Ice Sheet Height May Impact Global Climate as Ice Melts

It turns out that the height of an ice sheet doesn't just impact a regional climate; it may impact a global climate. Scientists have used computer models to simulate changing ice sheet height and have found that it could influence conditions around the world.

"There's a lot of evidence to suggest that changing the height of the ice sheets could change atmospheric circulation or even ocean circulation, but the role this forcing might play during Heinrich events has generally been overlooked," said William Roberts, one of the researchers, in a news release. "Our study aimed to see what effects such forcing might have."

A Heinrich event occurs when large masses of icebergs rapidly break free from ice sheets-like what happened during the last ice age. This is thought to have influenced global climate by interrupting ocean circulation patterns with a large influx of freshwater. Yet this latest research shows that variation in ice sheet height may also be to blame.

During a simulation of changing ice sheet height, the scientists found that there was a warm sea surface in the central North Atlantic. In addition, Florida became both warmer and wetter.

"Our results suggest that the simple paradigm of a Heinrich event causing climate change via freshwater inputs into the North Atlantic needs to be revised," said Roberts. "They also suggest that you can't use the climate changes that occur during Heinrich Events as a simple template for the changes that might occur from an influx of freshwater to the North Atlantic."

The findings reveal another factor that comes into play when it comes to a changing climate. As the ice sheets melt, their height could play a role in the changing global temperatures that can impact regions across the globe.

The findings are published in the journal Proceedings of the National Academy of Sciences.