Lake-Effect Zones in Climate Model Projections

Abstract:

Practitioners of climate information working in regions where lakes are important need to know if those features are represented in model simulations. If an important feature is not represented, then the practitioner is challenged with describing the uncertainty associated with the structure of the model. Depending on the practitioners application, other sources of information might be needed to address the uncertainty.

Here, we focus on the U.S. Great Lakes. We argue a first order usability requirement for practitioners is that the model produces a credible lake-effect. Specifically, we investigate whether traditional lake-effect precipitation zones are present in the models, which is an indicator that lake-land-atmosphere interactions are simulated. Our lake-effect analysis is conducted the set of global climate models from the Coupled Model Intercomparison Project version 5 (CMIP5) and two regional products, the North American Coordinated Regional Downscaling Experiment (NA-CORDEX) and the University of Wisconsin Regional Climate Model 4 (UW-RegCM4). The regional models are forced by the global models. We assess the quality of lake-effect information in terms of model realism (i.e., does the madeol have a lake effect) and bias, and discuss the relation between the ability of the global model to represent the lakes and related simulations in the regional models.