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On both sides of the Bering Strait, summer sea ice has once more dropped to a level that is driving thousands of walruses onto coastal beaches.
 
Photos taken in Ryrkaypiy in Chukotka, Russia show an estimated 5,000 walruses hauled out in that spot, while across the strait in the United States, thousands more are hauled out near the village of Point Lay, Alaska. Villagers in both places are working to protect resting walrus herds from curious onlookers, as walruses hauled out in such large numbers on beaches are prone to being stampeded, killing smaller animals in the crush.
 
During the late summer and early fall, the Pacific walruses of the Chukchi Sea north of Alaska and of Russia’s Chukotka prefer to rest on sea ice over the shallow waters of the continental shelf.  In those areas they can readily access food on the seabed.

A University of Texas at El Paso (UTEP) study on children’s health has found that fourth and fifth graders who are exposed to toxic air pollutants at home are more likely to have lower GPAs.

As a raindrop falls through the atmosphere, it can attract tens to hundreds of tiny aerosol particles to its surface before hitting the ground. The process by which droplets and aerosols attract is coagulation, a natural phenomenon that can act to clear the air of pollutants like soot, sulfates, and organic particles. Atmospheric chemists at MIT have now determined just how effective rain is in cleaning the atmosphere. 

A new international study is the first to use a high-resolution, large-scale computer model to estimate how much ice the West Antarctic Ice Sheet could lose over the next couple of centuries, and how much that could add to sea-level rise. The results paint a clearer picture of West Antarctica’s future than was previously possible. The study has been published in The Cryosphere, an open access journal of the European Geosciences Union (EGU).

“The IPCC’s [Intergovernmental Panel on Climate Change] 4th and 5th Assessment Reports both note that the acceleration of West Antarctic ice streams in response to ocean warming could result in a major contribution to sea-level rise, but that models were unable to satisfactorily quantify that response,” says Stephen Cornford, a research assistant at the University of Bristol, UK and lead-author of the study.

Además de la fusión de los casquetes polares y la vida silvestre en peligro, una preocupación significativa entre los científicos es que el aumento de las temperaturas del Ártico provocados por el cambio climático podría resultar en la liberación de grandes cantidades de carbono encerrado en el suelo congelado de la región en forma de dióxido de carbono y metano. El permafrost del ártico se estima que contiene alrededor de un billón de toneladas de carbono, lo que potencialmente puede acelerar el calentamiento global. Las emisiones de carbono en forma de metano han sido motivo de especial preocupación porque en una escala de 100 años el efecto del metano es aproximadamente 25 veces más potente que el dióxido de carbono para atrapar el calor.