London, Dec 31 (IANS) Thanks to Arctic warming, thawing of permafrost, or frozen soil, is likely to hasten groundwater runoff, says a new study.
Permafrost is a soil frozen for at least two consecutive years or longer.

To probe how groundwater systems will evolve as surface temperatures rise, VF Bense School of Environmental Sciences, University of East Anglia, UK, and colleagues developed a model to simulate an idealised aquifer covered by a layer of permafrost.

They ran the simulation under three scenarios, starting with three initial surface temperatures (-2, -1.5, and -1 degrees Celsius, or 28.4, 29.3 and 30.2 degrees Fahrenheit), corresponding to different permafrost thicknesses.

In each case, they increased the average seasonal surface temperature by 3 degrees C (5.4 degrees F) over 100 years, an average of model predictions for temperature increase in the Arctic over the next century, says an East Anglia release.

After the warming period, in each scenario the temperature was then held constant for the next 1,100 years. The authors found that although the initial distribution of ice influences the response, in all cases groundwater flow to streams and rivers accelerates over time.

In fact, the results indicate that substantial increases in groundwater flow are likely over the next few centuries even if surface air temperatures stabilise at current levels.

The research was published in Geophysical Research Letters.