COTW: California Drought Continues

The severe California drought shown on this map from the US Drought Monitor has ramifications for the rest of country. The state grows a nearly half of the nation's fruit, nuts and vegetables.  The 20th century was a wet anomaly;  California's climate is due to turn 15% drier in coming decades as the region returns to its long-term norm for precipitation.

Once again as in the early thirties the panhandle of Texas and Oklahoma is severely parched.  This time there is something different: anthropomorphic climate change.  New research published in Geophysical Research Letters, says evidence has been found "that can trace the amplification of the dipole [western high pressure and eastern deep low pressure] to human influences."This dipole pattern is expected to intensify in the future, and historical data shows the dipole intensifying since the late 1970s. Researchers funded by NASA accurately simulated dipole conditions using a computer model that includes atmospheric greenhouse gases as a factor. When only natural variations are used such as the El Niño/La Niña event, only a weakening dipole is observed. American agricultural practices will have to adapt to the new environment as water resources are already stretched thin in California.