Satellite remote sensing is very important to obtain a variety of cloud properties. However, the data quality from satellites varies with different satellite characteristics. From December 2015 to January 2016, ground...Satellite remote sensing is very important to obtain a variety of cloud properties. However, the data quality from satellites varies with different satellite characteristics. From December 2015 to January 2016, ground-based air quality index （AQI） data showed severe haze events occurred successively in eastern China, particularly in the Beijing-Tianjin-Hebei region. During those days, a red alert （the most serious level）, orange alert （the second-highest level）, and yellow alert （the third-highest level） for haze, were issued in Beijing. Cloud detection from four sensors onboard the ＇A-Train＇satellite constellation were compared for two severe haze episodes, on 21 and 30 December 2015 respectively. Results showed that the MODIS sensor onboard the Aqua satellite misclassified aerosol as cloud, while the other three sensors-AIRS onboard Aqua, the cloud profiling radar onboard CloudSat, and CALIOP onboard CALIPSO-did not observe cloud over the same location. Through the high-AQI haze region in the CALIPSO and CloudSat orbit track, MODIS marked cloud close to the surface, while the MODIS true-color image and CALIOP observed an aerosol layer over the same location, suggesting MODIS falsely observed cloud there. Over the haze region in eastern China, MODIS observed 36% on average greater cloud fraction than AIRS, suggesting haze pollution induces a greater MODIS cloud amount.展开更多
In order to obtain some aerosol properties in Tibetan Plateau atmosphere, simultaneous measurements of aerosols by use of a sunphotometer and an aureolementer were performed in the summer of 1998 in Lhasa(29.65°N...In order to obtain some aerosol properties in Tibetan Plateau atmosphere, simultaneous measurements of aerosols by use of a sunphotometer and an aureolementer were performed in the summer of 1998 in Lhasa(29.65°N, 91.13°E). Optical depth, volume size distribution and phase\|function of aerosols were obtained from the measurements. Religious activities can have an effect on optical depth in Lhasa. The daily average aerosol optical depth( λ =500 nm) is less than 0.2. The diurnal variations of aerosol optical depth are relatively small during the period of summer. The maximal value of the mode radius in the volume size distribution are about 0.4, 2.0 and 4.0μm.展开更多
The radiance lights data in 2006 from the National Oceanic and Atmospheric Administration Air Force Defense Meteorological Satellite Program/Operational Linescan System (DMSP/OLS) and authoritative energy data distrib...The radiance lights data in 2006 from the National Oceanic and Atmospheric Administration Air Force Defense Meteorological Satellite Program/Operational Linescan System (DMSP/OLS) and authoritative energy data distributed by the United State Energy Information Administration were applied to estimate the global distribution of anthropogenic heat flux.A strong linear relationship was found to exist between the anthropogenic heat flux and the DMSP/OLS radiance data.On a global scale,the average value of anthropogenic heat flux is approximately 0.03 W m 2 and 0.10 W m 2 for global land area.The results indicate that global anthropogenic heat flux was geographically concentrated and distributed,fundamentally correlating to the economical activities.The anthropogenic heat flux concentrated in the economically developed areas including East Asia,Europe,and eastern North America.The anthropogenic heat flux in the concentrated regions,including the northeastern United States,Central Europe,United Kingdom,Japan,India,and East and South China is much larger than global average level,reaching a large enough value that could affect regional climate.In the center of the concentrated area,the anthropogenic heat flux density may exceed 100 W m 2,according to the results of the model.In developing areas,including South America,Central and North China,India,East Europe,and Middle East,the anthropogenic heat flux can reach a level of more than 10 W m 2 ;however,the anthropogenic heat flux in a vast area,including Africa,Central and North Asia,and South America,is low.With the development of global economy and urban agglomerations,the effect on climate of anthropogenic heat is essential for the research of climate change.展开更多
基金supported by the National Natural Science Foundation of China[grant number 41590874]and[grant number41590875]
文摘Satellite remote sensing is very important to obtain a variety of cloud properties. However, the data quality from satellites varies with different satellite characteristics. From December 2015 to January 2016, ground-based air quality index （AQI） data showed severe haze events occurred successively in eastern China, particularly in the Beijing-Tianjin-Hebei region. During those days, a red alert （the most serious level）, orange alert （the second-highest level）, and yellow alert （the third-highest level） for haze, were issued in Beijing. Cloud detection from four sensors onboard the ＇A-Train＇satellite constellation were compared for two severe haze episodes, on 21 and 30 December 2015 respectively. Results showed that the MODIS sensor onboard the Aqua satellite misclassified aerosol as cloud, while the other three sensors-AIRS onboard Aqua, the cloud profiling radar onboard CloudSat, and CALIOP onboard CALIPSO-did not observe cloud over the same location. Through the high-AQI haze region in the CALIPSO and CloudSat orbit track, MODIS marked cloud close to the surface, while the MODIS true-color image and CALIOP observed an aerosol layer over the same location, suggesting MODIS falsely observed cloud there. Over the haze region in eastern China, MODIS observed 36% on average greater cloud fraction than AIRS, suggesting haze pollution induces a greater MODIS cloud amount.
基金TheNationalNaturalScienceFoundationofChina (No . 49775 2 75 )andTibetanAutonomousRegionMeteorologicalBureau
文摘In order to obtain some aerosol properties in Tibetan Plateau atmosphere, simultaneous measurements of aerosols by use of a sunphotometer and an aureolementer were performed in the summer of 1998 in Lhasa(29.65°N, 91.13°E). Optical depth, volume size distribution and phase\|function of aerosols were obtained from the measurements. Religious activities can have an effect on optical depth in Lhasa. The daily average aerosol optical depth( λ =500 nm) is less than 0.2. The diurnal variations of aerosol optical depth are relatively small during the period of summer. The maximal value of the mode radius in the volume size distribution are about 0.4, 2.0 and 4.0μm.
基金supported by theNational Natural Science Foundation of China(Grant Nos.40775008and41075015)the Ministry of Science and Technology of China(Grant No.2010DFA22770)the Chinese Academy of Sciences Strategic Prior Research Program(Grant No.XDA05100504)
文摘The radiance lights data in 2006 from the National Oceanic and Atmospheric Administration Air Force Defense Meteorological Satellite Program/Operational Linescan System (DMSP/OLS) and authoritative energy data distributed by the United State Energy Information Administration were applied to estimate the global distribution of anthropogenic heat flux.A strong linear relationship was found to exist between the anthropogenic heat flux and the DMSP/OLS radiance data.On a global scale,the average value of anthropogenic heat flux is approximately 0.03 W m 2 and 0.10 W m 2 for global land area.The results indicate that global anthropogenic heat flux was geographically concentrated and distributed,fundamentally correlating to the economical activities.The anthropogenic heat flux concentrated in the economically developed areas including East Asia,Europe,and eastern North America.The anthropogenic heat flux in the concentrated regions,including the northeastern United States,Central Europe,United Kingdom,Japan,India,and East and South China is much larger than global average level,reaching a large enough value that could affect regional climate.In the center of the concentrated area,the anthropogenic heat flux density may exceed 100 W m 2,according to the results of the model.In developing areas,including South America,Central and North China,India,East Europe,and Middle East,the anthropogenic heat flux can reach a level of more than 10 W m 2 ;however,the anthropogenic heat flux in a vast area,including Africa,Central and North Asia,and South America,is low.With the development of global economy and urban agglomerations,the effect on climate of anthropogenic heat is essential for the research of climate change.
