“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.”
The study, which is scheduled for publication Friday, Dec. 16, in the Journal of Arid Environments, was based upon climate change records, aerial photos dating back to 1954, recent satellite images and old-fashioned footwork that included counting and measuring over 1,500 trees in the field. The researchers focused on six countries in the Sahel, from Senegal in West Africa to Chad in Central Africa, at sites where the average temperature warmed up by 0.8 degrees Celsius and rainfall fell as much as 48 percent.
They found that one in six trees died between 1954 and 2002. In addition, one in five tree species disappeared locally, and indigenous fruit and timber trees that require more moisture took the biggest hit. Hotter, drier conditions dominated population and soil factors in explaining tree mortality, the authors found. Their results indicate that climate change is shifting vegetation zones south toward moister areas.
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  IMAGE:Rainfall in the African Sahel declined more than anywhere else in the world in the period of recorded measurements, causing increased aridity, as evidenced by this dust storm in Senegal.Click here for more information. |
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“In the western U.S., climate change is leading to tree mortality by increasing the vulnerability of trees to bark beetles,” said Gonzalez, who is now the climate change scientist for the National Park Service. “In the Sahel, drying out of the soil directly kills trees. Tree dieback is occurring at the biome level. It’s not just one species that is dying; whole groups of species are dying out.”
The new findings put solid numbers behind the anecdotal observation of the decline of tree species in the Sahel.
“People in the Sahel depend upon trees for their survival,” said Gonzalez. “Trees provide people with food, firewood, building materials and medicine. We in the U.S. and other industrialized nations have it in our power, with current technologies and practices, to avert more drastic impacts around the world by reducing our greenhouse gas emissions. Our local actions can have global consequences.”
Other co-authors of the study are Compton J. Tucker, senior earth scientist at NASA’s Goddard Space Flight Center, and Hamady Sy, country representative for Mauritania at the Famine Early Warning Systems Network.
Funding from NASA and the U.S. Geological Survey helped support this research.
During the Holocene Optimum 6000 years ago, the Sahara was warmer and wetter than now. During the last glacial max, the Sahara was much bigger. High temps do not mean drought.
“People in the Sahel depend upon trees for their survival,” said Gonzalez. “Trees provide people with food, firewood, building materials and medicine. We in the U.S. and other industrialized nations have it in our power, with current technologies and practices, to avert more drastic impacts around the world by reducing our greenhouse gas emissions. Our local actions can have global consequences.”
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Marcel Leroux collected data and explained it in his PhD thesis, updated in 2002 and published 2002 – The Meteorology and Climate of Tropical Africa, Springer Verlag, 2002, 548 p.+ CD 250 maps (ISBN 3-540-42636-1).
Leroux explained that drought is linked to paleoclimatic cold periods and not warm periods. So of course the Sahel Drought is linked to “climate change” but contrary to the propagandist Gonzalez assertion, it cannot be caused by GHG inducing global warming.
History tells us otherwise. eom.
I can do this study one better. During the depths od the last glaciation over 7 trillion trees were killed by cold/compression over vast areas of the earth. From the tree line in northern Canada south into the US. From northern Siberia south to central Asia. Northern Europe and else where. The earth lost large quanity of oxygen input to the atmosphere and CO2 storage.
What is happening now in Africa to the trees is slight compared to that.
Steve Keohane says:
December 12, 2011 at 8:16 am
“In the western U.S., climate change is leading to tree mortality by increasing the vulnerability of trees to bark beetles,” said Gonzalez, who is now the climate change scientist for the National Park Service.
Utter crap. We need weeks of -20°F to kill off the beetles. How often has that happened. Not in the 40+ years I’ve been in Colorado.
Steve-
Gonzalez is referring to the fact that Ponderosa Pines need a given amount of water in able to naturally prevent the bark beetles from eating through its thick bark and ultimately killing it. Ponderosa Pines do this by excreting a rather large amount of sap in order to cover and kill the beetle as it attempts to make its way into the tree core. During droughts the trees cannot produce the necessary amounts of sap due to the lack of summer/monsoon moisture. So, his statement is factually correct since he did not state anthropogenic climate change. However it would have been better stated utilizing the word “drought” instead of “climate change”.
Very interesting. Everything I’ve read until today indicated that rainfall in the Sahel has been increasing for decades. CO2-induced climate change was predicted to increase rainfall there so dramatically as to encroach upon the Sahara.
It has been my understanding that the Sahara desert area used to be lush. Also that, this “desertification” (Is that a word?) has been ongoing for thousands of years. So what’s new here?
Oh, now it’s anthropogenic(That is a word.). I feel so guilty.
And, as sources of firewood, do the indigenous people cut down trees? Are there species of trees which make better firewood? Could that be a factor?
Logging, as mentioned above is also a factor, as it changes the species group which then re-inhabits the land. Given time the forest succession would bring back the original long-term species, lacking more outside factors or more natural climate change (it’s so nice to use “climate change” with its real meaning).
In New England we avoid burning pine, unless you are into chimney fires. Really dry pine does not spit and crackle, but it is just as good as younger pine at making creosote.
And then there is the grazing animals eating saplings of specific species. Another factor?
If the authors are indicating climate change, they need to be quite specific, since it means global warming to one group (the Team et al.) and entirely natural processes to the rest of the real world.
NC Skeptic says:
Just what does this have to do with NASA? Someone needs to get NASA back on topic.
Probably got to do with the first item on the NASA “charter” :
(1) The expansion of human knowledge of the Earth and of phenomena in the atmosphere and space.
Garrett,
You’re forgetting Muslim outreach.☺
Owen says:
“The Climate Liars attribute everything to Co2. I wonder if we can blame their lies and corruption on excess Co2 in the atmosphere.”
There you go; there must be an atmospheric CO2 concentration threshold above which certain genetically susceptible individuals’ critical thinking skills are diminished while their naive “bandwagon” instinct is enhanced.
Joe Crawford says:
It’s amazing how you can arrive at the answer you want by closely picking the start-end dates of your study. Quoting from a 2008 article …
Pretty please, tell us why your cherry-picking of an appropriate article is any better? Your article refers to the period 1980-2008 (28 years). The article above refers to the period 1954-2002 (48 years). Objectively, which do you think is the most pertinent period from a statistical viewpoint?
Having said that, the recent greening of the Sahel is definitely real. The big questions are how long will it continue and what are the long term forecasts?
So “They found that one in six trees died between 1954 and 2002.” That means five out of six trees lasted nearly half a century or more. In the wood i walked through in the UK yesterday there were precious few trees i would judge to be that old and far more than one in six were dead.
Smokey: I’m assuming that was just a lazy joke on your part. My apologies for not laughing. I’m not too fond of straw-man rebuttals.
Lack of humidity results in Higher daytime and lower nighttime temps. War and Marxist non-sense have had more impact on the Sahel then all other factor combined.
I am sure none of this has anything to do with the explosion of nomadic and static popukation growth in this desert country.
http://www.google.com/publicdata/explore?ds=d5bncppjof8f9_&met_y=sp_pop_totl&idim=country:TCD&dl=en&hl=en&q=chad+population
One wonders how many more trees there would be if they had not been chopped down for firewood if the people in the area had access to reasonably priced fossil fuels for their cooking and other energy needs.
According to the ice cores, famously ‘misread’ by, Al Gore, as proving increased atmospheric CO2 levels were followed by increases in global temperatures, actually show, and this was conceded in the British High Court by the makers of ,An Inconvenient Truth, and government scientists, that the reverse was true.
The ice-cores demonstrate that rising global temperatures are followed eight-hundred to two-thousand-years later, by identical rises in the levels of CO2.
Rising global temperatures gradually, over hundreds of years, warm the oceans causing them to create more CO2,
It is a matter of historical record that climate change is a natural phenomenon and extremes such as ice-ages occur every twelve-thousand-years or so, and unless dinosaurs burned fossil fuels by driving cars, or flying aircraft, according to the insane greenhouse gas theory, these known events could not possibly have occurred.
Reality beats ‘adjusted data fed, climate computer models, hands down.
“We need to get some broad based support, to capture the public’s imagination…
So we have to offer up scary scenarios, make simplified, dramatic statements
and make little mention of any doubts… Each of us has to decide what the right balance
is between being effective and being honest.”
– Prof. Stephen Schneider, Stanford Professor of Climatology,lead author of many IPCC reports
“We’ve got to ride this global warming issue. Even if the theory of global warming is wrong,
we will be doing the right thing in terms of economic and environmental policy.”
– Timothy Wirth, President of the UN Foundation
“No matter if the science of global warming is all phony… climate change provides the greatest opportunity to bring about justice and equality in the world.”
– Christine Stewart, former Canadian Minister of the Environment
“The data doesn’t matter. We’re not basing our recommendations on the data. We’re basing them on the climate models.”
– Prof. Chris Folland, Hadley Centre for Climate Prediction and Research
“The models are convenient fictions that provide something very useful.”
– Dr David Frame, climate modeler, Oxford University
“I believe it is appropriate to have an ‘over-representation’ of the facts on how dangerous it is, as a predicate for opening up the audience.”
– Al Gore, Climate Change activist
“It doesn’t matter what is true, it only matters what people believe is true.”
– Paul Watson, co-founder of Greenpeace.
And they wonder why we do not believe them!
Gonzalez is the “Climate Change” scientist for the National Park Service. Let’s hope the climate doesn’t stop changing, otherwise he is out of a job.
Similarly, he does not study climate records, but “Climate Change” records. I suggest his brief must be predetermined. What other result can one expect.
Does large parts of the world suffer from the climate changing? Of course it does – take Canada for instance – 18,000 years ago Canada was covered under a two mile thick ice sheet. There was no Canada back then. Before that Arctic Canada has trees similar to those presently found in southern China. Dinosaurs roamed the region. Even before that North America itself was split apart by the Great Western Inland Sea – today those of us here in the oil sands dig up marine dinosaurs that once made the Great Western Inland Sea their home. More recently the North American west suffered through the dirty thirties – and the west was referred to as the Dust Bowl.
That the world has experienced climate shifts is nothing new to any reasonably intelligent human being with one brain cell still functioning – and the last time I checked Africa was no exception to the rule of change. The single largest reason for planetary change has been plate tectonics – and we’ve discussed this many time here and in the comment section. However, what is radically missing from the discussion with reports such as this one, especially from so called scientists, is the historical changing earth put into context of these studies. It is disingenuous of these “scientists” if one can even call them scientists to lump every study into their pet Global Warming fantasy – especially when this planet has a long history of change. To me the Global Warming cartel has done more damage to science than every religion combined has ever done. And that’s saying a whole lot.
As others here have commented, I wonder if Sahel, et al. considered this view, which suggests that climate change in this area is due to loss of trees, and not vice versa:
Excerpt:
“Scholes described the typical pattern of deforestation in Africa: loggers come into a forest, they chop the large trees and take out the valuable timber, then charcoal manufacturers remove a large proportion of the remaining trees, and then low-input, low-output agriculture arrives, which after a few cycles leaves the land degraded and of little value to anyone.”
Source:
http://allafrica.com/stories/201112051950.html
Change will lead to both good and bad. I only seem to read only bad when climate change is involved. I therefore conclude that climate change is being misrepresented.
Change will lead to both good and bad. I only seem to read only bad when climate change is involved.
This is a very common misconception. It is very well known by scientists (yes, even the climatologists) that some regions will experience a positive effect due to climate change. For example, northern regions of Europe may be able to produce wine in the near future if temps continue to rise. There is in fact no problem with the idea of climate change itself. The Earth’s climate has changed many times in the past. The problem is with rapid climate change (within a century or less) on an Earth with a human population of around 7 billion. Such a situation has the potential for much upheaval and it is this uncertainty for the future that is problematic.
More to read:
Can’t See the Forest for the Trees
http://magazine.uchicago.edu/0810/features/the_forest.shtml
Looking to the Sahel for Lessons in Pushing Back Deserts
http://ipsnews.net/news.asp?idnews=105491
http://africa-regreening.blogspot.com/
I think you’ve got it.
The pattern is simple as I understand it.
WARMER = WETTER
The Sahel has been greening in recent decades, compared with earlier in the last century. But what it will do now is another matter.
The image of the tree at the header has had all of it’s bark removed, which has two possible sources; people in the Sahel region use bark as kindling for cooking fires. They also raise goats as a primary food source, and goats eat bark, many studies have suggested the introduction of the goat into North Africa as one of the primary causes of deforestation.