Interactions Between Different Aerosol and Cloud Types

Clouds and aerosols have complicated interactions; a major uncertainty in the study of aerosol effects on climate is to identify how different types of aerosol affect the properties of different types of clouds. Because of this, adjustments of cloud in response to aerosol loading are not well represented in climate models, and this has been recognized as one of the major sources of uncertainty in our knowledge of the climate system according to the IPCC AR5

Using collocated CALIPSO and CloudSat measurements, together with other A-Train satellite observations and radiative transfer calculations, this study investigates how different types of aerosols affect different types of clouds, and thus provide insights for future aerosol-cloud parameterizations in climate models. In particular, we analyze the impacts of different aerosol types on the properties and vertical structure of different cloud types using multi-satellite observations.

We aim to answer the following questions:
1. How do different types of aerosol affect the microphysical and macrophysical properties of different types of cloud?
2. Is there any significant difference in the aerosol-cloud relationship between different regions where the same dominant type of aerosol is identified? If yes, what factors may account for the regional difference?
3. What are the magnitudes (in terms of W/m2) of the radiative forcings of different aerosol types in clear-sky and cloudy-sky (TOA, surface and atmosphere)?
4. What is the magnitude (in terms of W/m2) of cloud radiative forcing change resulted from aerosol influence on clouds?

This study takes full advantage of collocated measurements over the globe from CloudSat/CALIPSO and other A-Train satellites to characterize the influence of various aerosol types on different types of cloud and to quantify potential impacts on regional climate.