New research from Columbia confirms what Jennifer Francis and Jeff Masters described in my vid from 3 years ago. Weather Whiplash.

Columbia University:

This past July was Earth’s hottest month since record keeping began, but warming isn’t the only danger climate change holds in store. Recent years have seen a dramatic increase in the simultaneous occurrence of extremely cold winter days in the Eastern United States and extremely warm winter days in the Western U.S., according to a new study. Human-caused emissions of greenhouse gases are likely driving this trend, the study finds.

In the past three years alone, heat-related drought in the West and bitter cold spells in the East have pinched the national economy, costing several billion dollars in insured losses, government aid, and lost productivity. When such weather extremes occur at the same time, they threaten to stretch emergency responders’ disaster assistance abilities, strain resources such as inter-regional transportation, and burden taxpayer-funded disaster relief.

Understanding the physical factors driving extreme weather could provide decision-makers with more reliable information with which to prepare for weather disasters, while understanding the likelihood of droughts could help engineers better plan the development and management of infrastructure to provide reliable water supplies.

The new study, published in the Journal of Geophysical Research: Atmospheres, finds that the occurrence and severity of “warm-West/cold-East” winter events, which the authors call the North American winter temperature dipole, increased significantly between 1980 and 2015. This is partly because winter temperature has warmed more in the West than in the East, but the authors found that it also has been driven by the increasing frequency of a “ridge-trough” pattern, with high atmospheric pressure in the West and low atmospheric pressure in the East producing greater numbers of winter days with extreme temperatures in large areas of the West and East at the same time.