Methane Bubbles Frozen in Lake Baikal

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.

Jigsaw Challenge: Astronomy Puzzle of the Day