NSF Award
2420081
Surface temperatures in the Arctic are increasing rapidly, at a rate that outpaces the global average. 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. This project aims to clarify the role that Arctic clouds play in modifying surface temperature and the amount of solar energy absorbed by the ground, sea ice, and ocean surfaces. 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. Understanding the role of Arctic clouds as they relate to Arctic warming and sea ice extent will help local communities adapt to rapidly changing environmental conditions and provide clues for the conditions that regions beyond the Arctic will encounter if they reach a similar level of warming. The investigator will mentor aspiring scientists by involving them in this research and will engage in efforts to improve climate science literacy among the public. <br/><br/>The amount of time spent in a clear versus cloudy Arctic cloud regime exerts a strong control on the amount of energy absorbed by the underlying surface, with implications for sea ice coverage, permafrost thaw, and Arctic amplification. However, the processes controlling those time scales and their response to climate change are unclear. This project will begin with a detailed characterization of the cloud regimes and their surface impacts at an Arctic observatory on the northern coast of Alaska. The air masses resulting in each cloud regime will then be tracked backwards in time with archived output from a high-resolution forecast model to determine how cloud-relevant properties such as temperature and humidity evolve and respond to surface conditions. There will be a particular focus on the time scales of cloud formation and dissipation and how those time scales depend on surface and atmospheric conditions. Finally, moisture fluxes will be added to the forecast model to construct moisture budgets along air mass trajectories and determine the processes that control moisture availability and cloud formation in the Arctic. Focusing on key time scales and the predictability of downwind cloud properties will provide a framework for understanding cloud formation and radiative effects that can be applied across the broad range of environmental contexts encountered in the Arctic.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
