When a river changes course on its flood plain, it can leave an entire bend of the river cut off from the new flow, forming an oxbow lake. Seen in bright blue in this shot of the Songhua River in northeast China, they are usually narrow crescents. Read the rest

Landsat imagery of the Ucayali river in Peru shows it meandering over a period of several years; an oxbow lake forms, islands grow and fade in the channel, and a smaller river is "eaten" at the top left. [Hindered Settling, via]

P.S. Looks like it might be a bad idea to build houses on flood plains. Read the rest

Captured at Katmai National Park in Alaska. Read the rest

The diving gear might be a bit of a tip-off, but this fellow isn't sat on a log, fishing. In fact, he's 90ft underwater, posing above the murk that forms where fresh and salt water meet. Photographer Anatoly Beloshchin captured these and many other stunning pictures in and around the depths. [Daily Mail] Read the rest

I was born in 1981 and, because of that, I largely missed the part of American history where our rivers were so polluted that they did things like, you know, catch fire. But it happened. And, all things considered, it didn't happen that long ago. The newspaper clippings above are from a 1952 fire on Ohio's Cuyahoga river. Between 1868 and 1969 that river burned at least 13 times.

That's something worth remembering — not just that we once let our waterways get that trashed, but also the fact that we've gone a long way towards fixing it. We took 200 years of accumulating sewage and industrial degradation and cleaned it up in the span of a single generation. At Slate, James Salzman writes about that reversal of environmental fortune, a shift so pronounced — and so dependent upon a functioning government in which a diverse spectrum of politicians recognize the importance of investing in our country's future — that it seems damned-near impossible today.

... discharging raw sewage and pollution into our harbors and rivers has been common practice for most of the nation’s history, with devastating results. By the late 1960s, Lake Erie had become so polluted that Time magazine described it as dead. Bacteria levels in the Hudson River were 170 times above the safe limit. I can attest to the state of the Charles River in Boston. While sailing in the 1970s, I capsized and had to be treated by a dermatologist for rashes caused by contact with the germ-laden waters.