Ultraviolet （UV） radiation has a significant influence on marine biological processes and primary productivity; however, the existing ocean color satellite sensors seldom contain UV bands. A look-up table of wavelen...Ultraviolet （UV） radiation has a significant influence on marine biological processes and primary productivity; however, the existing ocean color satellite sensors seldom contain UV bands. A look-up table of wavelength- integrated UV irradiance （280-400 nm） on the sea surface is established using the coupled ocean atmosphere radiative transfer （COART） model. On the basis of the look-up table, the distributions of the UV irradiance at middle and low latitudes are inversed by using the satellite-derived atmospheric products from the Aqua satellite, including aerosol optical thickness at 550 nm, ozone content, liquid water path, and the total precipitable water. The validation results show that the mean relative difference of the 10 d rolling averaged UV irradiance between the satellite retrieval and field observations is 8.20% at the time of satellite passing and 13.95% for the daily dose of UV. The monthly-averaged UV irradiance and daily dose of UV retrieved by satellite data show a good correlation with the in situ data, with mean relative differences of 6.87% and 8.43%, respectively. The sensitivity analysis of satellite inputs is conducted. The liquid water path representing the condition of cloud has the highest effect on the retrieval of the UV irradiance, while ozone and aerosol have relatively lesser effect. The influence of the total precipitable water is not significant. On the basis of the satellite-derived UV irradiance on the sea surface, a preliminary simple estimation of ultraviolet radiation＇s effects on the global marine primary productivity is presented, and the results reveal that ultraviolet radiation has a non-negligible effect on the estimation of the marine primary productivity.展开更多
Seabirds are good candidates as ecological indicators, especially in under-studied ecosystems since they provide insights into marine ecosystem processes and functions at various trophic levels. Our review discusses s...Seabirds are good candidates as ecological indicators, especially in under-studied ecosystems since they provide insights into marine ecosystem processes and functions at various trophic levels. Our review discusses salient points on the present status of seabirds in the Bay of Bengal Large Marine Ecosystem;despite overall low seabird numbers and biomass, this region harbors 9 species of terns, one of the most threatened bird group worldwide, which are known to breed in various marine habitats of Andaman and Nicobar islands, in addition to the coastal areas of mainland. Further, we elaborate on employing seabirds as potential indicators of this ecosystem and how they outscore other taxa in this aspect. Finally, we argue that it is essentially to fill the gaps in our knowledge about the BOBLME, mainly about the interplay between seabirds, climate change and fisheries.展开更多
基金The Public Science and Technology Research Funds Projects for Ocean Research of China under contract No.201505003the National Basic Research Program(973 Program)of China under contract No.2015CB954002the National Natural Science Foundation of China under contract Nos 41476155,41322039,41271378 and 41206168
文摘Ultraviolet （UV） radiation has a significant influence on marine biological processes and primary productivity; however, the existing ocean color satellite sensors seldom contain UV bands. A look-up table of wavelength- integrated UV irradiance （280-400 nm） on the sea surface is established using the coupled ocean atmosphere radiative transfer （COART） model. On the basis of the look-up table, the distributions of the UV irradiance at middle and low latitudes are inversed by using the satellite-derived atmospheric products from the Aqua satellite, including aerosol optical thickness at 550 nm, ozone content, liquid water path, and the total precipitable water. The validation results show that the mean relative difference of the 10 d rolling averaged UV irradiance between the satellite retrieval and field observations is 8.20% at the time of satellite passing and 13.95% for the daily dose of UV. The monthly-averaged UV irradiance and daily dose of UV retrieved by satellite data show a good correlation with the in situ data, with mean relative differences of 6.87% and 8.43%, respectively. The sensitivity analysis of satellite inputs is conducted. The liquid water path representing the condition of cloud has the highest effect on the retrieval of the UV irradiance, while ozone and aerosol have relatively lesser effect. The influence of the total precipitable water is not significant. On the basis of the satellite-derived UV irradiance on the sea surface, a preliminary simple estimation of ultraviolet radiation＇s effects on the global marine primary productivity is presented, and the results reveal that ultraviolet radiation has a non-negligible effect on the estimation of the marine primary productivity.
文摘Seabirds are good candidates as ecological indicators, especially in under-studied ecosystems since they provide insights into marine ecosystem processes and functions at various trophic levels. Our review discusses salient points on the present status of seabirds in the Bay of Bengal Large Marine Ecosystem;despite overall low seabird numbers and biomass, this region harbors 9 species of terns, one of the most threatened bird group worldwide, which are known to breed in various marine habitats of Andaman and Nicobar islands, in addition to the coastal areas of mainland. Further, we elaborate on employing seabirds as potential indicators of this ecosystem and how they outscore other taxa in this aspect. Finally, we argue that it is essentially to fill the gaps in our knowledge about the BOBLME, mainly about the interplay between seabirds, climate change and fisheries.
