Credit: Melissa Gervais/Penn State The North Atlantic warming hole (NAWH), a region of reduced warming located in the North Atlantic Ocean, significantly affects the North Atlantic jet stream in climate simulations of the future, according to a team of researchers.
"It's called a hole because there is a lack of warming," said Melissa Gervais, assistant professor of meteorology and atmospheric science, Penn State, who used the Community Earth System model (CESM) to investigate the impact of the NAWH on atmospheric circulation and midlatitude jets.
Development of the NAWH is linked to a slowdown of the Atlantic Meridional Overturning Circulation, a large system of ocean currents that carry warm water from the tropics northwards into the North Atlantic, and is thought to be caused by an influx of fresh water coming from melting Arctic sea ice.
"These changes in SST patterns occur as the result of changes in ocean circulation and could have a significant impact on atmospheric circulation and the North Atlantic storm track in the future," said Gervais.
Gervais et al, Impacts of the North Atlantic Warming Hole in Future Climate Projections: Mean Atmospheric Circulation and the North Atlantic jet, Journal of Climate (2019).