Warming oceans could melt polar ice sheets faster than expected

Scientists have long believed that warming air from climate change may speed up melting of polar ice glaciers.

In previous researches scientist had focused mainly on how rising atmospheric temperatures would affect ice sheets.

Warming oceans also speed ice melting
Now a new study has suggested that apart from being exposed to the warmer air, the higher temperature being carried by the warm water seeping through these ice reserves could accelerate the melting of the ice sheets frozen for million of years.

"Ocean warming is very important compared to atmospheric warming, because water has a much larger heat capacity than air," stated study lead researcher Jianjun Yin of the University of Arizona (UA).

"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," Yin added.

The research based on 19 state-of-the-art climate models revealed that the oceans surrounding Greenland and Antarctica could warm by up to 2C and 0.6C respectively over the century.

Global warming could heat up subsurface ocean layers
The UA researchers suggested that the subsurface ocean layers surrounding the polar ice sheets will warm substantially as global warming progresses.

The research based on 19 state-of-the-art climate models revealed that the oceans surrounding Greenland and Antarctica could warm by up to 2C and 0.6C respectively over the century.

By 2010, the subsurface ocean along the Greenland coast could warm as much as 3.6 degrees Fahrenheit, while the warming along the coast of Antarctica would be somewhat less, at 0.9 degree Fahrenheit, which could erode away the ice sheets much faster than warmer air alone.

Earth’s sea level would rice at alarming rate
According to research findings, subsurface ocean warming could accelerate ice-sheet melting over the next century, resulting in greater sea level rise that could exceed 3 feet.

The drastic increase in ocean warming could induce more water ending up on the seas when the ice sheets below the surface begin eroding.

“This means both Greenland and Antarctica are probably going to melt faster than the scientific community previously thought,” said co-author Prof Jonathan T. Overpeck, also of the University of Arizona.

“This paper adds to the evidence that we could have sea level rise by the end of this century about 1m and a good deal more in succeeding centuries.”

Overpeck and Yin's study was published Sunday in the journal 'Nature Geoscience.'