Global warming is projected to spawn more extreme wet and dry weather around the world, according to a Rutgers-led study. Those extremes include more frequent dry spells in the northwestern, central and southern United States and in Mexico, and more frequent heavy rainfall events in south Asia, the Indochinese Peninsula and southern China.
One reason – subtropical stationary waves in northern summers, according to the study in the Journal of Climate. These planet-spanning waves are composed of persistent high-pressure systems over the North Pacific and North Atlantic and persistent low-pressure systems over Eurasia and North America, the study says. The high-pressure systems provide persistent conditions for dry weather, while the low-pressure systems fuel wet weather.
The intensity of subtropical stationary waves during northern summers increased from 1979 to 2013, and projections suggest the increase will accelerate as climate warms, the study says.