全球气候数据集生成及气候变化应用研究

Production of the global climate data records and applications to climate change studies

科技部在"十三五"期间部署的国家重点研发计划"全球变化及应对"专项资助了"全球气候数据集生成及气候变化关键过程和要素监测"研究项目。项目围绕由全球气候观测系统提出的基本气候变量,完善地空天基观测体系,生成中国首套以遥感数据为主体的涵盖大气、海洋和陆表长时间序列、高精度、高时空一致性的产品,即气候数据集,动态监测全球变化关键过程和要素。

The research project entitled, ＂Generation of global climate data records and their use for monitoring the key variables and processes of climate change,＂ was recently funded by the Chinese Ministry of Science and Technology under the Global Changes and Responses Program. This project focuses on the essential climate variables proposed by the global climate observing system. It aims to improve surface-air-space observing systems; produce long-term, highly accurate, and highly spatiotemporal consistent satellite products （i.e., climate data records, CDRs） of the atmosphere, ocean, and land surfaces; and monitor the key variables and processes of climate change dy- namically. This project will produce the first CDR suite in China. This research project is divided into four. The first three sub-projects fo- cus on the satellite product generation of the atmosphere, ocean, and land surfaces. Each of these three sub-project includes ground observa- tion, inversion and fusion methods of remote sensing data, and production and application demonstration of climate dataset. Ground observa- tion is mainly used for algorithm development, product validation, and application demonstration. Sub-project 4 will comprehensively as- sess these satellite products and use them for climate change studies. Sub-project 1 on the atmosphere will mainly focus on the variables that are essential for climate change studies, such as aerosol optical thickness, cloudiness, precipitation, CO2, ozone, solar incident radiation, re- flected solar radiation, outgoing long wave radiation, and energy imbalance. Nine CDRs will be generated at the end. The application demonstration will be based on the long-term atmospheric climate dataset; it will be combined with foreign satellite-related products to study the global climate effects of aerosol, dynamic monitoring of polar ozone concentrations, energy balance of the Earth, and other applications. Sub-project 2 on the ocean will mainly focus on methods and techniques for producing a total of 21 products, including the balance components of ocean energy （i.e., shortwave incident solar radiation, shortwave broadband albedo, longwave downward radiation, emissivity, and net radiation）, dynamic environmental parameters and processes of the ocean （i.e., sea surface wind, ocean wave, surface flow, sea surface temperature, sea surface salinity, sea surface temperature, and oceanic ice color （reflectance, chlorophyll concentration, particulate organic carbon, and primary productivity））, and sea ice （i.e., concentration, thickness, and drift）.At the end, 17 of these will be generated as ocean CDRs. Their applications to the global ocean matter and energy transport will be demonstrated based on the global ocean climate data set for the major estuarine water changes of the world in response to global climate change. Sub-project 3 for land surfaces will mainly focus on 20 variables that characterize the key processes of climate change, including the global energy balance of land surfaces （i.e., shortwave incident radiation, shortwave broadband albedo, longwave downward radiation, land surface emissivity, land surface temperature, and net radiation）, water cycle （i.e., evapotranspiration, water surface dynamics, and wetland）, carbon cycle （i.e., leaf area index, fractional photo synthetically active radiation absorbed by green vegetation, vegetation coverage, forest biomass, gross primary productivity, net primary productivity, res- idential area, land cover, and fire burned area）, and polar and cryosphere （i.e., elevation and area of ice surfaces, snow cover, snow water equivalent, and freezing and thawing of permafrost）. At the end, 15 of these products will be generated as land CDRs. The application demonstration component will include assimilating these data products into land surface process models; analyzing the effect of these products on the diagnostic ability of temporal and spatial characteristics of climate change; and quantifying the scientific values of these products in characterizing regional carbon cycle, water cycle, and energy balance. The atmospheric, oceanic, and terrestrial CDRs will be analyzed in Sub-project 4 by using the key process of global change as the constraint. They will be tested based on their spatiotemporal and logical consistency. Basic global change indicators will be proposed based on the entire process of acquisition and analysis of information data of global change. We will also determine the states and trends of the key processes, evaluate their causes and effects comprehensively, and investigate direct evidence of the roles played by key processes and elements in global climate change.