Guest Post by Willis Eschenbach
The Sahel, that stretch of harsh territory south of the Sahara desert, is a bleak region. I did some work there, in a couple three countries. I came away with the conviction that if every day, every person in the Sahel planted one fruit tree and killed one goat, in about twenty years it would be worth visiting.
Anthony highlighted some science by press release in “Climate change blamed for dead trees in Africa“. The press release is about a paper that won’t be published until this coming Friday. The lead author provided the following quotes for the press release. (emphasis mine)
“Rainfall in the Sahel has dropped 20-30 percent in the 20th century, the world’s most severe long-term drought since measurements from rainfall gauges began in the mid-1800s,” said study lead author Patrick Gonzalez, who conducted the study while he was a visiting scholar at UC Berkeley’s Center for Forestry. “Previous research already established climate change as the primary cause of the drought, which has overwhelmed the resilience of the trees.”
I thought, “Really”? Because I was sure I remembered all kinds of recent articles about the “greening of the Sahel”. In any case, I’ll take any excuse to learn something new. So I went off to see what the rainfall records had to say about the “world’s most severe long-term drought”.
I found three rainfall records that covered the Sahel in the time period from 1901 to the present. Two (CRU and GPCC) are available from KNMI Climate Explorer, and one (Sahel Index) can be downloaded from the University of Washington. I used the same geographical area as used by the University of Washington, from 10-20°N, and from 10°W to 20°E. The results are shown in Figure 2.
Figure 2. Three different estimates of rainfall in the Sahel region, 10-20°N, 10°W-20°E. Bright red line shows the 9 year Gaussian average of the median of the three estimates. Photo is of the Sahel region, Senegal
I’m sorry, but I’m not seeing either a “severe long-term drought”, or a drop of “20-30 percent in the 20th century”, or a human fingerprint in that record. Modern times are drier than mid-20th century, but not much different from the first part of the century. Rainfall has gone up, and it has gone down, and then back up again. Nor is there any obvious correlation with the general warming of the planet over the same time period. Given the close agreement of the three records, I think we can have reasonable confidence in the data.
I did enjoy his claim that “Previous research already established climate change as the primary cause of the drought.” Climate change causes droughts? Interesting theory. Does climate change also cause not-droughts? I wonder what else is caused by climate change, given that the climate has always been changing.
Finally, I was not mistaken that I remembered articles about the “greening of the Sahel”. Here’s information from the Encyclopedia of the Earth, from National Geographic, and from the Global Warming Policy Foundation regarding how the Sahel has been getting, not drier and browner, but wetter and greener ever since the 1980s.
Conclusions? My only conclusion is that folks are getting desperate for funding, and that the manufacturing of climate pseudo-catastrophes is a booming cottage industry.
PS—I’m dead serious about planting trees and killing goats. The main cause of what desertification occurs in the Sahel is humans, but not by way of CO2. We do it by burning whatever will burn to cook our food, and by letting the goats destroy the rest.