sexta-feira, 12 de fevereiro de 2016
Record ozone hole may open over Arctic in the spring
By Eric Hand
Antarctica isn't the only place with an ozone hole. Lingering atmospheric pollutants and frigid air have carved an unusually deep hole in Earth's protective ozone layer over the Arctic, and it threatens to get deeper this spring. Atmospheric scientists are analyzing data from weather balloons and satellites for clues to how the ozone will fare when sunlight—a third factor in ozone loss—returns to the Arctic. But they are already worrying about how extra ultraviolet light might affect humans and ecosystems below and wondering whether climate change will make such Arctic holes more common or severe. By next week, 25% of the Arctic ozone will be destroyed, scientists warn. But if the winds of the polar vortex persist in keeping the stratosphere cold for another month, ozone losses will become severe.