Regions of influence and environmental effects of Santa Ana wind event

Abstract

In the present study, we simulated an extreme Santa Ana wind event that affected northwestern Mexico and the southwestern United States in October 2007. The principal aim was to investigate the interaction of Santa Ana winds with the mountain chains of California and Baja California and the resulting meteorological perturbations over the Pacific Ocean. The Weather Research and Forecasting model coupled with a chemistry module (WRF-Chem) were used to analyze changes in meteorological variables and chemical variables such as dust concentration. The Santa Ana wind event analyzed modified meteorological conditions deteriorating climate welfare conditions and causing health threats in several densely populated areas through the formation of dust storms and spread of wildfires. The calculation revealed a decrease in relative humidity from 90% to less than 10% along the coasts of California and Baja California besides increasing temperature. The wind speeds intensified as a result of channeling through terrain gaps, causing the formation of finger-like structures of hot and dry air along the coast. The vertical behavior of the Santa Ana winds over the mountains of California and Baja California suggests that the descent of air masses from 2000 m to the surface could contribute to increasing coastal temperature. The intense winds led to the emission of dust, affecting several areas in Mexico and reducing air quality. Notably, large amounts of dust flowed to the Pacific Ocean off California and Baja California and also to the Gulf of California.