Uncertainty in Climate Change Projections due to Internal Variability

Abstract:

Climate change projections are subject to uncertainties in radiative forcing scenarios, model formulation, and internal variability of the climate system. In this talk, I will highlight the unavoidable contribution of internal variability to climate change projection uncertainty, with a focus on temperature and precipitation over North America and Eurasia. I will show that unpredictable, intrinsic variability of the climate system strongly influences the patterns and magnitudes of temperature and precipitation change in the coming decades, primarily through the influence of the large-scale atmospheric circulation. Implications for model validation, inter-model comparisons, regional climate modeling, and interpretation of observed climate trends shall also be discussed.