Warming air from climate change isn't the only thing that will speed ice melting near the poles — so will the warming water beneath the ice, a new study points out.
Increased melting of ice in Greenland and parts of Antarctica has been reported as a consequence of global warming, potentially raising sea levels. But little attention has been paid to the impact of warmer water beneath the ice.
Now, Jianjun Yin of the University of Arizona and colleagues report the warming water could mean polar ice melting faster than had been expected. Their report was published Sunday in the journal Nature Geoscience.
While melting floating ice won't raise sea level, ice flowing into the sea from glaciers often reaches the bottom, and grounded ice melted by warm water around it can produce added water to the sea.
"Ocean warming is very important compared to atmospheric warming because water has a much larger heat capacity than air," Yin explained. "If you put an ice cube in a warm room, it will melt in several hours. But if you put an ice cube in a cup of warm water, it will disappear in just minutes."