A device to measure the influence of spatially inhomogeneous cirrus on atmospheric radiation

The radiative effects of inhomogeneous cirrus fields will be studied by a combination of airborne measurements (radiation and microphysical properties), a three – dimensional radiative transfer model and a dynamic cloud – resolving cirrus model in the framework of the AIRTOSS (AIRcraft TOwed Sensor Shuttle) – Project in cooperation with the University of Mainz and the Max Planck Institute for Chemistry in Mainz. An instrumented aircraft (Lear-Jet) will sample spectral radiation above cirrus within a field campaign. From these data the microphysical cirrus properties will be retrieved and compared to simultaneous in situ measurements collected with the AIRTOSS, released on a 4-km long towing cable underneath the plane. In close collocation the spatial inhomogeneities of the sampled cirrus fields will be observed by an imaging digital CCD camera. In parallel, a cloud – resolving model will simulate microphysical cirrus fields. The combined in situ measured and retrieved microphysical cirrus fields as well a...