Authors
Kara Hartig (CIRES,NSIDC), John Cassano (CIRES,NSIDC), Matthew Shupe (CIRES,NSIDC,NOAA/PSL), Amy Solomon (CIRES,NSIDC,NOAA/PSL)

Abstract

Arctic clouds help to determine surface temperatures and sea ice extent, yet clouds and the ways in which they interact with atmospheric and surface conditions represent some of the largest sources of uncertainty in climate models. By combining observations from the North Slope of Alaska with high-resolution regional models, this research will investigate how clear and cloudy conditions develop, how upwind conditions control cloud properties, and the impact that clouds have on the energy dynamics of underlying surfaces. With an initial focus on explaining the liquid water path of winter clouds, we have found the absolute temperature and moisture at cloud level to be a poor predictor of liquid water path. Instead, cloud liquid is set first by the vertical extent that is saturated with respect to water, implying a fairly consistent liquid water content across conditions, and second by the departure from a moist adiabat, indicative of entrainment, diabatic cooling, and other processes. The next step will be to determine which meteorological conditions or air mass histories set the saturated depth and adiabaticity so that we can characterize clouds into regimes by their favorability for liquid water production.