Florian E. Roemer, Stefan A. Buehler, Kaah P. Menang
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引用次数: 0
Abstract
Earth’s climate feedback quantifies the response of Earth’s energy budget to temperature changes and thus determines climate sensitivity. The climate feedback is largely controlled by water vapor which absorbs both longwave radiation emitted by Earth and shortwave radiation from the Sun. For the clear-sky shortwave water vapor feedback λSW, a gap remains between process understanding and estimates from comprehensive climate models. Therefore, we present a hierarchy of simple models for λSW. We show that λSW is proportional to the change with temperature in the square of atmospheric transmissivity that depends on the atmospheric concentration of water vapor and its ability to absorb shortwave radiation. The global mean λSW is well captured by a simple analytical model that approximates the strong spectral variations in water vapor absorption, whereas its temperature dependence results from spectral details in water vapor absorption. With this study, we expand the conceptual understanding of an important but understudied feedback component.
期刊介绍:
npj Climate and Atmospheric Science is an open-access journal encompassing the relevant physical, chemical, and biological aspects of atmospheric and climate science. The journal places particular emphasis on regional studies that unveil new insights into specific localities, including examinations of local atmospheric composition, such as aerosols.
The range of topics covered by the journal includes climate dynamics, climate variability, weather and climate prediction, climate change, ocean dynamics, weather extremes, air pollution, atmospheric chemistry (including aerosols), the hydrological cycle, and atmosphere–ocean and atmosphere–land interactions. The journal welcomes studies employing a diverse array of methods, including numerical and statistical modeling, the development and application of in situ observational techniques, remote sensing, and the development or evaluation of new reanalyses.