Climate Variability, Climate Change and Climate Simulations

My research interests are climate variability, climate change and climate simulations on both large and regional scales. My current focus on large-scale climate dynamics is on the high-latitude climate variability and climate change, mainly emphasizing (1) the amplifying effect of snow and sea ice albedo feedbacks, (2) the uncertainty in future climate prediction associated with the uncertainty of simulations of these feedbacks in climate models and (3) more importantly, the ways to constrain the feedbacks in future climate prediction. I am currently involved in the following projects in UCLA and would like to continue working on them in the forthcoming years: (1) the role of snow albedo feedback in climate change (in collaboration with Alex Hall and David Neelin in UCLA, and Chris Fletcher and Paul Kushner in the University of Toronto). (2) assessing simulations of sea ice albedo feedback in the Arctic (in collaboration with Alex Hall in UCLA, and Suki Manabe in GFDL, NOAA). (3) internal climate variability and climate change in the Southern Ocean (in collaboration with Alex Hall in UCLA and Suki Manabe in GFDL, NOAA). In the future, I would also like to study the role of cloud feedbacks in IPCC climate change experiments especially in the Arctic and Southern Ocean where cloud feedbacks interact with sea ice albedo feedback. Past climate change, e.g., induced by the variation in the earth orbital parameters is also what I would like to explore in the future using earth system models of intermediate complexity and full-blown climate models, as well as proxy data available. Understanding climate sensitivity in the past climate change is conducive to understanding climate sensitivity in anthropogenic climate change. 

Only by downscaling the impact of global climate change to regional scale can the consequence of this change be fully appreciated. This is why I am also interested in the regional climate change in conjunction with my large-scale interests. My current venture in regional climate dynamics is developing a modeling framework to understand regional climate of Southern California Bight. This is realized by coupling Weather Research and Forecast Model (WRF) to Regional Ocean Modeling System (ROMS) (I have been developing this in collaboration with Alex Hall and James McWilliams in UCLA, and Gretchen Mullendore in the University of South Dakota.) This framework facilitates downscaling the impact of global climate change to regional climate in coastal areas with complex topography where the interaction of atmosphere and ocean on fine scales is crucial to regional climate and its variability. This framework was proposed to study regional climate of Southeast Pacific, the core area of VAMOS Ocean-Cloud-Atmosphere-Land Study (VOCALS), a project with which I will likely be involved in the forthcoming years. In the future, I would like to use the framework to downscale the impact of the change in Southern Annular Mode (SAM) seen in recent decades to regional climate of the Antarctic Peninsula. This is an interesting work in light of the recent finding on the possible link of the formation in föhn wind on the lee side of the Antarctic Peninsula induced by the change in the SAM and the break up of the Larsen B shelf in 2002. I would also like to use the framework to study how the break up of the ice shelf affects local atmospheric and oceanic circulations.