Ok. So. Last week the trans mega, which I usually avoid, had as the topic one of my weird obsessions so I engaged a bit there even though I’m not trans. I think freshwater systems are pretty interesting.

Well they had green lake in New York as the topic. Which is a meromictic lake. A meromictic lake is a lake where there is a stratified surface and deep water layers that do not mix. This causes interesting behaviors not normally seen in most lakes. For example, the buildup of concentrated dissolved carbon dioxide in the lower waters can sometimes be catastrophically released in a limnic eruption . You can read about the Lake Nyos disaster which killed 1700 people with an invisible cloud of CO2

It also means that the lower water is apoxic or devoid of oxygen so basically all life is on the surface layer. Which: there’s another lake, perhaps the second coolest lake in the world, Lake Malawi that is also meromictic. This lake seems fairly famous to me because it has something like 35% of the (known) cichlid species in the world. Another interesting fact about Malawi are the lake flies which, during breeding season, form groups so thick that the lake appears to have black smoke columns. Given the lake is meromictic, this grand diversity and density of life is even more interesting since it mostly takes place on the surface.

What’s that? You want to know what lake I think is the coolest in the world? Lake Baikal in Russia with 22% of the world’s freshwater. It has one of the world’s few freshwater seal species. And the trans siberian railway runs along the shore. It’s the world’s oldest lake and one of the deepest with many endemic species.