Extreme swings in Lake Chad’s water levels are not new. The lake has experienced wet and dry periods for thousands of years, according to paleoclimate research. More recently, variations in depth and extent were noted by French explorer Jean Tilho, who reported in 1910 that parts of the lake had dried up. But what is new is the way researchers are studying changes in the lake. the-ups-and-downs-of-lake-cha Lake Chad plays a starring role in apocalyptic scenarios. It is very vulnerable to drought and always has been. The recent drought itself is a fact. But is there a trend? The lack of such trends is features prominently in "denial" literature such as " Inconvenient Facts ." But are there trends? Gore is very clear about that, and the trends are all nasty. Both floods and droughts are attributed to climate change. I have yet to encounter a rebuttal of the "no trends" argument. Gore himself emphasizes the huge cost of hurricanes by dwelling on Katrina,...