Department Seminar: Qinghua Ding

Title: Improving climate projections and simulations through observation-constrained model capabilities

Abstract: The significant role played by large-scale atmospheric circulation changes in modulating global climate in recent decades has long been known. However, the capacity of climate models in replicating these observed variations in circulation, particularly with regard to their interannual and interdecadal components, remains uncertain. Given this, I propose a recalibration of model simulations and projections in the mid- and high- latitudes, taking into account both influences of external forcing and internal circulation variability on circulation variability. Assuming that the climate sensitivity of simulated circulation to both internal and external forcing remains unchanged in the coming decades, this recalibration approach yields some novel insights that cannot be easily learned from the uncalibrated ensemble. I will introduce this idea at the beginning of my presentation, followed by a showcase of my two recent research practices guided by this concept: one related to Arctic sea ice projections and the other concerning seasonal forecasts of recent Southern California droughts. Through these two examples, my primary aim is to underscore the crucial importance of factoring in the role played by large-scale circulation changes in improving climate simulations and future projections.