New NASA tool predicts which cities face floods due to ice melt

New York, Nov 16 (IANS) NASA scientists have developed a tool to forecast which cities are vulnerbale to flooding due to melting of ice in a warming climate.

It looks at the Earth's spin and gravitational effects to predict how water will be "redistributed" globally, BBC reported.

"This provides, for each city, a picture of which glaciers, ice sheets, (and) ice caps are of specific importance," the researchers were quoted as saying.

The research, detailed in the journal Science Advances, could provide scientists a way to determine which ice sheets they should be "most worried about".

The researchers explained that as land ice is lost to the oceans, both the Earth's gravitational and rotational potentials are perturbed, resulting in strong spatial patterns in sea-level rise (SLR). The pattern of sea-level change has been termed sea-level fingerprints.

"We lack robust forecasting models for future ice changes, which diminishes our ability to use these fingerprints to accurately predict local sea-level (LSL) changes," the researchers said.

So they set out to determine the exact gradient of sea-level fingerprints with respect to local variations in the ice thickness of all of the world's ice drainage systems.

"By exhaustively mapping these fingerprint gradients, we form a new diagnosis tool, henceforth referred to as gradient fingerprint mapping (GFM), that readily allows for improved assessments of future coastal inundation or emergence," the study said.

The researchers demonstrated that for Antarctica and Greenland, changes in the predictions of inundation at major port cities depend on the location of the drainage system.

For example, in London, local sea-level changes is significantly affected by changes on the western part of the Greenland ice sheet, whereas in New York, such changes are greatly sensitive to changes in the northeastern portions of the ice sheet, the tool showed.

--IANS

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