Global Cloud Climatology from Surface Observations: Analyses and Decadal Update

该项目将更新和分析陆地气象站和海洋船只的地面天气观测，以确定各种云类型的全球分布及其季节和日变化，并研究过去半个世纪云的变化情况。14年的陆地数据（1997-2010）将被添加到云观测数据库和云平均数据库中，这些数据库是由国家科学基金会（NSF）和国家海洋和大气管理局（NOAA）资助的先前赠款创建的。对年际变化和趋势的分析也将更新，以包括这14年。由此产生的数据库将涵盖55年的海洋数据和40年的陆地数据，更新后的数据库将有助于进行一些气候调查。云的辐射效应取决于云的日变化周期。将对这些数据库进行分析，以了解世界各地个别云类型的日周期。云类型的趋势将分别在白天和夜晚进行分析和比较，以研究过去几十年云辐射强迫的可能变化。在过去的几十年里，海洋上空的总云量略有增加，大陆上空略有减少。这些趋势是否会持续到最近几年，以及年际变化是否也表现出同样的负相关关系，将被调查。对云高与地面温度的关系进行了建模和遥感研究，将利用地面云观测中的基准高度报告，在年际时间尺度上对此进行研究。这项工作的更广泛影响是在气候研究领域。这一项目产生的数据库将广泛分发，供科学界使用，可能应用于气候建模、云过程研究、云的卫星观测评价以及气候变化的探测和归因。

This project will update and analyze surface synoptic observations from weather stations on land and ships in the ocean to determine the global distribution of the various cloud types and their seasonal and diurnal variations, as well as a study of how clouds have changed in the past half-century. Fourteen years of land data (1997-2010) will be added to the cloud-observations database and to the cloud-averages database created by the previous grants funded by National Science Foundation (NSF) and National Oceanic and Atmospheric Administration (NOAA). The analyses of interannual variations and trends will also be updated to include these 14 years. The resulting database will cover 55 years for the ocean and 40 years for land.The updated database will enable a number of climatic investigations. Clouds generally cause cooling in daytime but warming at night, so the radiative effects of clouds depend on their diurnal cycles. The databases will be analyzed for diurnal cycles of individual cloud types worldwide. Trends in the cloud types will be analyzed for day and night separately and compared, in order to investigate possible changes in the cloud radiative forcing over the past several decades. In past decades the total cloud cover has shown a slight increase over the ocean and slight decrease over the continents. Whether these trends continue into the more recent years will be investigated, as well as whether interannual variations also show the same anticorrelation. There have been modeling and remote-sensing studies of the relation of cloud height to surface temperature, which will be investigated on interannual time scales using the reports of base height in the surface-based cloud observations. The broader impacts of this work are in the area of climate research. The databases resulting from this project will be distributed widely for use by the scientific community, with potential applications in climate modeling, cloud process studies, evaluation of satellite observations of clouds, and in detection and attribution of climate change.