2024年12月29日
Methane Bubbles Frozen in Lake Baikal
Image Credit & Copyright: Kristina Makeeva
Explanation: What are these bubbles frozen into Lake Baikal? Methane. Lake Baikal, a UNESCO World Heritage Site in Russia, is the world’s largest (by volume), oldest, and deepest lake, containing over 20% of the world’s fresh water. The lake is also a vast storehouse of methane, a greenhouse gas that, if released, could potentially increase the amount of infrared light absorbed by Earth’s atmosphere, and so increase the average temperature of the entire planet. Fortunately, the amount of methane currently bubbling out is not climatologically important. It is not clear what would happen, though, were temperatures to significantly increase in the region, or if the water level in Lake Baikal were to drop. Pictured, bubbles of rising methane froze during winter into the exceptionally clear ice covering the lake.
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贝加尔湖冻结的甲烷气泡
影像提供与版权: Kristina Makeeva
说明: 冻结在贝加尔湖气泡里的是什么？甲烷。位于俄罗斯的贝加尔湖，是联合国教科文组织的世界遗址之一，也是世界上体积最大、最古老及最深的湖泊，拥有世界百分之二十以上的淡水储量。这座湖泊也是庞大的甲烷（一种温室气体）储存库，一旦释放出来，可能会造成地球大气对红外光吸收的增加，导至地球平均温度的上升。很幸运的，目前释出的甲烷量，尚未对气候造成重大影响。然而，如果此区的温度大幅上升，或者贝加尔湖的水深显著下降，后果会如何目前仍然不明。影像中的这些气泡，是冬天来临在上浮时，被冻结在这座湖泊无比澄澈的湖冰里。
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