Climate change in Central America and Mexico: regional climate model validation and climate change projections

Abstract

Central America has high biodiversity, it har- bors high-value ecosystems and it's important to provide regional climate change information to assist in adaptation and mitigation work in the region. Here we study climate change projections for Central America and Mexico using a regional climate model. The model evaluation shows its success in simulating spatial and temporal variability of temperature and precipitation and also in capturing regio- nal climate features such as the bimodal annual cycle of precipitation and the Caribbean low-level jet. A variety of climate regimes within the model domain are also better identified in the regional model simulation due to improved resolution of topographic features. Although, the model suffers from large precipitation biases, it shows improve- ments over the coarse-resolution driving model in simu- lating precipitation amounts. The model shows a dry bias in the wet season and a wet bias in the dry season sug- gesting that it's unable to capture the full range of pre- cipitation variability. Projected warming under the A2 scenario is higher in the wet season than that in the dry season with the Yucatan Peninsula experiencing highest warming. A large reduction in precipitation in the wet season is projected for the region, whereas parts of Central America that receive a considerable amount of moisture in the form of orographic precipitation show significant decreases in precipitation in the dry season. Projected cli- matic changes can have detrimental impacts on biodiver- sity as they are spatially similar, but far greater in magnitude, than those observed during the El Nin ̃o events in recent decades that adversely affected species in the region.