Cloud, Aerosol, Radiation Cloud and Aerosol: Modulators of the Earth climate
Microphysical and radiative properties of atmospheric clouds and aerosols and their interactions are fundamental knowledge to understand the Earth climate system.
The Intergovernmental Panel on Climate Change has identified clouds and aerosols as the largest uncertainties in the Earth’s climate system in terms of radiative forcing. Aerosols influence the Earth’s radiative balance by reflecting and absorbing solar and terrestrial radiation (i.e., the aerosol direct effect) and by changing cloud albedo (i.e., the aerosol first indirect effect) and lifetimes of clouds (i.e., the aerosol second indirect effect). However, current studies show that there are large uncertainties in compositions, concentrations, and life cycle of aerosols and hence variations in the radiative forcing. Although the current globally averaged net cloud radiative forcing is estimated on the order of -20 Wm-2, it is uncertain how changes in cloud properties associated with anthropogenic forcing affect the radiative impact of clouds on regional and global scales. Our understanding of the processes that control the occurrence and properties of cloud is thus fundamental to eventual improvements of their correct representation in regional and global scale models. Further, recent studies showed the importance of aerosol-cloud interactions, but large uncertainties in their impacts on Earth’s radiation budget.
Our group has been exploring the microphysical and radiative properties of clouds and aerosols using in-situ aircraft measurements, laboratory experiments, and theoretical calculations including a development of satellite retrieval algorithms. Based on these experiences, we are building new databases of microphysical and scattering properties of atmospheric particles (aerosol and cloud particles), to establish an in-situ measurement platform in Korea, and to develop new remote sensing algorithms, which are fundamental to develop and improve microphysical and radiative schemes used in numerical models.
