How well RegCM reproduces mesoscale atmospheric phenomena in the Mexican neighborhood?

The orographic and oceanic influence in the atmospheric processes that impact Mexico generates a great variety of climates. One way to evaluate dynamical downscaling is to analyze how well regional models reproduce processes regional phenomena as easterly waves (EW), cold fronts (CF), Caribbean Low-level Jet (CLLJ) and the North American Monsoon (NAM). We evaluate the capabilities of the RegCM model to reproduce these processes, analyzing its impact using climate change scenarios for the Mexican area, including its seas (Gulf of Mexico and Eastern Pacific). The dynamical downscaling was performed for the historical period 1980-2009 and for the far future 2070-2099 under the RCP8.5 scenario. The regional RegCM model was forced with the CSIRO-MK36 global model for northern and southern Mexico.

The precipitation associated with the NAM is highlighted with the downscaling, a decrease is estimated in the projections in September. For the far future, the projected change of activity associated with EW would increase (decrease) in the Central Tropical Atlantic (40 ° W) to the west: Caribbean (to the east: Africa). The projection of kinetic energy change associated with CF would decrease in Mexican continental regions, increasing in the Caribbean. The CLLJ would increase in the projections for the future.