The Project

The Earth's radiation budget is a vital part of the climate system: Absorption of solar radiation and heat loss to space determine global temperatures and drive the dynamics. The amount of absorbed solar radiation depends largely on how much is reflected by clouds. Determining the effect of clouds on the radiation budget has therefore been identified by the Intergovernmental Panel on Climate Change as a key area of scientific uncertainty in climate change prediction. However, absorption and scattering by ubiquitous ice clouds (cirrus) consisting of ice crystals of complicated non-spherical shapes are difficult to calculate.
Our goals are to provide
  • a long-term survey of cirrus micro- and macrophysical properties from both remote sensing and in-situ measurements
  • correlations between cirrus properties and the state of the atmosphere
  • a study of their effect on the reflection and absorption of solar and thermal radiation
This information is essential for the understanding of changes in clouds expected by a global climate change.
  • 8-year survey of cirrus physical and microphysical properties from TOVS retievals
  • correlations between cirrus properties and the state of the atmosphere
  • radiative flux sensitivity to changes in cirrus microphysical properties
  • software tools for data exploitation from Earth observing instruments on the European MSG satellite
  • improved cirrus radiative transfer code for GCMs and regional forecast models