Seasonal Transitions in the Next Climate Assessments

Abstract:

A stated research goal for climate assessments is to “improve understanding, modeling and projections of climate changes, especially at the regional scale” (NCA 2014, Ch 29.) Here we present a case study using the Northeast U.S., to evaluate information contained in projections of the monthly mean annual cycle that may be important for understanding the projected changes in the physical climate system. Indeed, there is information that is otherwise masked by seasonal and annual mean averages, and this information will likely have implications for evaluating impacts and for developing adaptation strategies. We analyse 16 models from the CMIP5 Historical and RCP8.5 archives and evaluate monthly mean changes in the context of expected changes in the annual cycle of global climate system. It will be argued that improved understanding of seasonal transitions has potential to increase confidence in projections, and to provide additional information of use to the impacts and decision-maker communities.