Comparing the 2012 drought to the Dust Bowl droughts of the 1930s

[phantom power]

An important fact to remember is that the 2012 drought is--so far--only a one-year drought. Recall that 2011 saw record rains that led to unprecedented flooding on the Mississippi, Ohio, and Missouri Rivers. In contrast, the great droughts of the 1950s and 1930s were multi-year droughts. The Dust Bowl drought of the 1930s lasted up to eight years in some places, with the peak years being 1934, 1936, and 1939 - 1940. Once the deep soil dries out, it maintains a memory of past drought years. This makes is easier to have a string of severe drought years. Since the deep soil this summer still maintains the memory of the very wet year of 2011, the 2012 drought will be easier to break than the Dust Bowl droughts of the 1930s were.

In addition, a repeat of the dust storms of the 1930s Dust Bowl is much less likely now, due to improved farming practices. In a 2009 paper titled, Amplification of the North American "Dust Bowl" drought through human-induced land degradation, a team of scientists led by Benjamin Cook of the Lamont-Doherty Earth Observatory explained the situation:

During the 1920s, agriculture in the United States expanded into the central Great Plains. Much of the original, drought-resistant prairie grass was replaced with drought-sensitive wheat. With no drought plan and few erosion-control measures in place, this led to large-scale crop failures at the initiation of the drought, leaving fields devegetated and barren, exposing easily eroded soil to the winds. This was the source of the major dust storms and atmospheric dust loading of the period on a level unprecedented in the historical record.

Using computer models of the climate, the scientists found that the Dust Bowl drought was primarily caused by below-average ocean temperatures in the tropical Pacific and warmer than average ocean temperatures in the Atlantic, which acted together to alter the path of the jet stream and bring fewer precipitation-bearing storms to the Central U.S. However, the full intensity of the drought and its spatial extent could not be explained by ocean temperature patterns alone. Only when their model included the impact of losing huge amounts of vegetation in the Plains due to poor farming practices could the full warmth of the 1930s be simulated. In addition, only by including the impact of the dust kicked up by the great dust storms of the Dust Bowl, which blocked sunlight and created high pressure zones of sinking air that discouraged precipitation, could the very low levels of precipitation be explained. The Dust Bowl drought had natural roots, but human-caused effects made the drought worse and longer-lasting. The fact that we are experiencing a drought in 2012 comparable to the great Dust Bowl drought of the 1930s--without poor farming practices being partially to blame--bodes ill for the future of drought in the U.S. With human-caused global warming expected to greatly increase the intensity and frequency of great droughts like the 2012 drought in coming decades, we can expect drought to cause an increasing amount of damage and economic hardship for the U.S. Since the U.S. is the world's largest food exporter, this will also create an increasing amount of hardship and unrest in developing countries that rely on food imports.

http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2188


Figure 2. Black Sunday: On April 14, 1935 a "Black Blizzard" hit Oklahoma and Texas with 60 mph winds, sweeping up topsoil loosened by the great Dust Bowl drought that began in 1934.

[MuseRider]

1. There are a lot of us

who are in year 2 or more. My little part of Kansas was terribly dry and hot last summer with only a slight winter and only a dusting of snow. As I have said elsewhere, I had to bury a horse a month ago and the man who dug the grave told me the soil was dusty dry at 6 feet.

I hope the areas that are in year one and had lots of rain last year break it and that we will at least have a little more rain next year. My crop was horrible, horrible last year too. Walking on the grass is noisy. Yuk. I had 5 ponds and now I have 2 and they are rapidly losing water. One will be dry next month, we re-dug it last year because it was so dry and the bank needed work. The other, my big pond is down at least 3 feet.

It will be interesting.

[Junkdrawer]

2. I know I sound like a broken record, but we're losing the Arctic Sea Ice....

Simple science fact: it takes 80 times as much energy to melt ice than it does to raise the temperature of water 1 degree C.

Will that mean an 80 C Arctic Ocean when the sea ice is gone? Of course not. But it will mean something. And the world's climate will, almost certainly, change and change dramatically.

10 years ago, the date for an Ice Free Arctic was 2100...then it was 2030. Now it's before the decade is out.