Scientists Predict More Snowfall in Polar Regions, but Less Worldwide

A new climate model predicts that there will be an overall drop in snowfall across the globe, as a result of rise in carbon dioxide levels over the next century.

The climate model developed at the National Oceanic and Atmos­pheric Administration (NOAA) Geophysical Fluid Dynamics Laboratory (GFDL) projects that only the Earth's polar regions and highest altitudes will receive more snowfall.

Carbon dioxide is one of the primary greenhouse gases responsible for the increase in global temperatures. CO2 is naturally present in the Earth's atmosphere, but its emission levels have risen significantly due to human activities such as burning of fossil fuels.

Observations have shown that the atmospheric carbon dioxide has already increased by 40 percent from values in the mid-19th century. It is also been projected that the CO2 levels could exceed twice those values later this century. The doubling of atmospheric carbon dioxide would lead to an increase in global warming. As a result of warming, majority of the planet would experience less snowfall, said the researchers involved in the study.

In North America, the greatest reductions in snow­fall will occur along the north­east coast, in the moun­tain­ous west and in the Pacific North­west. Coastal regions from Virginia to Maine, as well as coastal Oregon and Washington will receive less than half the amount of snowfall that they currently receive.

However, the climate model projects that the cold regions of the globe will get more snowfall. As air warms, it can hold more moisture, leading to increased precipitation in the form of snow. Regions in and around the Arctic, Antarctica, the highest mountain peaks in the northwestern Himalayas, the Andes and the Yukon region will receive more snowfall after carbon dioxide levels double.

The predictions by the newly-developed climate model are in contrast to projections made by other models, which projected decline in snowfall for these high altitude regions. But the latest model is an improvement over previous models, taking more details about the world's topography. The new model's forecasts are consistent with current snowfall observations in these regions.

The findings of the study, "Controls of Global Snow Under a Changed Climate", are published in the Journal of Climate.