfúrico concentrado durante duas horas. Quase todas as sementes germinaram dentro de sete dias após a instalação do teste. As sementes sem tratamento ou imersas em água em temperatura ambiente durante 24 horas apresentaram porcentagem de germinação muito baixa, inferior a 25%. A germinação obtida para os tratamentos escarificação mecânica com lixa no 80 (84%, escarificação mecânica + imersão em água (72% e escarificação ácida (71% não diferiram significativamente entre si. Para a produção de mudas da espécie, portanto, recomenda-se a escarificação mecânica das sementes com lixa, pelo bom resultado de germinação e por dispensar o tratamento químico.The cultivation of native plants, either for economic exploitation, for ecological restoration or any other purpose, depends, above all, on the possibility of propagation of the species. The production of nursery-raised seedlings is the usual technique for propagation of tree species and seed germination is a critical step for that. The carvoeiro, Tachigali vulgaris, is a woody species of rapid growth and large size, with potential for timber, whose seeds have tegumentary dormancy, impairing the production of seedlings. Searching for the most effective technique to break dormancy of seeds, we compared five treatments with five replications each: control,mechanical scarification (sandpaper 80, immersion in water at room temperature (24 hours, mechanical scarification with sandpaper + immersion in water at room temperature, and immersion during two hours in concentrated sulfuric acid. Most seeds germinated in the first seven days after treatment application, ceasing the emergence of seedlings from this time. The germination rates of untreated seeds or simple immersion in water at room temperature were very low, less than 25%. The germination rates after mechanical scarification with sandpaper (84%, mechanical scarification with sandpaper + immersion in water (72% and acid scarification (71% did not differ significantly. Therefore, for the production of seedlings of the species, mechanical scarification of the seeds with sandpaper is recommend, which provides the tegumentary dormancy breaking and does not require chemical treatment.

  12. Home Appliance Kingdom

    JUMBO; ZHANG

    2007-01-01

    With 900 chain stores and three retail brands, Gome, China’s largest home appliance retail group, is pursuing grandiose dreams of becoming a home appliance kingdomOn November 22, 2006, Chinese home appliance retail heavyweights Beijing-based Gome Electri

  13. Ozone ProfilE Retrieval Algorithm (OPERA for nadir-looking satellite instruments in the UV–VIS

    J. C. A. van Peet

    2014-03-01

    Full Text Available For the retrieval of the vertical distribution of ozone in the atmosphere the Ozone ProfilE Retrieval Algorithm (OPERA has been further developed. The new version (1.26 of OPERA is capable of retrieving ozone profiles from UV–VIS observations of most nadir-looking satellite instruments like GOME, SCIAMACHY, OMI and GOME-2. The setup of OPERA is described and results are presented for GOME and GOME-2 observations. The retrieved ozone profiles are globally compared to ozone sondes for the years 1997 and 2008. Relative differences between GOME/GOME-2 and ozone sondes are within the limits as specified by the user requirements from the Climate Change Initiative (CCI programme of ESA (20% in the troposphere, 15% in the stratosphere. To demonstrate the performance of the algorithm under extreme circumstances, the 2009 Antarctic ozone hole season was investigated in more detail using GOME-2 ozone profiles and lidar data, which showed an unusual persistence of the vortex over the Río Gallegos observing station (51° S, 69.3° W. By applying OPERA to multiple instruments, a time series of ozone profiles from 1996 to 2013 from a single robust algorithm can be created.

  14. Ozone ProfilE Retrieval Algorithm (OPERA) for nadir-looking satellite instruments in the UV-VIS

    van Peet, J. C. A.; van der A, R. J.; Tuinder, O. N. E.; Wolfram, E.; Salvador, J.; Levelt, P. F.; Kelder, H. M.

    2014-03-01

    For the retrieval of the vertical distribution of ozone in the atmosphere the Ozone ProfilE Retrieval Algorithm (OPERA) has been further developed. The new version (1.26) of OPERA is capable of retrieving ozone profiles from UV-VIS observations of most nadir-looking satellite instruments like GOME, SCIAMACHY, OMI and GOME-2. The setup of OPERA is described and results are presented for GOME and GOME-2 observations. The retrieved ozone profiles are globally compared to ozone sondes for the years 1997 and 2008. Relative differences between GOME/GOME-2 and ozone sondes are within the limits as specified by the user requirements from the Climate Change Initiative (CCI) programme of ESA (20% in the troposphere, 15% in the stratosphere). To demonstrate the performance of the algorithm under extreme circumstances, the 2009 Antarctic ozone hole season was investigated in more detail using GOME-2 ozone profiles and lidar data, which showed an unusual persistence of the vortex over the Río Gallegos observing station (51° S, 69.3° W). By applying OPERA to multiple instruments, a time series of ozone profiles from 1996 to 2013 from a single robust algorithm can be created.

  15. Ozone ProfilE Retrieval Algorithm for nadir-looking satellite instruments in the UV-VIS

    J. C. A. van Peet

    2013-10-01

    Full Text Available For the retrieval of the vertical distribution of ozone in the atmosphere the Ozone ProfilE Retrieval Algorithm (OPERA has been further developed. The new version (1.26 of OPERA is capable of retrieving ozone profiles from UV-VIS observations of most nadir looking satellite instruments like GOME, SCIAMACHY, OMI and GOME-2. The set-up of OPERA is described and results are presented for GOME and GOME-2 observations. The retrieved ozone profiles are globally compared to ozone sondes for the year 1997 and 2008. Relative differences between GOME/GOME-2 and ozone sondes are within the limits as specified by the user requirements from the Climate Change Initiative (CCI program of ESA. To demonstrate the performance of the algorithm under extreme circumstances the 2009 Antarctic ozone hole season was investigated in more detail using GOME-2 ozone profiles and lidar data, which showed an unusual persistence of the vortex over the Río Gallegos observing station (51° S, 69.3° W. By applying OPERA to multiple instruments a timeseries of ozone profiles from 1996 to 2013 from a single robust algorithm can be created.

  16. Quantifying the Seasonal and Interannual Variability of North American Isoprene Emissions Using Satellite Observations of the Formaldehyde Column

    Palmer, Paul I.; Abbot, Dorian S.; Fu, Tzung-May; Jacob, Daniel J.; Chance, Kelly; Kurosu, Thomas P.; Guenther, Alex; Wiedinmyer, Christine; Stanton, Jenny C.; Pilling, Michael J.; Pressley, Shelley N.; Lamb, Brian; Sumner, Anne Louise

    2006-01-01

    Quantifying isoprene emissions using satellite observations of the formaldehyde (HCHO) columns is subject to errors involving the column retrieval and the assumed relationship between HCHO columns and isoprene emissions, taken here from the GEOS-CHEM chemical transport model. Here we use a 6-year (1996-2001) HCHO column data set from the Global Ozone Monitoring Experiment (GOME) satellite instrument to (1) quantify these errors, (2) evaluate GOME-derived isoprene emissions with in situ flux measurements and a process-based emission inventory (Model of Emissions of Gases and Aerosols from Nature, MEGAN), and (3) investigate the factors driving the seasonal and interannual variability of North American isoprene emissions. The error in the GOME HCHO column retrieval is estimated to be 40%. We use the Master Chemical Mechanism (MCM) to quantify the time-dependent HCHO production from isoprene, alpha- and beta-pinenes, and methylbutenol and show that only emissions of isoprene are detectable by GOME. The time-dependent HCHO yield from isoprene oxidation calculated by MCM is 20-30% larger than in GEOS-CHEM. GOME-derived isoprene fluxes track the observed seasonal variation of in situ measurements at a Michigan forest site with a -30% bias. The seasonal variation of North American isoprene emissions during 2001 inferred from GOME is similar to MEGAN, with GOME emissions typically 25% higher (lower) at the beginning (end) of the growing season. GOME and MEGAN both show a maximum over the southeastern United States, but they differ in the precise location. The observed interannual variability of this maximum is 20-30%, depending on month. The MEGAN isoprene emission dependence on surface air temperature explains 75% of the month-to-month variability in GOME-derived isoprene emissions over the southeastern United States during May-September 1996-2001.

  17. Convertible Bonds Issuing and Protection of Major Shareholders' Interests——A Case Study of Gome Electrical Appliances Holding Ltd.%可转债发行与大股东利益保护——基于国美电器股份有限公司案例分析

    徐耿彬

    2011-01-01

    When major shareholders' shareholding ratio is not at a controlling position,the issuing of convertible bonds will make major shareholders' shareholding ratio decline,and damage their interests.By the backdoor equity financing theory,the article analyzes Gome's behavior of issuing convertible bonds.It's found that the issuing of convertible bonds not only worsens the financial condition,but also dilutes the shareholding ratio of major shareholders,thus damages their interests.%当大股东的持股比例达不到控股地位时,可转债的发行将会使得大股东的持股比例出现下降,进而损害到大股东的利益。文章利用可转债发行中的后门权益融资理论对国美电器所发行可转债的行为进行分析,结果发现国美可转债的发行除了使得财务状况发生恶化外,还使得大股东的持股比例发生了稀释,由此损害了大股东的利益。

  18. Disease: H01070 [KEGG MEDICUS

    Full Text Available M, Gomes TT Laboratory evaluation on pathogenic potentialities of Vibrio furnissii. Mem Inst Oswaldo Cruz 88:593-7 (1993) ... ...15-23 (2007) PMID:8139467 (description) Magalhaes V, Castello Filho A, Magalhaes

  19. Sotsiaalministeeriumis on käimas projekt "Meeste ja naiste võrdõiguslikkus - tõhusate ja jätkusuutlike ettevõtete põhimõte ja eesmärk" / Kadi Viik ; interv. Signe Rummo

    Viik, Kadi

    2008-01-01

    Sotsiaalministeeriumi soolise võrdõiguslikkuse osakonna juhataja tutvustab aastatel 2007-2008 sotsiaalministeeriumis teostatavat Eesti-Prantsuse mestiprojekti. Kommenteerib projekti Prantsusmaa-poolne ekspert Vicki Donlevy-Gomes

  20. Clash of the Appliance Titans

    LAN XINZHEN

    2010-01-01

    @@ Even while serving out a sentence behind bars,Chinese billionaire Huang Guangyu fought for control of Gome,the appliance chain he built up in the late 1980s,but lost the high-profile war to sack current chairman,Chen Xiao.The fact that Huang remains Gome's largest shareholder has paved the way for future power struggles over the appliance giant.

  1. Total columns of H2O measured from the ground and from space at Observatoire de Haute-Provence in France (44° N)

    S. Alkasm; A. Sarkissian; Keckhut, P.; A. Pazmino; Goutail, F.; M. Pinharanda; Noël, S

    2013-01-01

    In this work, we compare vertical column density of water vapour measured at Observatoire de Haute-Provence, Southern France (5° 42' E, +43° 55' N). Data were obtained by three satellite sensors, GOME, GOME 2 and SCIAMACHY, and by two ground-based spectrometers, Elodie and SAOZ. These five instruments are able to measure total column density of water vapour in the visible and have different principles of observation. All these instruments reproduce the total column water vapour with g...

  2. Quantifying the Seasonal and Interannual Variability of North American Isoprene Emissions Using Satellite Observations of the Formaldehyde Column

    Palmer, Paul I.; Abbot, Dorian S.; Fu, Tzung-May; Jacob, Daniel J.; Chance, Kelly V.; Kurosu, Thomas Paul; GUENTHER, ALEX; Wiedinmyer, Christine; Stanton, Jenny C.; Pilling, Michael J.; Pressley, Shelley N.; Lamb, Brian; Sumner, Anna Louise

    2006-01-01

    Quantifying isoprene emissions using satellite observations of the formaldehyde (HCHO) columns is subject to errors involving the column retrieval and the assumed relationship between HCHO columns and isoprene emissions, taken here from the GEOS-CHEM chemical transport model. Here we use a 6-year (1996–2001) HCHO column data set from the Global Ozone Monitoring Experiment (GOME) satellite instrument to (1) quantify these errors, (2) evaluate GOME-derived isoprene emissions with in situ flux m...

  3. On the existence of classical solutions for stationary extended mean field games

    Gomes, Diogo A.

    2014-04-01

    In this paper we consider extended stationary mean-field games, that is mean-field games which depend on the velocity field of the players. We prove various a-priori estimates which generalize the results for quasi-variational mean-field games in Gomes et al. (2012). In addition we use adjoint method techniques to obtain higher regularity bounds. Then we establish the existence of smooth solutions under fairly general conditions by applying the continuity method. When applied to standard stationary mean-field games as in Lasry and Lions (2006), Gomes and Sanchez-Morgado (2011) or Gomes et al. (2012) this paper yields various new estimates and regularity properties not available previously. We discuss additionally several examples where the existence of classical solutions can be proved. © 2013 Elsevier Ltd. All rights reserved.

  4. Summertime weekly cycles of observed and modeled NOx and O3 concentrations as a function of land use type and ozone production sensitivity over the Continental United States

    P. Lee

    2012-01-01

    Full Text Available Simulation results from the Community Multiscale Air Quality (CMAQ model version 4.7.1 over the Conterminous United States (CONUS for August 2009 are analyzed to evaluate how satellite-derived O3 sensitivity regimes capture weekly cycles of the U.S. EPA's Air Quality System (AQS observed ground-level concentrations of ozone (O3. AQS stations are classified according to a geographically-based land use designation or an O3-NOx-VOC chemical sensitivity regime. Land use designations are derived from the Advanced Very High Resolution Radiometer (AVHRR global land cover characteristic data representing three features: urban regions, forest regions, and other regions. The O3 chemical regimes (NOx-saturated, mixed, and NOx-sensitive are inferred from low to high values of photochemical indicators based on the ratio of the HCHO to NO2 column density from the Global Ozone Monitoring Experiment 2 (GOME-2 and CMAQ. Both AQS-observed weekly cycles of NOx at measurement sites over AVHRR geographical regions and GOME-2 sensitivity regimes show high NOx on weekdays and low NOx on weekends. However, the AQS-observed O3 weekly cycle at sites over the GOME-2 NOx-saturated regime is noticeably different from that over the AVHRR urban region. Whereas the high weekend O3 anomaly is clearly shown at sites over the GOME-2 NOx-saturated regime in both AQS and CMAQ, the weekend effect is not captured at other sites over the AVHRR urban region. In addition, the weekend effect from AQS is more clearly discernible at sites above the GOME-2 NOx-saturated regime than at other sites above the CMAQ NOx-saturated regime. This study suggests that chemical classifications of GOME-2 chemical regime stations produces better results for weekly O3 cycles than either the CMAQ chemical or AVHRR geographical classifications.

  5. Improvement of OMI Ozone Profile Retrievals in the Troposphere and Lower Troposphere by the Use of the Tropopause-Based Ozone Profile Climatology

    Bak, Juseon; Liu, X.; Wei, J.; Kim, J. H.; Chance, K.; Barnet, C.

    2011-01-01

    An advance algorithm based on the optimal estimation technique has beeen developed to derive ozone profile from GOME UV radiances and have adapted it to OMI UV radiances. OMI vertical resolution : 7-11 km in the troposphere and 10-14 km in the stratosphere. Satellite ultraviolet measurements (GOME, OMI) contain little vertical information for the small scale of ozone, especially in the upper troposphere (UT) and lower stratosphere (LS) where the sharp O3 gradient across the tropopause and large ozone variability are observed. Therefore, retrievals depend greatly on the a-priori knowledge in the UTLS

  6. Ozone Profile Retrieval Algorithm (OPERA) for nadir-looking satellite instruments in the UV-VIS

    Van Peet, J.C.A.; Van der A, R.J.; Tuinder, O.N.E.; Wolfram, E.; Salvador, J.; Levelt, P.F.; Kelder, H.M.

    2014-01-01

    For the retrieval of the vertical distribution of ozone in the atmosphere the Ozone ProfilE Retrieval Algorithm (OPERA) has been further developed. The new version (1.26) of OPERA is capable of retrieving ozone profiles from UV–VIS observations of most nadir-looking satellite instruments like GOME,

  7. The "pas de deux "between remote sensing and tropospheric ozone models

    Nijenhuis, W.A.S.

    1999-01-01

    Levels of tropospheric ozone need to be assessed for scientific research of environmental problems. This can be done through use of models like the LOTOS (Long Term Ozone Simulation) model, ground level and radiosonde measurements and 1 observations by space-born sensors like GOME and SCIAMACHY. The

  8. Business in Brief

    2005-01-01

    China Raises Interest Rates on Private Mortgages;Gome Founder Looking for Successor;World Bank Three Challenges for Chinese Economic Development;Banned Dye Sudan I Found in KFC;Skyscrapers Restricted in Shanghai;Wenzhou Footwear Russia Export Dispute;Foreign Bidding for Controlling Stake of Chang Hwa Bank in Taiwan;First International Festival for Chinese Animation Industry.

  9. More than Just Hot Air: How Hairdryers and Role Models Inspire Girls in Engineering

    Kekelis, Linda; Larkin, Molly; Gomes, Lyn

    2014-01-01

    This article describes a reverse-engineering project where female students take a part a hair dryer--giving them an opportunity to see the many different kinds of engineering disciplines involved in making a hairdryer and that they work together. Mechanical Engineer, Lyn Gome, describes her experience leading a group of middle school girls through…

  10. On the thermal properties of nuclear matter with neutron excess

    The schematic model of nuclear matter proposed by Gomes, Walecka and Weisskopf which was generalized to finite temperatures including interacting Fermi particle aspects is extended here to include nuclear matter with neutron excess. The level density parameter as a function of neutron excess is calculated. Also the temperature dependence of the equilibrium Fermi momentum is calculated. (author)

  11. Maps of the “sin”: streets and subjects of the prostitution doi:10.5007/1807-1384.2010v7n2p371

    Latif Antonia Cassab

    2010-12-01

    Full Text Available Review:FÁVERI, Marlene; SILVA Janine Gomes da; PEDRO, Joana Maria (Orgs..  Prostituição em áreas urbanas. Histórias do Tempo Presente. Florianópolis, Santa Catarina: UDESC, 2010.

  12. Fungal diversity in oxygen-depleted regions of the Arabian Sea revealed by targeted environmental sequencing combined with cultivation

    Manohar, C.S.; Raghukumar, C.; Behnke, A.; Stoeck, T.

    B. (Mclaughlin DJ, McLaughlin EG & Lemke PA eds), pp. 1-36. Springer-Verlag, Berlin. Gomes NCM, Fagbola O, Costa R, Rumjanek NG, Buchner A, Mendona-Hagler L & Smalla K (2003) Dynamics of fungal communities in bulk and maize rhizosphere soil...

  13. 78 FR 58320 - National Institute on Drug Abuse; Notice of Closed Meetings

    2013-09-23

    ... HUMAN SERVICES National Institutes of Health National Institute on Drug Abuse; Notice of Closed Meetings... Committee: National Institute on Drug Abuse Special Emphasis Panel GOMED: Grand Opportunity in Medications... of Extramural Affairs, National Institute on Drug Abuse, NIH, Room 4228, MSC 9550, 6001...

  14. Kaitstud magistritööd, 1. juuni 2012

    2013-01-01

    Oma töid kaitsesid Claudio Julio Rodriguez Higuera, Davi William Ferreira Gomes, Karlina Vaivade, Mohamed Gamal Abdelmeged Elmaayergy, Sigita Tamošauskaite, Eduardo Chávez Herrera, Tyler James Bennett, Felipe Cuervo Restrepo, Julia Popova, Anastasiia Sidielnik, Thomas Mark Boyle, Mirjam Männik, Sandra Preiman, Tamara Stojanovic

  15. Transitional phases of mica crystals volcanic materials

    Melka, Karel

    Vol. 1. Madeira: Centro de ciencia e tecnologia da Madeira, 2000 - (Gomes, C.), s. 306-316 ISBN 972-98383-4-8. [Latin-American Clay Conference /1./. Funchal - Madeira (PT), 17.09.2000-22.09.2000] Institutional research plan: CEZ:AV0Z3013912 Subject RIV: DB - Geology ; Mineralogy

  16. TROPOMI and TROPI: UV/VIS/NIR/SWIR instruments

    Levelt, P.F.; Oord, G.H.J. van den; Dobber, M.; Eskes, H.; Weele, M. van; Veefkind, P.; Oss, R. van; Aben, I.; Jongma, R.T.; Landgraf, J.; Vries, J. de; Visser, H.

    2006-01-01

    TROPOMI (Tropospheric Ozone-Monitoring Instrument) is a five-channel UV-VIS-NIR-SWIR non-scanning nadir viewing imaging spectrometer that combines a wide swath (114°) with high spatial resolution (10 × 10 km 2). The instrument heritage consists of GOME on ERS-2, SCIAMACHY on Envisat and, especially,

  17. Book Review "Advances on remote laboratories and e-learning experiences"

    Jesús A. del Alamo

    2007-08-01

    Full Text Available Book Review "Advances on remote laboratories and e-learning experiences", book editors: Luís Gomes and Javier García-Zubía, University of Deusto, Spain. Reviewed by Jesús A. del Alamo, Massachusetts Institute of Technology, M.I.T.

  18. Assimilation of Satellite-Retrieved Tropospheric NO2 Columns and in-situ Observations into the CMAQ CTM Model

    Eben, Kryštof; Resler, Jaroslav; Juruš, Pavel; Krč, Pavel

    Urbino : ACCENT Secretariat, 2009 - (Burrows, J.; Borrell, P.), s. 191-195 [ACCENT/AT2 Workshop /7./. Helsinki (FI), 30.10.2008-01.11.2008] Institutional research plan: CEZ:AV0Z10300504 Keywords : tropospheric column of NO2 * satellite instruments GOME2 and OMI * CTM CMAQ * 4DVar data assimilation Subject RIV: IN - Informatics, Computer Science

  19. Combined calpain-induced downregulation of TrkB-FL and TrkB-T1 upregulation causes neuronal death in excitotoxicity and ischemia

    Díaz-Guerra, Margarita; Vidaurre, Oscar G.; Gascón, Sergio

    2012-01-01

    Electronic response to "Excitotoxicity downregulates TrkB.FL signaling and upregulates the neuroprotective truncated TrkB receptors in cultured hippocampal and striatal neurons" Gomes, et al., 32(13): 4610-4622; doi: 10.1523/JNEUROSCI.0374-12.2012

  20. Homogenization of UV-Visible NDACC spectrometers reprocessing for ozone and NO2

    Pazmino, Andrea

    2010-05-01

    SAOZ is a ground-based UV-Visible zenith-sky spectrometer deployed since 1988 at a number of NDACC (Network for the Detection of Atmospheric Composition Change) stations at all latitudes on the globe. The instrument is providing ozone and NO2 total columns at sunrise and sunset using the Differential Optical Absorption Spectroscopy (DOAS) technique in the visible spectral range. SAOZ observations have been used extensively to validate various atmospheric chemistry satellite instruments such as nadir viewing TOMS, GOME, SCIAMACHY, OMI and GOME-2. The NDACC UV-Visible working group initiated a tentative homogenization of ozone and NO2 processing of all UV-Vis zenith sky spectrometers as one of its objectives. The first recommendation is concerning the total ozone retrieval. A significant change for the SAOZ network is the use of different cross-sections (O3, NO2, H2O, O4, and Ring calculations) and different spectral window fitting range, which leads to a recalculation of the slant columns. In addition, it is recommended to use a climatological air mass factor (AMF) instead of an annual AMF usually used in standard SAOZ processing. Here we present the results of comparisons between TOMS (since 1988), GOME (since 1995), SCIAMACHY (since 2002), OMI (since 2004), GOME-2 (since 2006) and SAOZ at all latitudes - tropics, mid-latitudes and Polar Regions - in both hemispheres. In the case of ozone, the NDACC recommendations resulted in a significant improvement of the differences between ground-based SAOZ and measurements from space. Preliminary results of NO2 SAOZ columns, using climatological AMF, are also presented and compared to different satellites, such as GOME, SCIAMACHY and OMI.

  1. Validity of satellite measurements used for the monitoring of UV radiation risk on health

    F. Jégou

    2011-06-01

    Full Text Available In order to test the validity of ultraviolet index (UVI satellite products and UVI model simulations for general public information, intercomparison involving three satellite instruments (SCIAMACHY, OMI and GOME-2, the Chemistry and Transport Model, Modélisation de la Chimie Atmosphérique Grande Echelle (MOCAGE, and ground-based instruments was performed in 2008 and 2009. The intercomparison highlighted a systematic high bias of ~1 UVI in the OMI clear-sky products compared to the SCIAMACHY and TUV model clear-sky products. The OMI and GOME-2 all-sky products are close to the ground-based observations with a low 6 % positive bias, comparable to the results found during the satellite validation campaigns. This result shows that OMI and GOME-2 all-sky products are well appropriate to evaluate the UV-risk on health. The study has pointed out the difficulty to take into account either in the retrieval algorithms or in the models, the large spatial and temporal cloud modification effect on UV radiation. This factor is crucial to provide good quality UV information. OMI and GOME-2 show a realistic UV variability as a function of the cloud cover. Nevertheless these satellite products do not sufficiently take into account the radiation reflected by clouds. MOCAGE numerical forecasts show good results during periods with low cloud covers, but are actually not adequate for overcast conditions; this is why Météo-France currently uses human-expertised cloudiness (rather than direct outputs from Numerical Prediction Models together with MOCAGE clear-sky UV indices for its operational forecasts. From now on, the UV monitoring could be done using free satellite products (OMI, GOME-2 and operational forecast for general public by using modelling, as long as cloud forecasts and the parametrisation of the impact of cloudiness on UV radiation are adequate.

  2. Satellite-based detection of volcanic sulphur dioxide from recent eruptions in Central and South America

    D. Loyola

    2008-01-01

    Full Text Available Volcanic eruptions can emit large amounts of rock fragments and fine particles (ash into the atmosphere, as well as several gases, including sulphur dioxide (SO2. These ejecta and emissions are a major natural hazard, not only to the local population, but also to the infrastructure in the vicinity of volcanoes and to aviation. Here, we describe a methodology to retrieve quantitative information about volcanic SO2 plumes from satellite-borne measurements in the UV/Visible spectral range. The combination of a satellite-based SO2 detection scheme and a state-of-the-art 3D trajectory model enables us to confirm the volcanic origin of trace gas signals and to estimate the plume height and the effective emission height. This is demonstrated by case-studies for four selected volcanic eruptions in South and Central America, using the GOME, SCIAMACHY and GOME-2 instruments.

  3. Nota sobre antígeno relacionado à hepatite (HB Ag e anticorpo (HB Ab em população do território Federal do Amapá

    Hermann G. Schatzmayr

    1974-04-01

    Full Text Available 53 amostras de soro, provenientes de Ferreira Gomes, no Amapá, foram testados para antígeno HB Ag e anticorpo HB Ab, com uma positividade de 3,7% para HB Ag, sub-tipo D. Os autores acentuam a necessidade de inquéritos em populações brasileiras a fim de estabelecer os sub-tipos associados à hepatite.3,7% of 53 serum samples from healthy inhabitants of Ferreira Gomes, Amapá, were positive for HB Ag, subtype D. The authors síress the needs of surveys to deteet the prevalent types of antigens associated with viral hepatitis in different areas of Brazil.

  4. Ozone Monitoring Instrument

    de Vries, Johan

    The Ozone Monitoring Instrument is a trace gas monitoring instrument in the line of GOME (ERS-2) and Sciamachy (ENVISAT). Following these instruments, OMI provides UV-visible spectroscopy with a resolution sufficient to separate out the various absorbing trace gases (using DOAS or `Full' retrieval), but shaped as an imaging spectrometer. This means that a two dimensional detector is used where one dimension records the spectrum and the other images the swath. The scanning mechanism from the GOME and Sciamachy is not required anymore and there are considerable advantages with respect to simultaneous measurement of swath pixels, polarisation and obtainable swath width. The OMI consortium for a phase B is formed by Fokker Space & Systems and TPD in the Netherlands and VTT in Finland. In the presentation UV-visible atmospheric remote sensing will be placed in perspective and the OMI will be explaned.

  5. Retrospective drug utilization review: impact of pharmacist interventions on physician prescribing

    Angalakuditi M; Gomes J.

    2011-01-01

    Mallik Angalakuditi1, Joseph Gomes21Georgia State University, Atlanta, GA, USA; 2Baxter Health Care, Deerfield, IL, USAObjectives: To evaluate the impact of retrospective drug utilization review (RDUR), pharmacist’s interventions on physician prescribing, and the level of spillover effect on future prescriptions following the intervention.Methods: A retrospective case–control study was conducted at a pharmacy benefits management company using the available prescription dat...

  6. Association of body composition with sarcopenic obesity in elderly women

    Silva AO; Karnikowski MGO; Funghetto SS; Stival MM; Lima RM; Souza JC; Navalta JW; Prestes J

    2013-01-01

    Alessandro Oliveira Silva,1,2 Margô Gomes Oliveira Karnikowski,3 Silvana Schwerz Funghetto,3 Marina Morato Stival,3 Ricardo Moreno Lima,3 Jéssica Cardoso de Souza,1 James Wilfred Navalta,4 Jonato Prestes11Catholic University of Brasilia, Brasilia, DF, Brazil; 2Center University of Brasilia, Brasilia, DF, Brazil; 3University of Brasilia, Brasilia, DF, Brazil; 4University of Nevada, Las Vegas, NV, USAAbstract: The aim of the present study was to investigate the prevalence o...

  7. A study of the implicit secular equation for rayleigh waves in 2D orthotropy

    Červ, Jan; Plešek, Jiří

    Porto : INEGI-Instituto de Engenharia Mecanica e Gestao Industrial, 2013 - (Silva Gomes, J.; Meguid, S.), s. 551-552 ISBN 978-972-8826-27-7. [International Conference Integrity-Reliability-Failure /4./. Funchal (PT), 23.06.2013-27.06.2013] R&D Projects: GA ČR(CZ) GAP101/11/0288; GA ČR GA101/09/1630 Institutional support: RVO:61388998 Keywords : Rayleigh waves * secular equation * orthotropic materials Subject RIV: BE - Theoretical Physics

  8. Combining Individual and Global Tree-based Models in EEG Classification

    Klaschka, Jan

    Lisabon: Instituto Nacional de Estatística, 2008 - (Gomes, M.; Pinto Martins, J.; Silva, J.), s. 3786-3789 ISBN 978-972-673-992-0. [ISI 2007. Session of the International Statistical Institute /56./. Lisboa (PT), 22.08.2007-29.08.2007] R&D Projects: GA MŠk ME 701 Institutional research plan: CEZ:AV0Z10300504 Keywords : EEG spectra * classification forest * random forests * OOB estimates Subject RIV: BB - Applied Statistics, Operational Research

  9. Comparison of Saccharomyces cerevisiae populations from different appellations of origin and grape varieties by microsatellite analysis

    Pereira, Leonor; Machado, Sofia; Ramos, P; Alemão, F.; Gomes, P; Sousa, S.; Santos, Manuel A.S.; Duarte, F.L; Casal, Margarida; Schuller, Dorit Elisabeth

    2007-01-01

    One hundred ninety two grape samples were collected during the 2006 harvest season in the Vinho Verde (grape varieties: Arinto, Alvarinho, Avesso, Loureiro, Touriga Nacional) Bairrada (grape varieties: Arinto, Baga, Castelão Francês, Maria Gomes, Touriga Nacional) Alentejo (grape varieties, Aragonês, Trincadeira, Touriga Nacional), Terras do Sado (grape variety Castelão) Bucelas (grape variety Arinto) and Estremadura (grape varieties: Arinto, Aragonês, Castelão, Trincadeira, Touriga Nacional)...

  10. Design and construction of pavements and rail tracks : geotechnical aspects and processed materials

    Correia, A. Gomes; Momoya, Y.; Tatsuoka, F.

    2007-01-01

    The International Technical Committee, TC3 “Geotechnics of Pavements”, of the International Society for Soil Mechanics and Geotechnical Engineering–ISSMGE, started in 2001 under the proposal of the ISSMGE Board 2001–2005. It follows the previous activities of ETC 11 (1997–2001) during which an important dissemination work was done culminated with three important publications: “Unbound Granular Materials. Laboratory Testing, In Situ Testing and Modelling” (Gomes Correia, 2000), ...

  11. Source identification and budget analysis on elevated levels of formaldehyde within ship plumes: a photochemical/dynamic model analysis

    C. H. Song; Kim, H. S.; von Glasow, R.; Brimblecombe, P.; Kim, J; R. J. Park; Woo, J. H.

    2010-01-01

    Elevated levels of formaldehyde (HCHO) along the ship corridors have been observed by satellite sensors, such as ESA/ERS-2 GOME (Global Ozone Monitoring Experiment), and were also predicted by global 3-D chemistry-transport models. In this study, three likely sources of the elevated HCHO levels were investigated to identify the detailed sources and examine the contributions of the sources (budget) of the elevated levels of HCHO in the ship corridors using a newly-developed ship-plume pho...

  12. Source identification and budget analysis on elevated levels of formaldehyde within the ship plumes: a ship-plume photochemical/dynamic model analysis

    C. H. Song; Kim, H. S.; Glasow, R.; Brimblecombe, P.; Kim, J; R. J. Park; Woo, J. H.; Kim, Y H

    2010-01-01

    Elevated levels of formaldehyde (HCHO) along the ship corridors have been observed by satellite sensors, such as ESA/ERS-2 GOME (Global Ozone Monitoring Experiment), and were also simulated by global 3-D chemistry-transport models. In this study, three likely sources of the elevated HCHO levels in the ship plumes as well as their contributions to the elevated HCHO levels (budget) were investigated using a newly-developed ship-plume photochemical/dynamic model: (1) primary HC...

  13. Emotional state, state nutrition and body image

    Veiga-Branco, Augusta; Pereira, Filomena; Tavares, Mariline; Mendes, Paulo

    2014-01-01

    Literature exposes the relationship between body dissatisfaction and low self-esteem, depression and changes in eating behavior (Silva, 2009). Depression is strongly associated with anxiety and stress, which in turn, are directly related to changes in appetite and food preferences, reflected in the nutritional status of individuals (Gomes, 2010). To characterize the perception of body image and nutritional and emotional state of outpatients in Nutrition consultation; K...

  14. Phytochemical Analysis and Antimicrobial, Antinociceptive, and Anti-Inflammatory Activities of Two Chemotypes of Pimenta pseudocaryophyllus (Myrtaceae)

    Joelma Abadia Marciano de Paula; Maria do Rosário Rodrigues Silva; Maysa P. Costa; Danielle Guimarães Almeida Diniz; Sá, Fabyola A. S.; Suzana Ferreira Alves; Élson Alves Costa; Roberta Campos Lino; José Realino de Paula

    2012-01-01

    Preparations from Pimenta pseudocaryophyllus (Gomes) L.R. Landrum (Myrtaceae) have been widely used in Brazilian folk medicine. This study aims to evaluate the antimicrobial activity of the crude ethanol extracts, fractions, semipurified substances, and essential oils obtained from leaves of two chemotypes of P. pseudocaryophyllus and to perform the antinociceptive and anti-inflammatory screening. The ethanol extracts were purified by column chromatography and main compounds were spectrally c...

  15. MERIS albedo climatology for FRESCO+ O2 A-band cloud retrieval

    Zhou, Y.; P. Stammes; Brunner, D.; Wang, P.; Popp, C; M. Grzegorski

    2011-01-01

    A new global albedo climatology for Oxygen A-band cloud retrievals is presented. The climatology is based on MEdium Resolution Imaging Spectrometer (MERIS) Albedomap data and its favourable impact on the derivation of cloud fraction is demonstrated for the FRESCO+ (Fast Retrieval Scheme for Clouds from the Oxygen A-band) algorithm. To date, a relatively coarse resolution (1° × 1°) surface reflectance dataset from GOME (Global Ozone Monitoring Experiment) Lambert-equivalent reflectivity (LER) ...

  16. MERIS albedo climatology for FRESCO+ O2 A-band cloud retrieval

    Zhou, Y.; P. Stammes; Brunner, D.; Wang, P.; Popp, C; M. Grzegorski

    2010-01-01

    A new global albedo climatology for Oxygen A-band cloud retrievals is presented. The climatology is based on MEdium Resolution Imaging Spectrometer (MERIS) Albedomap data and its favourable impact on the derivation of cloud fraction is demonstrated for the FRESCO+ (Fast Retrieval Scheme for Clouds from the Oxygen A-band) algorithm. To date, a relatively coarse resolution (1° × 1°) surface reflectance dataset from GOME (Global Ozone Monitoring Experiment) Lambert-equivalent reflectivity (LER) ...

  17. Individual differences in manipulation: further studies of an emotional manipulation scale.

    Selfridge, Amy Louise

    2008-01-01

    Emotional manipulation is a strategy used by individuals to force the environment into compliance with their goals (St Clair, 1966). This study assessed the factor structure, validity and test-retest reliability of an emotional manipulation measure (Austin, Farrelly, Black & Moore, 2007). The scale was found to be valid when compared with a manipulation tactics scale (Buss, Gomes, Higgins & Lauterbach, 1987a) and also showed test-retest reliability. However the three factor structure discover...

  18. Adherence of older women with strength training and aerobic exercise

    Picorelli AMA; DS Pereira; Felício DC; Anjos DMC; Pereira DAG; RC Dias; Assis MG; LSM Pereira

    2014-01-01

    Alexandra Miranda Assumpção Picorelli, Daniele Sirineu Pereira, Diogo Carvalho Felício, Daniela Maria Dos Anjos, Danielle Aparecida Gomes Pereira, Rosângela Corrêa Dias, Marcella Guimarães Assis, Leani Souza Máximo Pereira Graduate Program in Rehabilitation Sciences, Department of Physical Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil Background: Participation of older people in a...

  19. Book Reviews

    Redactie KITLV

    2008-01-01

    David Scott; Conscripts of Modernity: The Tragedy of Colonial Enlightenment (Shalina Puri) Rebecca J. Scott; Degrees of Freedom: Louisiana and Cuba after Slavery (Olivia Maria Gomes da Cunha) Patrick Bellegarde-Smith (ed.); Fragments of Bone: Neo-African Religions in a New World (Dianne M. Stewart) Londa Schiebinger; Plants and Empire: Colonial Bioprospecting in the Atlantic World (J.D. La Fleur) F. Abiola Irele, Simon Gikandi (eds.);The Cambridge H...

  20. Contribuição para o conhecimento dos parasitos de peixes do litoral do Estado da Guanabara - parte II Contribution to the knowledge of the parasites of fishes in Guanabara State

    Delir Corrêa Gomes

    1972-01-01

    Full Text Available No presente trabalho os autores criam uma nova espécie para o gênero Lecithochirium Luehe, 1901, ficando no 3º grupo de distribuição de Freitas & Gomes (1971, mais se aproximando de L. manteri Freitas & Gomes, 1971, distinguindo-se principalmente por possuir saco genital aberto, vesícula ejaculadora externa ausente, vesícula seminal trilobada e ovos maiores. Apresentam Promatomus saltatrix (L. como novohospedador para Parahemiurus merus (Linton, 1910 Yamaguti, 1938 ressaltando as variações encontradas nas medidas. Para Acanthocollaritrema umbilicatum Trav., Freitas e Bührnheim, 1965, acusam a presença do gonotil, e por esta razão acham que provavelmente Acanthocollaritrematinae Trav., Freitas e bührnheim, 1965, deva pertencer à família Cryptogonimidae Ciurea, 1933. Referem ainda a presença de Bucephalopsis callicotyle Kohn, 1962, Microcotyle pomatomi Goto, 1899 (polistomata e larvas de Trypanorhyncha Diesing, 1863 (Cestoda0, em Pomatomus saltatrix (L..In the present work the authors propose a new species under the genus Lecithochirium Luehe, 1901, wich is enclosed in the third group of Freitas & Gomes distribuition (1971, nearest to L. manteri Freitas & Gomes, 1971, differing from it mainly by possessing open type sinus sac, externai ejaculatory vesicle lacking, seminal vesicle divided into 3 parts and bigger eggs. The authors present Pomatomus saltatrix (L. as a new host record for Parahemiurus merus (Linton, 1910 Yamaguti, 1938, giving the variations they found in measurements. To Acanthocollaritrema umbilicatum Trav., Freitas & Bührnheim, 1965 they add the presence of complex genital atrium and for this reason suggest that probably Acanthocollaritrematinae Trav., Freitas & Bührnheim, 1965 must be put under Cryptogonimidae Ciurea, 1933. They also refer Bucephalopsis callicotyle Kohn, 1962, Microcotyle pomatomus Goto, 1899 (Polystomata and some immature cestode under Trypanorhyncha Diesing, 1863 (Cestode, in Pomatomus

  1. Cosmological signatures of time-asymmetric gravity

    Cortês, Marina; Liddle, Andrew R; Smolin, Lee

    2016-01-01

    We develop the model proposed by Cort\\^es, Gomes & Smolin, to predict cosmological signatures of time-asymmetric extensions of general relativity they proposed recently. Within this class of models the equation of motion of chiral fermions is modified by a torsion term. This term leads to a dispersion law for neutrinos that associates a new time-varying energy with each particle. We find a new neutrino contribution to the Friedmann equation resulting from the torsion term in the Ashtekar conn...

  2. Myocardial bridging: retrospective analysis and scintigraphic testing of patients with no angiographically significant atherosclerotic coronary disease.

    Luz, A.C.; J. Silveira; P. Palma; Cyrne-Carvalho, H.; Albuquerque, A.; I. Amorim; Gomes, L.

    2006-01-01

    Rev Port Cardiol. 2006 Apr;25(4):397-406. Myocardial bridging: retrospective analysis and scintigraphic testing of patients with no angiographically significant atherosclerotic coronary disease. [Article in English, Portuguese] Luz A, Silveira J, Palma P, Carvalho HC, Albuquerque A, Amorim I, Gomes L. SourceServiço de Cardiologia, Hospital Geral de Santo António, Porto, Portugal. Abstract INTRODUCTION AND OBJECTIVE: The clinical relevance of myocardial bri...

  3. Prevention of eating disorders in female athletes

    Coelho GMO; Gomes AIS; Ribeiro BG; Soares EA

    2014-01-01

    Gabriela Morgado de Oliveira Coelho,1 Ainá Innocencio da Silva Gomes,2 Beatriz Gonçalves Ribeiro,2 Eliane de Abreu Soares11Nutrition Institute, Rio de Janeiro State University, Maracanã, Rio de Janeiro, Brazil; 2Federal University of Rio de Janeiro, Macaé Campus, Granja dos Cavaleiros, Macaé, BrazilAbstract: Eating disorders are serious mental diseases that frequently appear in female athletes. They are abnormal eating behaviors that can ...

  4. Global retrieval of marine and terrestrial chlorophyll fluorescence at its red peak using hyperspectral top of atmosphere radiance measurements: Feasibilirty study and first results.

    Wolanin, Aleksandra; Rozanov, V. V.; S. Noël; Dinter, Tilman; Vountas, M.; J. P. Burrows; Bracher, Astrid

    2015-01-01

    Chlorophyll fluorescence is directly linked to the physiology of phytoplankton or plants. Here, we present a new satellite remote sensing approach to retrieve chlorophyll fluorescence at its red peak (~ 685 nm) by using measurements from the hyperspectral instruments SCanning Imaging Absorption SpectroMeter for Atmospheric CHartographY (SCIAMACHY) and Global Ozone Monitoring Experiment-2 (GOME-2). This method, which is based on the Differential Optical Absorption Spectroscopy (DOAS) technique...

  5. The old and new therapeutic approaches to the treatment of giardiasis: Where are we?

    Gomes, Maria

    2009-01-01

    Haendel GNO Busatti1, Joseph FG Santos2, Maria A Gomes11Departmento de Parasitologia, ICB, Universidade Federal de Minas Gerais, Belo Horizonte, Brasil; 2Hospital Santa Casa de Misericórdia de Belo Horizonte, Minas Gerais, BrasilAbstract: Giardia lamblia is the causative agent of giardiasis, one of the most common parasitic infections of the human intestinal tract. This disease most frequently affects children causing abdominal pain, nausea, vomiting, acute or chronic diarrhea, and...

  6. Economic and environmental indicators of Mertolenga beef cattle and Serpentina goat farms in Montado areas

    Fernandes, Luís; Rosado, Maria; Marques, Fernando; Cachatra, António; Pais, José; Henriques, Nuno; Gomes, Patrícia; Agostinho, Fábio; Horta, Pedro

    2013-01-01

    Economic and environmental indicators of Mertolenga beef cattle and Serpentina goat farms in Montado areas L Fernandes, M Rosado, F Marques, A Cachatra, J Pais, N Henriques, P Gomes, F Agostinho and P Horta The present study is based upon technical and economic data collected, in the years 2010-2011, in several farms joining the ACBM (Mertolengos Cattle Breeders) and APCRS (Serpentina Goats Breeders) associations. It considers data sets collected at four farms of each of the ab...

  7. Pimenta pseudocaryophyllus inhibits virulence factors and promotes metabolic changes in Candida yeast

    2014-01-01

    Introduction This is the first study to examine the in vitro susceptibility and the expression of virulence factors in Candida species in the presence of Pimenta pseudocaryophyllus (Gomes) L.R. Landrum (Myrtaceae), a Brazilian plant known as paucravo. Additionally, the mechanisms of action of the crude ethanol extract and the ethyl acetate and aqueous fractions of this plant were investigated. Methods The in vitro susceptibility of Candida was tested using the broth microdilution method, wh...

  8. The Sun murrab Baltimaadesse ja Soome

    2008-01-01

    Aprillis andis ansambel Tanel Padar & The Sun Soomes, Lätis, Leedus ja Eestis üksteist kontserti. Heliplaadi "Here Gomes The Sun" lugu "Hopelessness You" on Soome raadiote tipp 300s neljakümnendal kohal, lugu "Learn the game" on Leedu FM99 raadios 33 enim mängitava loo seas, laul "One of those days" saavutas Läti raadio SWH rokkmuusika edetabelis teise koha.

  9. Solar Obliquity Induced by Planet Nine: Simple Calculation

    Lai, Dong

    2016-01-01

    Bailey et al.~(2016) and Gomes et al.~(2016) recently suggested that the 6 degree misalignment between the Sun's rotational equator and the orbital plane of the major planets may be produced by the forcing from the hypothetical Planet Nine on an inclined orbit. Here we present a simple but accurate calculation of the effect, which provides a clear description of how the Sun's spin orientation depends on the property of Planet Nine in this scenario.

  10. Identification and statistical analysis of global water vapour trends based on satellite data

    Mieruch, Sebastian

    2009-01-01

    Global water vapour total column amounts have been retrieved from spectral data provided by the Global Ozone Monitoring Experiment (GOME) flying on ERS-2, which was launched in April 1995, and the SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY) onboard ENVISAT launched in March 2002. For this purpose the Air Mass Corrected Differential Optical Absorption Spectroscopy (AMC-DOAS) approach has been used. The combination of the data from both instruments provides...

  11. Combining Individual and Global Tree-based Models in EEG Classification

    Klaschka, Jan

    Lisabon : Instituto Nacional de Estatística, 2008 - (Gomes, M.; Pinto Martins, J.; Silva, J.), s. 3786-3789 ISBN 978-972-673-992-0. [ISI 2007. Session of the International Statistical Institute /56./. Lisboa (PT), 22.08.2007-29.08.2007] R&D Projects: GA MŠk ME 701 Institutional research plan: CEZ:AV0Z10300504 Keywords : EEG spectra * classification forest * random forests * OOB estimates Subject RIV: BB - Applied Statistics, Operational Research

  12. Constraint of anthropogenic NOx emissions in China from different sectors : a new methodology using multiple satellite retrievals

    Lin, J.-T.; M. B. McElroy; Boersma, K. F.

    2010-01-01

    A new methodology is developed to constrain Chinese anthropogenic emissions of nitrogen oxides (NOx) from four major sectors (industry, power plants, mobile and residential) in July 2008. It combines tropospheric NO2 column retrievals from GOME-2 and OMI, taking advantage of their different passing time over China (~10:00 a.m. LT (local time) versus ~02:00 p.m.) and consistent retrieval algorithms. The approach is based on the difference of NOx columns at the overpass times ...

  13. Constraint of anthropogenic NOx emissions in China from different sectors: a new methodology using multiple satellite retrievals

    Boersma, K. F.; M. B. McElroy; J.-T. Lin

    2009-01-01

    A new methodology is developed to constrain Chinese anthropogenic emissions of nitrogen oxides (NOx) from four major sectors (industry, power plants, mobile and residential) in July 2008. It combines tropospheric NO2 column retrievals from GOME-2 and OMI, taking advantage of their different passing time over China (9:30 a.m. local time versus 1:30 p.m.), and explicitly accounts for diurnal variations in anthropogenic emissions of NOx as well as their tropospheric lifetime and column co...

  14. Averaging kernels for DOAS total-column satellite retrievals

    Eskes, H. J.; Boersma, K. F.

    2003-01-01

    The Differential Optical Absorption Spectroscopy (DOAS) method is used extensively to retrieve total column amounts of trace gases based on UV-visible measurements of satellite spectrometers, such as ERS-2 GOME. In practice the sensitivity of the instrument to the tracer density is strongly height dependent, especially in the troposphere. The resulting tracer profile dependence may introduce large systematic errors in the retrieved columns that are difficul...

  15. Ecomorphology and diet reflect the spatial segregation between two Siluriformes species inhabiting a stream of the Bodoquena Plateau, in Central Brazil

    Francisco Severo-Neto; Fabrício B. Teresa; Otávio Froehlich

    2015-01-01

    Pimelodella taenioptera Miranda Ribeiro, 1914 and Imparfinis schubarti (Gomes, 1956) are two of the most common fish species in Bodoquena Plateau streams, Paraguay basin. These species have benthic habits and subaquatical observations suggested that they present differentiation in their preference for mesohabitat types. Pimelodella taenioptera shows preference for slow waters, such as pools, while I. schubarti is associated to riffles. In this study we investigated if the known patterns of me...

  16. Inverse Modelling of Emissions and Their Time Profiles

    Resler, Jaroslav; Eben, Kryštof; Juruš, Pavel; Liczki, Jitka

    Chapel Hill : CMAS, 2009, s. 1-6. [Annual CMAS Conference /8./. Chapel Hill (US), 19.10.2009-21.10.2009] Institutional research plan: CEZ:AV0Z10300504 Keywords : 4DVar * data assimilation * inverse modelling * emission time profile * CMAQ adjoint * tropospheric column * NO2 * ozone * satellite instruments * GOME2 * OMI * IASI Subject RIV: IN - Informatics, Computer Science http://www.cmascenter.org/conference/2009/agenda.cfm?temp_id=99999

  17. Six years of total ozone column measurements from SCIAMACHY nadir observations

    C. Lerot

    2008-11-01

    Full Text Available Total O3 columns have been retrieved from six years of SCIAMACHY nadir UV radiance measurements using SDOAS, an adaptation of the GDOAS algorithm previously developed at BIRA-IASB for the GOME instrument. GDOAS and SDOAS have been implemented by the German Aerospace Center (DLR in the version 4 of the GOME Data Processor (GDP and in version 3 of the SCIAMACHY Ground Processor (SGP, respectively. The processors are being run at the DLR processing centre on behalf of the European Space Agency (ESA. We first focus on the description of the SDOAS algorithm with particular attention to the impact of uncertainties on the reference O3 absorption cross-sections. Second, the resulting SCIAMACHY total ozone data set is globally evaluated through large-scale comparisons with results from GOME and OMI as well as with ground-based correlative measurements. The various total ozone data sets are found to agree within 2% on average. However, a negative trend of 0.2–0.4%/year has been identified in the SCIAMACHY O3 columns; this probably originates from instrumental degradation effects that have not yet been fully characterized.

  18. Sensitivity study of SO{sub 2} AMF and a special case study about SO{sub 2} emissions from Norilsk Smelter

    Khokar, Mohammad Fahim [Institute for Environmental physics, Heidelberg (Germany)]|[Service d' Aeronomie, Universite Pierre and Marie Curie, Paris (France); Platt, Ulrich [Institute for Environmental Physics, Heidelberg (Germany); Granier, Claire; Law, Katey [Service d' Aeronomie, Universite Pierre and Marie Curie, Paris (France); Wagner, Thomas [Institute for Environmental physics, Heidelberg (Germany)]|[Max-Planck Institut for Chemistry, Mainz (Germany)

    2008-07-01

    Radiative transfer modelling is best tool to convert slant column densities into vertically integrated columns. In this Study, TRACY II model is used for SO{sub 2} AMF calculation for different scenarios. SO{sub 2} AMF exhibited high dependency towards surface albedo, SO{sub 2} vertical profile, SZA, wavelength, clouds and aerosol. Most of the non-ferrous metal ores contain sulfide and this is emitted as SO{sub 2} during the smelting process. Satellite observations of atmospheric sulfur dioxide (SO{sub 2}) emitted from heavy metal smelting industry in Siberia, Russia is presented. Global Ozone Monitoring Experiment (GOME) data for the years 1996 to 2002 is analyzed using a DOAS-based algorithm with the aim of retrieving SO{sub 2} column amounts. Besides, decreasing trends in the atmospheric SO{sub 2} observed by GOME, these point sources are still a dominant source of anthropogenic SO{sub 2} emissions in the region. Enhanced SO{sub 2} column amounts are clearly identified from GOME and SCIAMACHY observations over the Siberian region.

  19. Global observations of formaldehyde

    Wittrock, F.; Richter, A.; Heckel, A.; Tarsu, M.; Burrows, J. P.

    Formaldehyde (HCHO) indicates and supports photochemical activity in the atmosphere. Large amounts are expected to found in industrial areas and during biomass burning. HCHO is a major intermediate in the degradation of methane (and many other hydrocarbons). In the absence of heterogenous losses, essentially every methane molecule is converted to HCHO. Therefore it is found throughout the troposphere. It is destroyed via photolysis and reaction with OH. In continental boundary layers, non-methane hydrocarbons (NMHCs) emitted by biogenic and anthropogenic sources dominate over Methane also as a source of HCHO. GOME is the first instrument, that allows observations of Formaldehyde on a global scale giving the opportunity to improve our knowledge about emission fluxes of Methane and NMHCs. This study presents GOME observations of formaldehyde since launch of ERS-2 in 1995. Ground-based measurements are used to validate the GOME HCHO product. In addition time series for selected regions are shown to illustrate the general interannual and interseasonal variation of HCHO depending on the main sources.

  20. Long-term changes of tropospheric NO2 over megacities derived from multiple satellite instruments

    A. Hilboll

    2013-04-01

    Full Text Available Tropospheric NO2, a key pollutant in particular in cities, has been measured from space since the mid-1990s by the GOME, SCIAMACHY, OMI, and GOME-2 instruments. These data provide a unique global long-term dataset of tropospheric pollution. However, the observations differ in spatial resolution, local time of measurement, viewing geometry, and other details. All these factors can severely impact the retrieved NO2 columns. In this study, we present three ways to account for instrumental differences in trend analyses of the NO2 columns derived from satellite measurements, while preserving the individual instruments' spatial resolutions. For combining measurements from GOME and SCIAMACHY into one consistent time series, we develop a method to explicitly account for the instruments' difference in ground pixel size (40 × 320 km2 vs. 30 × 60 km2. This is especially important when analysing NO2 changes over small, localised sources like, e.g. megacities. The method is based on spatial averaging of the measured earthshine spectra and extraction of a spatial pattern of the resolution effect. Furthermore, two empirical corrections, which summarise all instrumental differences by including instrument-dependent offsets in a fitted trend function, are developed. These methods are applied to data from GOME and SCIAMACHY separately, to the combined time series, and to an extended dataset comprising also GOME-2 and OMI measurements. All approaches show consistent trends of tropospheric NO2 for a selection of areas on both regional and city scales, for the first time allowing consistent trend analysis of the full time series at high spatial resolution. Compared to previous studies, the longer study period leads to significantly reduced uncertainties. We show that measured tropospheric NO2 columns have been strongly increasing over China, the Middle East, and India, with values over east-central China tripling from 1996 to 2011. All parts of the developed world

  1. Temporal trends of anthropogenic SO2 emitted by non-ferrous metal smelters in Peru and Russia estimated from Satellite observations

    T. Wagner

    2008-09-01

    Full Text Available We report on satellite observations of atmospheric Sulfur Dioxide (SO2 emitted from metal smelting industries in Peru, South America and Siberia, Russia. Most of the non-ferrous metal ores are sulfidic and during the smelting process the sulfur is emitted as SO2. In addition to Norilsk, Russia, Peruvian copper smelters are among the most polluting point sources in the world. We retrieve SO2 column amounts from spectra of the Global Ozone Monitoring Experiment (GOME on the Earth Research Satellite 2 (ERS-2 for the years 1996 to 2002 using an algorithm based on differential Optical Absorption Spectroscopy (DOAS. Areas of enhanced SO2 column amounts are clearly identified on a 7-years mean map of GOME observations over the regions with La Oroya and Ilo copper smelters of Peru and Norilsk smelters of Russia. Since the instrument sensitivity is highly dependent on surface albedo, SO2 vertical profile, solar zenith angle (SZA, wavelength, clouds, and aerosol, radiative transfer modelling is used to convert the analysed slant column densities into vertical column densities. In this study, the full spherical Monte-Carlo radiative transport model TRACY-II is used for SO2 AMF calculation. GOME data is analysed in further detail by calculating time series over these regions. For the different locations, the results demonstrate both, increasing and decreasing trends in the SO2 column amounts over the time period of 1996–2002. The decreasing trend for the Ilo copper smelter is in good agreement with implemented measures for emission reductions. However, even for the cases with decreasing trends, these point sources are still a dominant source of anthropogenic SO2 emissions in their region. For the smelters in Peru, the potential influence due to SO2 emission by the nearby volcanoes is investigated and found to be negligible.

  2. Satellite-observed NO2, SO2, and HCHO Vertical Column Densities in East Asia: Recent Changes and Comparisons with Regional Model

    Kim, H. C.; Lee, P.; Kim, S.; Mok, J.; Yoo, H. L.; Bae, C.; Kim, B. U.; Lim, Y. K.; Woo, J. H.; Park, R.

    2015-12-01

    This study reports the recent changes in tropospheric NO2, SO2, and HCHO vertical column densities (VCD) in East Asia observed from multiple satellites, highlighting especially the annual trend changes of NO2 and SO2 over Beijing-Tianjin-Hebei (BTH) region of China since 2010. Tropospheric VCD data from Global Ozone Monitoring Experiment (GOME), SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY), Ozone Monitoring Instrument (OMI) and GOME-2, retrieved from the Royal Netherlands Meteorological Institute (KNMI) and OMI National Aeronautics and Space Administration (NASA) standard products, are utilized to investigate the annual trends of NO2, SO2, and HCHO VCDs from 2001 to 2015. They are also compared with simulations from Community Multi-scale Air Quality Model (CMAQ) based forecast system by the Integrated Multi-scale Air Quality System for Korea (IMAQS-K) of Ajou University. Until 2011, the changes in NO2 VCD over East Asian countries agree well with the findings of previous research, including the impact of the economic downturn during 2008-2009 and the subsequent quick recovery in China. After peaking in 2011, the NO2 VCD observations from active instruments (OMI and GOME-2) over China started to show a slower decreasing trend, mostly led by the rapid changes in the BTH region in northern China. On the other hand, SO2 started to decline earlier, from 2007, but inclined back from 2010 to 2012, and then back to declining trend since 2012. While satellite observations show dramatic recent changes, the model could not reproduce those changes mostly due to its use of fixed emission inventory. We conclude that rapid update of latest emission inventory is necessary for an accurate forecast of regional air quality in east Asia, especially for upcoming international sports events in PyeongChang (Korea), Tokyo (Japan) and Beijing (China) in 2018, 2020 and 2022, respectively.

  3. Multi-sensor satellite monitoring of ash and SO2 volcanic plume in support to aviation control

    Brenot, Hugues; Theys, Nicolas; Clarisse, Lieven; van Geffen, Jos; van Gent, Jeroen; Van Roozendael, Michel; van der A, Ronald; Hurtmans, Daniel; Coheur, Pierre-Francois; Clerbaux, Cathy; Valks, Pieter; Hedelt, Pascal; Prata, Fred; Rasson, Olivier; Sievers, Klaus; Zehner, Claus

    2014-05-01

    The 'Support to Aviation Control Service' (SACS; http://sacs.aeronomie.be) is an ESA-funded project hosted by the Belgian Institute for Space Aeronomy since 2007. The service provides near real-time (NRT) global volcanic ash and SO2 observations, as well as notifications in case of volcanic eruptions (success rate >95% for ash and SO2). SACS is based on the combined use of UV-visible (OMI, GOME-2 MetOp-A, GOME-2 MetOp-B) and infrared (AIRS, IASI MetOp-A, IASI MetOp-B) satellite instruments. The SACS service is primarily designed to support the Volcanic Ash Advisory Centers (VAACs) in their mandate to gather information on volcanic clouds and give advice to airline and air traffic control organisations. SACS also serves other users that subscribe to the service, in particular local volcano observatories, research scientists and airliner pilots. When a volcanic eruption is detected, SACS issues a warning that takes the form of a notification sent by e-mail to users. The SACS notification points to a dedicated web page where all relevant information is available and can be visualised with user-friendly tools. Information about the volcanic plume height from GOME-2 (MetOp-A and MetOp-B) are also available. The strength of a multi-sensor approach relies in the use of satellite data with different overpasses times, minimising the time-lag for detection and enhancing the reliability of such alerts. This presentation will give an overview of the SACS service, and of the different techniques used to detect volcanic plumes (ash, SO2 and plume height). It will also highlight the strengths and limitations of the service and measurements, and some perspectives.

  4. Data series of total columns of H2O measured from the ground and from space at Observatoire de Haute-Provence in France (44° N)

    Alkasm, Sulaf; Sarkissian, Alain; Keckhut, Philippe; Pazmino, Andrea; Goutail, Florence; Noel, Stephan

    2013-04-01

    Water vapour is an atmospheric constituent having a determinant effect on the climate and on the weather. It presents the two third of the greenhouse gases, and is mostly located in the troposphere. It is the key element of the hydrological cycle, conditioned by exchanges between its three phases in the atmosphere, the ocean and the continents, and also directed by the transport of energy between the surface and the atmosphere, by evaporation and condensation. However, because of its large temporal and spatial variability, the measure of this component is a demanding task. For this reason, many different techniques have been developed to estimate water vapour in the atmosphere. Also, the accuracy of the measurements changes from one instrument to another as the mode of observation, the period of observation, the condition of measurement, and the retrieval method are different between them. Note that these instruments were not specialised initially to water vapour measurements and the extraction of H2O was not the principle objective. This paper compares measurements of total vertical column density (VCD) of water vapour, i.e. the amount of water vapour in a vertical atmospheric column, obtained above Observatoire de Haute-Provence (OHP), south of France (5°42'E, +43°55'N) from five different instruments. This work compares results from two ground based and three satellite instruments: the SAOZ (système d'analyse par observation zénithale) an automated UV-VIS spectrometer; Elodie, a cross-dispersed echelle spectrograph and its 1.92 m telescope; SCIAMACHY, a scanning imaging absorption spectrometer for atmospheric cartography; GOME, a nadir scanning ultraviolet and visible spectrometer for global monitoring of atmospheric ozone; and GOME2, a second generation of GOME.

  5. Consistency Between Sun-Induced Chlorophyll Fluorescence and Gross Primary Production of Vegetation in North America

    Zhang, Yao; Xiao, Xiangming; Jin, Cui; Dong, Jinwei; Zhou, Sha; Wagle, Pradeep; Joiner, Joanna; Guanter, Luis; Zhang, Yongguang; Zhang , Geli; Qin, Yuanwei; Wang, Jie; Moore, Berrien, III

    2016-01-01

    Accurate estimation of the gross primary production (GPP) of terrestrial ecosystems is vital for a better understanding of the spatial-temporal patterns of the global carbon cycle. In this study,we estimate GPP in North America (NA) using the satellite-based Vegetation Photosynthesis Model (VPM), MODIS (Moderate Resolution Imaging Spectrometer) images at 8-day temporal and 500 meter spatial resolutions, and NCEP-NARR (National Center for Environmental Prediction-North America Regional Reanalysis) climate data. The simulated GPP (GPP (sub VPM)) agrees well with the flux tower derived GPP (GPPEC) at 39 AmeriFlux sites (155 site-years). The GPP (sub VPM) in 2010 is spatially aggregated to 0.5 by 0.5-degree grid cells and then compared with sun-induced chlorophyll fluorescence (SIF) data from Global Ozone Monitoring Instrument 2 (GOME-2), which is directly related to vegetation photosynthesis. Spatial distribution and seasonal dynamics of GPP (sub VPM) and GOME-2 SIF show good consistency. At the biome scale, GPP (sub VPM) and SIF shows strong linear relationships (R (sup 2) is greater than 0.95) and small variations in regression slopes ((4.60-5.55 grams Carbon per square meter per day) divided by (milliwatts per square meter per nanometer per square radian)). The total annual GPP (sub VPM) in NA in 2010 is approximately 13.53 petagrams Carbon per year, which accounts for approximately 11.0 percent of the global terrestrial GPP and is within the range of annual GPP estimates from six other process-based and data-driven models (11.35-22.23 petagrams Carbon per year). Among the seven models, some models did not capture the spatial pattern of GOME-2 SIF data at annual scale, especially in Midwest cropland region. The results from this study demonstrate the reliable performance of VPM at the continental scale, and the potential of SIF data being used as a benchmark to compare with GPP models.

  6. FRESCO+: an improved O2 A-band cloud retrieval algorithm for tropospheric trace gas retrievals

    M. van Roozendael

    2008-11-01

    Full Text Available The FRESCO (Fast Retrieval Scheme for Clouds from the Oxygen A-band algorithm has been used to retrieve cloud information from measurements of the O2 A-band around 760 nm by GOME, SCIAMACHY and GOME-2. The cloud parameters retrieved by FRESCO are the effective cloud fraction and cloud pressure, which are used for cloud correction in the retrieval of trace gases like O3 and NO2. To improve the cloud pressure retrieval for partly cloudy scenes, single Rayleigh scattering has been included in an improved version of the algorithm, called FRESCO+. We compared FRESCO+ and FRESCO effective cloud fractions and cloud pressures using simulated spectra and one month of GOME measured spectra. As expected, FRESCO+ gives more reliable cloud pressures over partly cloudy pixels. Simulations and comparisons with ground-based radar/lidar measurements of clouds show that the FRESCO+ cloud pressure is about the optical midlevel of the cloud. Globally averaged, the FRESCO+ cloud pressure is about 50 hPa higher than the FRESCO cloud pressure, while the FRESCO+ effective cloud fraction is about 0.01 larger. The effect of FRESCO+ cloud parameters on O3 and NO2 vertical column density (VCD retrievals is studied using SCIAMACHY data and ground-based DOAS measurements. We find that the FRESCO+ algorithm has a significant effect on tropospheric NO2 retrievals but a minor effect on total O3 retrievals. The retrieved SCIAMACHY tropospheric NO2 VCDs using FRESCO+ cloud parameters (v1.1 are lower than the tropospheric NO2VCDs which used FRESCO cloud parameters (v1.04, in particular over heavily polluted areas with low clouds. The difference between SCIAMACHY tropospheric NO2 VCDs v1.1 and ground-based MAXDOAS measurements performed in Cabauw, The Netherlands, during the DANDELIONS campaign is about −2.12×1014molec cm−2.

  7. FRESCO+: an improved O2 A-band cloud retrieval algorithm for tropospheric trace gas retrievals

    M. van Roozendael

    2008-05-01

    Full Text Available The FRESCO (Fast Retrieval Scheme for Clouds from the Oxygen A-band algorithm has been used to retrieve cloud information from measurements of the O2 A-band around 760 nm by GOME, SCIAMACHY and GOME-2. The cloud parameters retrieved by FRESCO are the effective cloud fraction and cloud pressure, which are used for cloud correction in the retrieval of trace gases like O3 and NO2. To improve the cloud pressure retrieval for partly cloudy scenes, single Rayleigh scattering has been included in an improved version of the algorithm, called FRESCO+. We compared FRESCO+ and FRESCO effective cloud fractions and cloud pressures using simulated spectra and one month of GOME measured spectra. As expected, FRESCO+ gives more reliable cloud pressures over partly cloudy pixels. Simulations and comparisons with ground-based radar/lidar measurements of clouds shows that the FRESCO+ cloud pressure is about the optical midlevel of the cloud. Globally averaged, the FRESCO+ cloud pressure is about 50 hPa higher than the FRESCO cloud pressure, while the FRESCO+ effective cloud fraction is about 0.01 larger. The effect of FRESCO+ cloud parameters on O3 and NO2 vertical column densities (VCD is studied using SCIAMACHY data and ground-based DOAS measurements. We find that the FRESCO+ algorithm has a significant effect on tropospheric NO2 retrievals but a minor effect on total O3 retrievals. The retrieved SCIAMACHY tropospheric NO2 VCDs using FRESCO+ cloud parameters (v1.1 are lower than the tropospheric NO2 VCDs which used FRESCO cloud parameters (v1.04, in particular over heavily polluted areas with low clouds. The difference between SCIAMACHY tropospheric NO2 VCDs v1.1 and ground-based MAXDOAS measurements performed in Cabauw, The Netherlands, during the DANDELIONS campaign is about −2.12×1014 molec cm−2.

  8. The Seasonal Cycle of Satellite Chlorophyll Fluorescence Observations and its Relationship to Vegetation Phenology and Ecosystem Atmosphere Carbon Exchange

    Joiner, J.; Yoshida, Y.; Vasilkov, A. P.; Schaefer, K.; Jung, M.; Guanter, L.; Zhang, Y; Garrity, S.; Middleton, E. M.; Huemmrich, K. F.; Gu, L.; Marchesini, L. Belelli

    2014-01-01

    Mapping of terrestrial chlorophyll uorescence from space has shown potentialfor providing global measurements related to gross primary productivity(GPP). In particular, space-based fluorescence may provide information onthe length of the carbon uptake period that can be of use for global carboncycle modeling. Here, we examine the seasonal cycle of photosynthesis asestimated from satellite fluorescence retrievals at wavelengths surroundingthe 740nm emission feature. These retrievals are from the Global OzoneMonitoring Experiment 2 (GOME-2) flying on the MetOp A satellite. Wecompare the fluorescence seasonal cycle with that of GPP as estimated froma diverse set of North American tower gas exchange measurements. Because the GOME-2 has a large ground footprint (40 x 80km2) as compared with that of the flux towers and requires averaging to reduce random errors, we additionally compare with seasonal cycles of upscaled GPP in the satellite averaging area surrounding the tower locations estimated from the Max Planck Institute for Biogeochemistry (MPI-BGC) machine learning algorithm. We also examine the seasonality of absorbed photosynthetically-active radiation(APAR) derived with reflectances from the MODerate-resolution Imaging Spectroradiometer (MODIS). Finally, we examine seasonal cycles of GPP as produced from an ensemble of vegetation models. Several of the data-driven models rely on satellite reflectance-based vegetation parameters to derive estimates of APAR that are used to compute GPP. For forested sites(particularly deciduous broadleaf and mixed forests), the GOME-2 fluorescence captures the spring onset and autumn shutoff of photosynthesis as delineated by the tower-based GPP estimates. In contrast, the reflectance-based indicators and many of the models tend to overestimate the length of the photosynthetically-active period for these and other biomes as has been noted previously in the literature. Satellite fluorescence measurements therefore show potential for

  9. Revisiting satellite derived tropospheric NO2 trends

    Richter, Andreas; Hilboll, Andreas; Burrows, John P.

    2015-04-01

    Nitrogen dioxide levels can be used as tracer of anthropogenic pollution as NOx, the sum of NO and NO2, is released during fossil fuel combustion. With its short atmospheric lifetime, atmospheric NO2 can be easily linked to its sources. Using its structured absorption cross section in the blue spectral region, NO2 amounts can be derived from measurements of backscattered solar radiation with the help of Differential Optical Absorption Spectroscopy measurements. Satellite retrievals of tropospheric NO2 became possible with the launch of the GOME instrument in 1995, and since then a series of instruments including SCIAMACHY, GOME-2 and OMI provide spectral data which can be used to quantify NO2 columns in the troposphere. Using these observations, spatial distributions of NO2, its sources and transport pathways as well as temporal changes have been investigated over the last years. In particular the latter have shown remarkable atmospheric developments with large reductions of NO2 levels in many industrialised countries and dramatic increases in regions with growing economies, most notably in China but also in many other countries. In this study, recent trends of satellite derived NO2 columns are evaluated using data from all available instruments with a focus on the last years. Combination of data taken from the two GOME-2 instruments and OMI improves coverage and sensitivity, and also provides important constraints on the reliability of the satellite data set. As in previous studies, large changes in NO2 columns are found in many regions, in particular over China where after two years of stagnating NO2 levels an unexpected substantial reduction is observed for 2014.

  10. Development of a harmonised multi sensor retrieval scheme for HCHO within the Quality Assurance For Essential Climate Variables (QA4ECV) project

    De Smedt, Isabelle; Richter, Andreas; Beirle, Steffen; Danckaert, Thomas; Van Roozendael, Michel; Yu, Huan; Bösch, Tim; Hilboll, Andreas; Peters, Enno; Doerner, Steffen; Wagner, Thomas; Wang, Yang; Lorente, Alba; Eskes, Henk; Van Geffen, Jos; Boersma, Folkert

    2016-04-01

    One of the main goals of the QA4ECV project is to define community best-practices for the generation of multi-decadal ECV data records from satellite instruments. QA4ECV will develop retrieval algorithms for the Land ECVs surface albedo, leaf area index (LAI), and fraction of active photosynthetic radiation (fAPAR), as well as for the Atmosphere ECV ozone and aerosol precursors nitrogen dioxide (NO2), formaldehyde (HCHO), and carbon monoxide (CO). Here we assess best practices and provide recommendations for the retrieval of HCHO. Best practices are established based on (1) a detailed intercomparison exercise between the QA4ECV partner's for each specific algorithm processing steps, (2) the feasibility of implementation, and (3) the requirement to generate consistent multi-sensor multi-decadal data records. We propose a fitting window covering the 328.5-346 nm spectral interval for the morning sensors (GOME, SCIAMACHY and GOME-2) and an extension to 328.5-359 nm for OMI and GOME-2, allowed by improved quality of the recorded spectra. A high level of consistency between group algorithms is found when the retrieval settings are carefully aligned. However, the retrieval of slant columns is highly sensitive to any change in the selected settings. The use of a mean background radiance as DOAS reference spectrum allows for a stabilization of the retrievals. A background correction based on the reference sector method is recommended for implementation in the QA4ECV HCHO algorithm as it further reduces retrieval uncertainties. HCHO AMFs using different radiative transfer codes show a good overall consistency when harmonized settings are used. As for NO2, it is proposed to use a priori HCHO profiles from the TM5 model. These are provided on a 1°x1° latitude-longitude grid.