A method was developed for assessing soil water content W (as basic indicator of water availability), evapotranspiration Ev, and other water and heat regime (WHR) elements of agricultural regions during vegetation season (VS).The base of the method is the physicalmathematical model of land surface-atmosphere water and heat exchange adapted to satellitederived estimates of vegetation and meteorological characteristics (VMC).These estimates used as model parameters and input variables were obtained by thematic processing data from radiometers-scanners AVHRR/NOAA, SEVIRI/Meteosat-10, -11, -8, and MSU-MR/Meteor-M No. 2 in the visible and IR ranges.Soil surface moisture (SSM) estimates used to calculate W were produced from measurements of scatterometer ASCAT/MetOp in the microwave range.The case study were carried out for forest-steppe territory of 2 27 300 km 2 located in the Black Earth Region of European Russia and for arid steppe territory of the Saratov and Volgograd Trans-Volga region of 66 600 km 2 for VS of 2016-2018.The main results of the study are: procedures to assimilate satellite-derived VMC estimates in the model were developed; the possibilities to use ASCAT-derived SSM estimates for calculating W were confirmed; W, Ev and other WHR characteristic estimates were obtained for the named VS as distributions over the area under study.
Представлены оценки характеристик водного и теплового режимов территории части Цент ральноЧернозёмного региона, преимущественно занятой посевами сельскохозяйственных культур, для сезонов вегетации 2016-2017 гг.Данные оценки были получены с помощью мо дели вертикального влаго и теплообмена поверхности суши с атмосферой LSM (Land Surface Model) при использовании спутниковой информации о состоянии подстилающей поверх ности и метеорологических условиях.Эта информация была представлена данными изме рений радиометров AVHRR (ИСЗ NOAA), МСУМР (ИСЗ «МетеорМ» № 2), SEVIRI (ИСЗ Meteosat10, 11, 8).В число рассчитываемых с помощью модели характеристик входят вла гозапасы почвы, суммарное испарение, вертикальные тепловые потоки, температура подсти лающей поверхности, влажность и температура почвы на разных глубинах.В рамках данного подхода для исследуемой территории были тестированы методики использования в модели оценок метеорологических характеристик (осадков, температуры поверхности растительного покрова и почвы, эффективной температуры подстилающей поверхности) и характеристик растительности (вегетационного индекса NDVI, проективного покрытия растительностью B, листового индекса LAI и др.), построенных по данным новых спутников (Meteosat11, 8).Проведено сравнение с фактическими значениями величин влагосодержания почвы W и сум марного испарения Ev, рассчитанных с помощью модели, в их динамике за сезон вегетации при различных вариантах оценки характеристик растительности и метеорологических харак теристик, построенных по данным измерений всех названных сенсоров.Погрешность оцен ки оказалась в пределах 15 % для W и 25 % для Ev.Показана возможность использования при моделировании оценок влажности поверхности почвы, полученных по данным измерений скаттерометра ASCAT/MetOp в СВЧдиапазоне, для выбора начальных условий при расчётах влагозапасов почвы и для расчёта испарения с поверхности почвы Ev g , являющегося одной из характеристик водного режима территории.Рассчитанные значения Ev g использовались непо средственно при расчёте влагосодержания почвы, а также
Представлены оценки характеристик водного и теплового режимов участков территории Саратовского и Волгоградского Заволжья, занятых посевами сельскохозяйственных культур, для вегетационного сезона 2012 г. Оценки получены при помощи моделей вертикального влаго- и теплообмена поверхности суши с атмосферой SVAT и SWAP и модели SEBS с использованием спутниковых данных о состоянии подстилающей поверхности и метеорологических условиях, а также аддитивной модели водоудерживания для текстурных почв.
The method has been developed to evaluate water and heat balance components for vegetation covered area of regional scale based on the refined physical-mathematical model of vertical water and heat exchange between land surface and atmosphere (Land Surface Model, LSM) for vegetation season adapted to satellite information on land surface and meteorological conditions. The LSM is accommodated for utilizing satellite-derived estimates of vegetation and meteorological characteristics as model parameters and input variables. Estimates of these characteristics presented as distributions of their values over the study area have been obtained from AVHRR/NOAA, MODIS/EOS Terra and Aqua, SEVIRI/Meteosat-9, -10 data. To build such estimates methods and technologies have been developed and refined using results of thematic processing measurement data from these sensors. Among them the original Multi Threshold Method (MTM) has been developed and tested to calculate daily precipitation sums using rainfall intensity estimates retrieved from AVHRR and SEVIRI data with subsequent replacement of ground-measured rainfall amounts by these daily rainfalls. All technologies have been adapted to the study area with square of 227300 km 2 being the part of the Central Black Earth Region of European Russia. Developed earlier procedures of utilizing satellitederived estimates of vegetation and meteorological characteristics (including precipitation) in the model have been refined and verified. Final result of modeling is the fields of soil water content, evapotranspiration and other water and heat balance components of the region under study for years 2012–2014 vegetation seasons.
Представлены результаты использования оценок характеристик растительности и метео-
The method of the AVHRR-3 (NOAA) radiometer measurement data subject processing is produced for the retrieval of underlying surface temperature and several vegetation characteristics under cloud-free conditions. A technology for deriving the values of these parameters from the MODIS (EOS/Terra and Aqua) radiometer data is developed. The estimation of the temperature and vegetation characteristics is carried out for the Seim River basin (Kursk region) with the catchment area of 7460 km 2 for 2003–2005 vegetation seasons. Practical coincidence of estimations of AVHRR- and MODIS-derived temperatures, as well as the coincidence with ground observation results, is revealed. Statistics of these estimation errors is analyzed. Satellite-derived estimations of land surface temperature (LST) and vegetation characteristics are used for the calibration and verification of the developed model of the vertical heat and water transfer in the soil-vegetation-atmosphere system (SVAT). The model is intended for calculations of evapotranspiration, soil water and heat content, latent and sensible heat fluxes, and other water and heat balance components. The abilities to compute these parameters using the satellite estimations of the leaf area index and projective vegetation cover fraction as the model parameters and LST satellite estimations as the model input variable are investigated.
A complex method for analysis of measurement data of the AVHRR radiometer of the NOAA satellite is presented, which allows detecting clouds, classifying their types, detecting precipitation zones, and estimating cloud and precipitation parameters in the daytime the year round in the midlatitudes. Tuning and testing of the method (threshold algorithms of classification) are carried out on the synchronous satellite and surface meteorological and radar data archive for central European Russia in 1998–2006. As a result of validation, characteristics are presented of reliability of satellite estimates of cloud amount, top height, maximum liquid water content in the cloud layer, and precipitation rate.
