Vertical velocities in midlatitude cirrus: A comparison between in situ aircraft measurements and Doppler radar retrievals

Abstract:

Measurements of upper tropospheric vertical velocities are crucial for better understanding the interplay between atmospheric dynamics, ice supersaturations and the microphysical properties of cirrus clouds. In recent years, continuous observations from Doppler radar together with the development of novel retrieval techniques have led to a new and comprehensive observational dataset of vertical velocities within cirrus clouds. However, a thorough evaluation and comparison of these new retrieval techniques with in situ aircraft data is still lacking. In this contribution, we perform a detailed comparison of retrieved vertical velocities and turbulent eddy dissipation rates in midlatitude cirrus with in situ measurements from aircraft under various environmental conditions and cirrus cloud regimes. The comparison utilizes high-resolution turbulence data collected during the U. S. Department of Energy Small Particles in Cirrus field campaign and ground-based Doppler radar data collected at the Atmospheric Radiation Measurement Southern Great Plains site. Several case studies ranging from frontal cirrus to anvil cirrus are discussed.