Causes and Implications of Extreme Atmospheric Moisture Demand during the Record-Breaking 2011 Wildfire Season in the Southwestern United States*

摘要: AbstractIn 2011, exceptionally low atmospheric moisture content combined with moderately high temperatures to produce a record-high vapor pressure deficit (VPD) in the southwestern United States (SW). These conditions record-low cold-season precipitation cause widespread drought and extreme wildfires. Although interannual VPD variability is generally dominated by temperature, 2011 was also driven lack of moisture. The May–July dewpoint SW 4.5 standard deviations below long-term mean. Lack promoted already very dry soils amplified strong ocean-to-continent sea level gradient upper-level convergence that drove northerly winds subsidence upwind over SW. Subsidence divergence rapid surface SW, suppressing southerly imports removing from soils. Model projections developed for fifth phase Coupled Mod...