38 research outputs found
The relationship between methane transport to the atmosphere and the decay of the Kara Sea ice cover: satellite data for 2003–2019
Get PDFSatellite spectrometers operating on the outgoing long-wave IR (thermal) radiation of the Earth and placed in sunsynchronous polar orbits provide a wealth of information about Arctic methane (CH4) year-round, day and night. Their data are unique for estimating methane emissions from the warming Arctic, both for land and sea. The article analyzes concentrations of methane obtained by the AIRS spectrometer in conjunction with microwave satellite measurements of sea ice concentration. The data were filtered for cases of sufficiently high temperature contrast in the lower atmosphere. The focus is on the Kara Sea during autumn-early winter season between 2003 and January 2019. This sea underwent dramatic decline in the ice cover. This shelf zone is characterized by huge reserves of oil and natural gas (~90% methane), as well as presence of sub-seabed permafrost and methane hydrates. Seasonal cycle of atmospheric methane has a minimum in early summer and a maximum in early winter. During last 16 years both summer and winter concentrations were increasing, but with different rates. Positive summer trends over the Kara Sea and over Atlantic control area were close one to another. In winter the Kara Sea methane was growing faster than over Atlantic. The methane seasonal cycle amplitude tripled from 2003 to 2019. This phenomenon was considered in terms of growing methane flux from the sea. This high trend was induced by a fast decay of the sea ice in this area with ice concentrations dropped from 95 to 20%. If the current Arctic sea cover would decline further and open water area would grow then further increase of methane concentration over the ocean may be foreseen
Microbiological Aspects of Regulating the Carbon Monoxide Content in the Earth’s Atmosphere
No full textEvidences of accelerating the increase in the concentration of methane in the atmosphere after 2014: satellite data for the Arctic
Get PDFПроанализированы результаты спутникового зондирования с помощью европейского орбитального интерферометра IASI/MetOP-A и алгоритма обработки данных, разработанного в NOAA. Спутниковые измерения для умеренных и высоких широт Северного полушария дают рост скорости концентрации метана от 4–9 ppbv/год (частей на миллиард по объему) в 2010–2013 гг. до 12–17 ppbv/год в 2015–2016 гг. Глобальные оценки на основе приземных измерений NOAA на прибрежных станциях показывают возрастание от ~5–6 ppbv/год в 2007–2013 гг. до 9–12 ppbv/год в последние два года. Спутниковые данные позволяют анализировать концентрацию метана как над сушей, так и над Арктическими морями при отсутствии приповерхностных инверсий температуры. Результаты дистанционных измерений сравниваются с прямыми самолетными измерениями на Аляске в летне-осенний период в ходе эксперимента CARVE (Carbon in Arctic Reservoirs Vulnerability Experiment). Максимальные аномалии метана (по сравнению с районом между Скандинавией и Исландией) наблюдались в ноябре-декабре над морской поверхностью вдоль берегов Норвегии, Новой Земли, Шпицбергена и других районов Арктики. В летний период аномалии над океаном были незначительны. С годами аномалии росли: максимальная скорость отмечена для района к западу от Новой Земли (9,4±3,7) ppb/год. Над Аляской аномалия концентрации метана в летнее время, когда активны микробиологические источники, росла со скоростью (2,6±1,0) ppb/год. Местоположение максимумов аномалии вокруг Шпицбергена соответствует наблюдавшимся выходам метана с морского дна и предсказанным районам диссоциации метаногидратов. Отмеченное в данной работе увеличение скорости возрастания метана в течение последних двух лет не обязательно говорит о долгосрочной тенденции: 2015–2016 гг. характеризуются как период одного из наиболее сильных эффектов Эль-Ниньо
Spectroscopic measurements of atmospheric carbon monoxide and methane. 2: Seasonal variations and long-term trends
No full textSeasonal variation of carbon monoxide in northern Japan: Fourier transform IR measurements and source-labeled model calculations
Get PDFTropospheric carbon monoxide (CO) was measured throughout 2001 using ground-based Fourier transform IR (FTIR) spectrometers at Moshiri (44.4°N) and Rikubetsu (43.5°N) observatories in northern Japan, which are separated by 150 km. Seasonal and day-to-day variations of CO are studied using these data, and contributions from various CO sources are evaluated using three-dimensional global chemistry transport model (GEOS-CHEM) calculations. Seasonal maximum and minimum FTIR-derived tropospheric CO amounts occurred in April and September, respectively. The ratio of partial column amounts between the 0–4 and 0–12 km altitude ranges is found to be slightly greater in early spring. The GEOS-CHEM model calculations generally reproduce these observed features. Source-labeled CO model calculations suggest that the observed seasonal variation is caused by seasonal contributions from various sources, in addition to a seasonal change in chemical CO loss by OH. Changes in meteorological fields largely control the relative importance of various source contributions. The contributions from fossil fuel (FF) combustion in Asia and photochemical CO production have the greatest yearly averaged contribution at 1 km among the CO sources (31% each). The Asian FF contribution increases from winter to summer, because weak southwesterly wind in summer brings more Asian pollutants to the observation sites. The seasonal variation from photochemical CO production is small (±17% at 1 km), likely because of concurrent increases (decreases) of photochemical production and loss rates in summer (winter), with the largest contribution between August and December. The contribution from intercontinental transport of European FF combustion CO is found to be comparable to that of Asian FF sources in winter. Northwesterly wind around the Siberian high in this season brings pollutants from Europe directly to Japan, in addition to southward transport of accumulated pollution from higher latitudes. The influences are generally greater at lower altitudes, resulting in a vertical gradient in the CO profile during winter. The model underestimates total CO by 12–14% between March and June. Satellite-derived fire-count data and the relationship between FTIR-derived HCN and CO amounts are generally consistent with biomass burning influences, which could have been underestimated by the model calculations
About One Discussion in Russian Medieval Studies in the Late 20th Century
No full textThe article is devoted to the discussion between A. Gurevich and L. Batkin, who made a significant contribution to the development of “non-Soviet” medieval studies. The purpose of the study is to determine the characteristic features of the controversy between A. Gurevich and L. Batkin and its significance in the process of transformation of the epistemological field of Russian historical science. The principles of intellectual history constitute the theoretical foundation of the article. The study was carried out on the basis of comparative historical and historical genetic methods. The present work analyzes the views of A. Gurevich and L. Batkin on a number of methodological issues that were at the center of the debate between the scholars. The author concludes that the dispute under consideration raised questions about the cultural and social essence of the individual, about the implementation by the individual of his functions within social structures, and about the causes and mechanisms for changing cultural values and dominants. The interpretation of the concept of personality determined the choice of approach to the study of society. While for A. Gurevich, the personality is a product of the socio-cultural system of a particular era and the peculiarity of the personality lies in the original combination of common features of culture, L. Batkin views the personality as an individual who, being guided by general norms and regulations, lets them go through his consciousness and as if generates norms and values again. According to L. Batkin, “the conscious personality” is the beginning of overcoming stereotypes and matrices of social consciousness. In this regard, the approach of A. Gurevich was aimed at reconstructing social stereotypes and matrices that determined people’s behavior. L. Batkin analyzed outstanding literary works, which, according to the scholar, reveal change and transformation in the culture under study. A number of points made by L. Batkin during the polemic were perceived and interpreted by Yu. Bessmertnyi, A. Yurganov, A. Karavashkin, and I. Danilevskii and influenced the formation of their research agenda. The scholars agreed that medieval culture should be studied proceeding from the peculiarities of the development of the culture itself; attention should be paid to understanding the specifics of the language of culture, features of thinking and self-expression of the era under study; unique features of culture should be taken into account; it is required to use the principles of hermeneutics as a methodological basis for the interpretation of written sources
Interannual variations of the carbon monoxide tropospheric burden between 30ºN and 90ºN in 1996-2003: ground-based and satellite measurements, estimate of biomass burning emissions
Get PDFCarbon monoxide total column amounts in the atmosphere were measured in the High Northern Hemisphere (30º-90º N, HNH) between January 1996 and December 2003 using Fourier Transform Infrared high resolution spectrometers installed at the NDSC (Network for Detection of Stratospheric Change) sites. A grating spectrometer of moderate resolution was employed for the same purpose at the Zvenigorod Research Station of the Institute of Atmospheric Physics near Moscow. CO mixing ratios were measured in the air samples obtained at the ground-level stations of the CMDL (Climate Modeling and Diagnostic Laboratory, NOAA) network. Total column CO amounts were measured from space by the Terra/MOPITT instrument between March, 2000, and December, 2003 (Edwards et al., 2004). Anomalies of monthly mean CO densities (related to a quiet period of 2000 - 2001) for different sites in the HNH were in agreement. This fact confirmed a good mixing of CO in the Northern Hemisphere on the montly basis that may be expected from a 1.5-2-month-long CO life-time. The data were integrated over the HNH reservoir (0-10 km in altitude and 30º-90º N in latitude) and the CO burden anomalies (in Tg) were analysed using a box model. Two CO sinks were taken into account: i) internal chemical removal in the reaction between CO and OH, and ii) transport of CO into the southertn part of the Northern hemisphere, where CO concentrations are usually lower. OH concentarations were taken from Spivakovsky et al. (2000). The air exchange through the 30º N boundary of the reservoir was estimated using the GEOS-CHEM model with a real meteorology of 1998 (Yurganov et al., 2004). The interannual variations of the sinks were neglected; a corresponding uncertainty in the retrieved source anomaly was estimated to be 20-30%. Since 1996 four years have been found to experience high CO emission of similar magnitude (1996, 1998, 2002, and 2003). During four years (1997, 1999, 2000, and 2001) the emissions were relatively low. Seasonal patterns of the emissions in active years were similar, maxima occured in July-August. However, in 2003 emissions in June-July were higher than in August. These semi-hemisphere averaged emission rates correlate with Siberian forest fire counts detected at night time by the ATSR radiometer of the ERS-2 satellite (R2 =0.51). The early peak of 2003 may be attributed to forest fires in Baikal region, Siberia. An inclusion of fire counts for other areas (Europe, North America) only worsen the correlation; this implies a decisive role of the Siberian fires for polluting the Northern Hemisphere troposphere (cf., Kasischke et al., 2005). It was estimated that the boreal forest fires during active years emit 30-60 Tg CO per month in July-August and 150-200 Tg annually. These emissions may be compared to industrial and transport pollution in the Northern Hemisphere estimated by Kasischke et al. (2005) as 290 Tg CO annually (i.e., 25 Tg monthly)
Связь между переносом метана в атмосферу и разрушением ледяного покрова Карского моря: спутниковые данные за 2003–2019 гг.
Get PDFSatellite spectrometers operating on the outgoing long-wave IR (thermal) radiation of the Earth and placed in sunsynchronous polar orbits provide a wealth of information about Arctic methane (CH4) year-round, day and night. Their data are unique for estimating methane emissions from the warming Arctic, both for land and sea. The article analyzes concentrations of methane obtained by the AIRS spectrometer in conjunction with microwave satellite measurements of sea ice concentration. The data were filtered for cases of sufficiently high temperature contrast in the lower atmosphere. The focus is on the Kara Sea during autumn-early winter season between 2003 and January 2019. This sea underwent dramatic decline in the ice cover. This shelf zone is characterized by huge reserves of oil and natural gas (~90% methane), as well as presence of sub-seabed permafrost and methane hydrates. Seasonal cycle of atmospheric methane has a minimum in early summer and a maximum in early winter. During last 16 years both summer and winter concentrations were increasing, but with different rates. Positive summer trends over the Kara Sea and over Atlantic control area were close one to another. In winter the Kara Sea methane was growing faster than over Atlantic. The methane seasonal cycle amplitude tripled from 2003 to 2019. This phenomenon was considered in terms of growing methane flux from the sea. This high trend was induced by a fast decay of the sea ice in this area with ice concentrations dropped from 95 to 20%. If the current Arctic sea cover would decline further and open water area would grow then further increase of methane concentration over the ocean may be foreseen.Проанализированы ИК спутниковые данные о концентрации метана в слое атмосферы 0–4 км над Карским и Баренцевым морями в сравнении с микроволновыми спутниковыми измерениями ледяного покрова Карского моря. За последние 16 лет амплитуда сезонных вариаций метана над северной частью Карского моря выросла в 3 раза, а площадь поверхности того же района, свободная от льда, увеличилась в 4 раза. Сделан вывод о значительной роли ледяного покрова в экранировании потока метана в атмосферу
Satellite Ocean Aerosol Retrieval (SOAR) Algorithm Extension to S-NPP VIIRS as Part of the “Deep Blue” Aerosol Project
No full textThe Suomi National Polar-Orbiting Partnership (S-NPP) satellite, launched in late 2011, carries the Visible Infrared Imaging Radiometer Suite (VIIRS) and several other instruments. VIIRS has similar characteristics to prior satellite sensors used for aerosol optical depth (AOD) retrieval, allowing the continuation of space-based aerosol data records. The Deep Blue algorithm has previously been applied to retrieve AOD from Sea-viewing Wide Field-of-view Sensor (SeaWiFS) and Moderate Resolution Imaging Spectroradiometer (MODIS) measurements over land. The SeaWiFS Deep Blue data set also included a SeaWiFS Ocean Aerosol Retrieval (SOAR) algorithm to cover water surfaces. As part of NASA's VIIRS data processing, Deep Blue is being applied to VIIRS data over land, and SOAR has been adapted from SeaWiFS to VIIRS for use over water surfaces. This study describes SOAR as applied in version 1 of NASA's S-NPP VIIRS Deep Blue data product suite. Several advances have been made since the SeaWiFS application, as well as changes to make use of the broader spectral range of VIIRS. A preliminary validation against Maritime Aerosol Network (MAN) measurements suggests a typical uncertainty on retrieved 550 nm AOD of order ±(0.03+10%), comparable to existing SeaWiFS/MODIS aerosol data products. Retrieved Ångström exponent and fine-mode AOD fraction are also well correlated with MAN data, with small biases and uncertainty similar to or better than SeaWiFS/MODIS products.Further information about Deep Blue is available at https://deepblue.gsfc.nasa.gov. This research was funded under the Suomi NPP program. The MAN cruise PIs (A. Baker, S. Bilanger, R. Brewin, S. Broccardo, Y. Courcoux, P. Disterhoft, F. Dulac, R. Dunn, H. Evangelista, H. Findlay, R. Frouin, J. I. Goes, M. Harvey, M. Heller, B. N. Holben, L. Istomina, E. Joseph, P. Kermen, S. Kinne, I. Koren, N. Lagrosas, W. Landing, E. Lewis, H. S. Lim, E. Lobecker, A. Mannino, L. McKenna, N. Nalli, N. Nelson, M. Ondrusek, N. Pahlevan, P. Quinn, V. Radionov, J. S. Reid, C. Roman, J. Sciare, A. Skarke, V. Slabakova, T. Smyth, D. Sowers, M. Tzortziou, G. Stenchikov, L. Yurganov, G. Zibordi, Yanto, and T. Zielinski) are thanked for the creation and stewardship of the Sun photometer data records. AERONET and MAN data are available from https//aeronet.gsfc.nasa.gov. The GEOS-5 data used in this study have been provided by the Global Modeling and Assimilation Office (GMAO) at NASA Goddard Space Flight Center (https://gmao.gsfc.nasa.gov). NOAA VIIRS aerosol data were obtained from https://www.star.nesdis.noaa.gov/smcd/emb/viirs_aerosol. D. Antoine (Curtin), B. A. Franz (NASA GSFC), Z. Lee (University of Massachusetts Boston), and A. Vasilkov (SSAI) are thanked for useful discussions about the current status of measurements of the optical properties of seawater and bidirectional aspects of remote sensing reflectance and R. Spurr (RT Solutions) for additional development of the VLIDORT RT code and interface. Data processing was facilitated by use of the GNU Parallel utility by Tange (2011). The Atmospheres SIPS at the University of Wisconsin (particularly S. Dutcher) are acknowledged for data hosting and provision and assistance with computational resources. Prior to the public release of the VIIRS Deep Blue aerosol products, example demonstration data are available from the authors upon request. Three anonymous reviewers are thanked for their comments, which helped to improve the clarity of this manuscript and spurred the inclusion of some additional analyses.https://onlinelibrary.wiley.com/doi/abs/10.1002/2017JD02741
Spectroscopic measurements of atmospheric carbon monoxide and methane. 1: latitudinal distribution
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