Chronic 2000-2004 drought, worst in 800 years, may be the 'new normal': study

Jul 29, 2012
Pinyon pine forests near Los Alamos, N.M., had already begun to turn brown from drought stress in the image at left, in 2002, and another photo taken in 2004 from the same vantage point, at right, show them largely grey and dead. (Photo by Craig Allen, U.S. Geological Survey)

The chronic drought that hit western North America from 2000 to 2004 left dying forests and depleted river basins in its wake and was the strongest in 800 years, scientists have concluded, but they say those conditions will become the "new normal" for most of the coming century.

Such climatic extremes have increased as a result of global warming, a group of 10 researchers reported today in Nature Geoscience. And as bad as conditions were during the 2000-04 drought, they may eventually be seen as the good old days.

and precipitation projections indicate this period will actually be closer to the "wet end" of a drier hydroclimate during the last half of the 21st century, scientists said.

Aside from its impact on forests, crops, rivers and water tables, the drought also cut by an average of 51 percent in a massive region of the western United States, Canada and Mexico, although some areas were hit much harder than others. As vegetation withered, this released more carbon dioxide into the atmosphere, with the effect of amplifying global warming.

"Climatic extremes such as this will cause more large-scale droughts and forest mortality, and the ability of vegetation to sequester carbon is going to decline," said Beverly Law, a co-author of the study, professor of and science at Oregon State University, and former science director of AmeriFlux, an ecosystem observation network.

"During this drought, carbon sequestration from this region was reduced by half," Law said. "That's a huge drop. And if don't come down, the future will be even worse."

This research was supported by the National Science Foundation, NASA, U.S. Department of Energy, and other agencies. The lead author was Christopher Schwalm at Northern Arizona University. Other collaborators were from the University of Colorado, University of California at Berkeley, University of British Columbia, San Diego State University, and other institutions.

It's not clear whether or not the current drought in the Midwest, now being called one of the worst since the Dust Bowl, is related to these same forces, Law said. This study did not address that, and there are some climate mechanisms in western North America that affect that region more than other parts of the country.

But in the West, this multi-year drought was unlike anything seen in many centuries, based on tree ring data. The last two periods with drought events of similar severity were in the Middle Ages, from 977-981 and 1146-1151. The 2000-04 drought affected precipitation, soil moisture, river levels, crops, forests and grasslands.

Ordinarily, Law said, the land sink in North America is able to sequester the equivalent of about 30 percent of the carbon emitted into the atmosphere by the use of fossil fuels in the same region. However, based on projected changes in precipitation and drought severity, scientists said that this carbon sink, at least in western North America, could disappear by the end of the century.

"Areas that are already dry in the West are expected to get drier," Law said. "We expect more extremes. And it's these extreme periods that can really cause ecosystem damage, lead to climate-induced mortality of forests, and may cause some areas to convert from forest into shrublands or grassland."

During the 2000-04 drought, runoff in the upper Colorado River basin was cut in half. Crop productivity in much of the West fell 5 percent. The productivity of forests and grasslands declined, along with snowpacks. Evapotranspiration decreased the most in evergreen needleleaf forests, about 33 percent.

The effects are driven by human-caused increases in temperature, with associated lower soil moisture and decreased runoff in all major water basins of the western U.S., researchers said in the study.

Although regional precipitations patterns are difficult to forecast, researchers in this report said that climate models are underestimating the extent and severity of drought, compared to actual observations. They say the situation will continue to worsen, and that 80 of the 95 years from 2006 to 2100 will have precipitation levels as low as, or lower than, this "turn of the century" drought from 2000-04.

"Towards the latter half of the 21st century the precipitation regime associated with the turn of the century will represent an outlier of extreme wetness," the scientists wrote in this study.

These long-term trends are consistent with a 21st century "megadrought," they said.

Explore further: EPA staff says agency needs to be tough on smog

More information: DOI: 10.1038/ngeo1529

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NotParker
2.1 / 5 (18) Jul 29, 2012
"The last two periods with drought events of similar severity were in the Middle Ages, from 977-981 and 1146-1151."

Not a lot of SUV's on the road ....

Try to remember the AGW cult said Australia was going to be in permanent drought and they spent a fortune on desalination plants. Well, the rains came and the dams are close to being full.
Torbjorn_Larsson_OM
4.7 / 5 (12) Jul 29, 2012
This is about the same time frame as the ~ 100 % area Greenland ice melt. When you go to the melt record of the ice cores, it is clustered, so the initial "once every 150 years" is skewed. It was the worst in 800 years too...

@ NotParker:

You can't have a "cult" on science based on accepting it when it works. And AGW is the current climate theory of all climate scientists.

These are regional effects. Even if you did not give a reference, I found a source.

"IT MAY be time to stop describing south-eastern Australia as gripped by drought and instead accept the extreme dry as permanent, one of the nation's most senior weather experts warned yesterday.

"Perhaps we should call it our new climate," said the Bureau of Meteorology's head of climate analysis, David Jones.

He was speaking after the release of statistics showing that last year was the hottest on record in NSW, Victoria, South Australia and the ACT."

""There is absolutely no debate that Australia is warming," said Dr Jones.
Torbjorn_Larsson_OM
5 / 5 (8) Jul 29, 2012
[cont]

"There is a debate in the climate community, after close to 12 years of drought, whether this is something permanent. Certainly, in terms of temperature, that seems to be our reality, and that there is no turning back."

http://www.smh.co...473.html

No definite claim as you imply, but a "debate in the climate community". Also, the rest of the article make it clear that the drought is not relative water magazines but relative the usual rain period.

The bottom line: "There is absolutely no debate that Australia is warming,".
kochevnik
3.2 / 5 (11) Jul 29, 2012
USA is so screwed intellectually, financially and ecologically.
Osiris1
3.3 / 5 (4) Jul 29, 2012
Dams and the impounded water can alter climate in an of themselves. All one needs to do is look at the history of climate in Oklahoma as the state and national government built dam after dam in OK and the resultant lakes led to the raising of the state's average relative humidity.
TheGhostofOtto1923
3 / 5 (12) Jul 29, 2012
Uh oh

"Global warming not only is real, but "humans are almost entirely the cause," a self-described former climate change skeptic has declared.
"Call me a converted skeptic," Richard A. Muller, University of California, Berkeley physics professor said in an opinion piece posted online Saturday in The New York Times."

It takes a big man to admit he was wrong. So I hear.
thermodynamics
3.8 / 5 (10) Jul 29, 2012
SpookyOtto said: "It takes a big man to admit he was wrong. So I hear."

That is right and is part of the reason you will never hear NotParker saying he was wrong. It just won't happen - even though he is wrong when he denies AGW. That was a remarkable paper that the Berkeley Earth group put out under Muller. He has really improved my view of his integrity when he has changed his mind based on evidence. He was one of the group that was skeptical of station data based on his view of the "heat island effect." He analyzed the data and realized his initial view was wrong and he admitted it. That shows the strength and integrity of a real scientist. I can't wait to hear from the denialists on the new Berkeley study. They used to praise Muller when he was a skeptic but I bet he is not praised now.
Telekinetic
2.3 / 5 (3) Jul 29, 2012
It is high time for rain making technology to be investigated, developed, and implemented. I'm not talking about cloud seeding or rain dances. It has to be approached as a technical problem that has a solution.
AgingDemon
4.3 / 5 (6) Jul 30, 2012
"The last two periods with drought events of similar severity were in the Middle Ages, from 977-981 and 1146-1151."

Not a lot of SUV's on the road ....

Try to remember the AGW cult said Australia was going to be in permanent drought and they spent a fortune on desalination plants. Well, the rains came and the dams are close to being full.


http://www.youtub...re=share

debunked that argument for you.
Vendicar_Decarian
4.1 / 5 (10) Jul 30, 2012
The Conversion of a Climate-Change Skeptic

http://www.nytime...nted=all
thermodynamics
4.3 / 5 (6) Jul 30, 2012
Great sites posted by both VD and AgingDemon. For those of you who have not looked at the sites linked in by two in the comments above, they are both worth the time it takes to go through them. Of course NP won't take the time to educate himself a little. With the new analysis from the Berkeley Earth group (Muller) there is not a lot of wiggle room for the deniers. The article in the New York Times that VD pointed out will give you the background you need to know how Muller worked to change his own perspective. Great article and well worth reading.
Birger
5 / 5 (4) Jul 30, 2012
"not a lot of wiggle room for the deniers" Irrelevant: True Deniers put "truthiness" (what they "know" to be true) before mere "truth".

The photo of the dead pine forests might finally bring home the lesson that the cost of doing nothing far exceeds the cost of doing *something*.
rubberman
4.4 / 5 (7) Jul 30, 2012
Excellent link Vendi! Did any of you click on the link inside Vendi's link to Berkeley.org where they posted the results of the entire study? Oddly enough the last 50 year portion of each graph looks like a...wait for it...HOCKEY STICK!

Could be a coincidence....
TheGhostofOtto1923
3.2 / 5 (9) Jul 30, 2012
It is high time for rain making technology to be investigated, developed, and implemented. I'm not talking about cloud seeding or rain dances. It has to be approached as a technical problem that has a solution.
First you need moisture in the atmosphere to make rain out of. As usual this is a job for engineers.
http://www.reuter...20120606
http://www.geoeng...drought/
Telekinetic
5 / 5 (2) Jul 30, 2012
The engineers, by spraying particulates into the atmosphere, are screwing up any chance of rainfall, according to your reference. This is not a job for engineers, but a job for those with a completely new approach. Your faith in experts is misguided since they've only wreaked havoc on the environment. The solution requires an understanding of the energetic conditions surrounding weather, and it's not in your engineers' books or experience.
NotParker
1.4 / 5 (9) Jul 30, 2012
Australia's Drought ended. As previous ones ended.

"One of the first recorded was in 1803 when there were severe crop failures in New South Wales.

Another, devastating nationwide drought followed in 1902, just after Australia became a federation.

During that one, the total sheep population halved, from just over 100 million to about 50 million.

It wasn't until 1927 sheep numbers recovered.

One of the longest dry periods lasted through the Second World War, from 1937 to 1947, with eastern Australia again the worst affected.

Other bad droughts followed at an interval of about one every decade.

And the pattern has been repeated into the 21st Century."

http://www.bbc.co...17887572
rubberman
5 / 5 (5) Jul 31, 2012
"Australia's Drought ended. As previous ones ended."- PT

Just so I follow where your going with that Australian history lesson - You're saying that you disagree with the article because droughts in other parts of the world end? Or are you saying that Australia is in a permanent drought cycle? Or that you like sheep and are sad that so many perished?
NotParker
2.1 / 5 (8) Jul 31, 2012
"Australia's Drought ended. As previous ones ended."- PT

Just so I follow where your going with that Australian history lesson - You're saying that you disagree with the article because droughts in other parts of the world end? Or are you saying that Australia is in a permanent drought cycle? Or that you like sheep and are sad that so many perished?


Droughts are cyclic in the USA and Australia.

The paper borders on fraudulent for not mentioning drought cycles.

The AGW cult leader in Australia and his disciples made claims that Australia was now in a permanent drought. That was not true.

However, if you believe in magic treemometers, you can consider that humans did not cause the droughts 1000 years ago, therefore for a person to claim they are man-made now (without any evidence) borders on fraud.
rubberman
4.3 / 5 (6) Jul 31, 2012
"Droughts are cyclic in the USA and Australia."

This is true. National geographic published a paper in 2005 indicating a 160 year cycle had been discovered. An AGW skeptic website showed one with a 60 year cycle (this one was funny because it predicted a return to "normal" conditions after the last major drought in 2002). The current drought isn't part of any established cycle. That is the reason for speculation on causation.

"The AGW cult leader in Australia and his disciples made claims that Australia was now in a permanent drought. That was not true."

Do you have a quote for this from said AGW cult leader? If so then I agree with you that it is a rediculous statement given the precipitation Australia had last year, alot of places had more rain than the statistical norm.

"The paper borders on fraudulent for not mentioning drought cycles".
Only if the drought is part of an established cycle, this one isn't.

NotParker
2.1 / 5 (7) Jul 31, 2012
""We've seen historic droughts in some cases five to seven decades long, with severity along the lines of [the Dust Bowl of] the 1930s," he said, noting that he expects such droughts to return. "They have occurred for the last several thousand years, so there's no reason to expect anything different.""

http://news.natio...t_2.html

Australia quotes:

Flannery: "so even the rain that falls isnt actually going to fill our dams and river systems "

http://blogs.news...nt_rain/
NotParker
1.7 / 5 (6) Jul 31, 2012
The current drought isn't part of any established cycle. That is the reason for speculation on causation.


I think if you look at the PDSI graphed over time you might conclude the rainy 70s/80s/90s were unusual.

http://www.ncdc.n...mp;div=0

NotParker
2.1 / 5 (7) Jul 31, 2012
The current drought isn't part of any established cycle. That is the reason for speculation on causation.


If you look at USA precipitation, the 90s were the unusual wet decade, with the 80s and 70s being less wet, but still wetter that every previous decade.

That period coincides with the positive PDO. Which has now gone negative.

The US has for a short period returned to to pre-1970s rainfall amounts.

If it last for the next 30 years it will be a problem. But CO2 had nothing to do with it.

Dry used to be normal.

http://www.ncdc.n...mp;div=0
Howhot
3.5 / 5 (8) Jul 31, 2012
Are you having a hard day NP? Seem like everyone is ganging up against-ya. Its not the fact that there are droughts this year that is unusual. It's the area that it covers that is bad, right across the bread basket of the US. The global temperature extremes are just compounding the damage done to the effected flora, ecosystems and landscape.

There is no doubt, just like AGW has created massive weather extremes, AGW has had very active hand in the current severity of drought conditions across the central USA. Similarly with the flash melt of Greenland this year, or the peat bog fires of Russia last year.

Vendicar_Decarian
5 / 5 (4) Jul 31, 2012
Survey: "Climate Skeptics" More Likely to Embrace "Free Market" Ideology, Conspiracy Theories

http://www.common...12/07/27

"The link between endorsing conspiracy theories and rejecting climate science facts suggests that it is the libertarian instinct to stick two fingers up at the mainstream whatever the issue that is important," writes The Guardian's James Corner. "Because a radical libertarian streak is the hallmark of free-market economics, and because free market views are popular on the political right, this is where climate change skepticism is most likely to be found."
NotParker
2.1 / 5 (7) Jul 31, 2012
Are you having a hard day NP? Seem like everyone is ganging up against-ya. Its not the fact that there are droughts this year that is unusual. It's the area that it covers that is bad, right across the bread basket of the US.


Droughts happen. Even in farm country. The link I proved to the NOAA shows that the 90s were unusually wet.

Many AGW cult members like you have short memories.

I looked at the BEST data just released.

contiguous-united-states
Highest TMAX 5 year averages
The current 5 year period is ranked No. 6 for contiguous-united-states
===========================================================
1 2001 - 2006 0.64
2 1996 - 2001 0.61
3 1951 - 1956 0.56
4 1986 - 1991 0.5
5 1931 - 1936 0.46
6 2006 - 2011 0.33
7 1936 - 1941 0.24
8 1941 - 1946 0.12
9 1906 - 1911 0.04
NotParker
1.7 / 5 (6) Jul 31, 2012
200-2004 wasn't that bad a drought according to the NOAA PDSI

http://www.ncdc.n...mp;div=0

The 30s and 50s were worse.
NotParker
1 / 5 (5) Jul 31, 2012
Survey: "Climate Skeptics" More Likely to Embrace "Free Market" Ideology, Conspiracy Theories


Oh oh.

"Visitors to climate blogs voluntarily completed an online questionnaire between August and October 2010"

Nobody ever lies on an online survey .... ha ha ha ha.

VD, you've been punked again.

Vendicar_Decarian
3.3 / 5 (7) Aug 01, 2012
ParkerTard seems to be very content at the fact that the U.S. grain belt is reverting to desert and that Americans will soon not be able to feed themselves.

This is the future that Free Market Republicans have always had in store for America.
Vendicar_Decarian
3.7 / 5 (6) Aug 01, 2012
"The 30s and 50s were worse." - ParkerTard

During the 1930's dust bowl, the PDSI (2 month average) was .95 per year on average.

During the last decade it has been 0.07

During the 1950's it was -0.84

So the current decade is significantly dryer than the 1930's but not as yet dry as the 1950's.

But as the desertification of the U.S. grain belt continues, it will only get dryer and dryer.
Vendicar_Decarian
3.9 / 5 (7) Aug 01, 2012
Yup. ParkerTard is right. It's all a conspiracy against the denialists.

"VD, you've been punked again." - ParkerTard

He is mentally diseased of course.
ubavontuba
2.1 / 5 (7) Aug 01, 2012
Chronic 2000-2004 drought, worst in 800 years, may be the 'new normal': study
Okay, it's oficial. Climate scientists have rested their reputation on this prediction (again). This time, when it fails to hold true, will they openly admit their error?

Hardly.

I can see the headlines now now...

"Cool Wet Winter and Pleasantly Mild Summers Are Caused By AGW, Scientsist Say"

What a pack of opportunists and liars.

"Drought is a normal, recurring feature of climate; it occurs in virtually all climatic regimes. ...It is rare for drought not to occur somewhere in North America each year. ...The largest area affected by drought occurred in 1934, when more than 65% of the nation experienced severe or extreme drought. Other significant drought episodes, ...occurred in the 1890s, 1910, 1925-26, 1931-40, mid-1950s, 1964-65, 1976-77, 1983, 1988-92, 1994, and 1996.

http://www.ametso...ht2.html
Vendicar_Decarian
3.9 / 5 (7) Aug 01, 2012
NotParker
2.7 / 5 (7) Aug 01, 2012
"The 30s and 50s were worse." - ParkerTard

During the 1930's dust bowl, the PDSI (2 month average) was .95 per year on average.


NOAA says PDSI was:

1930,-1.88
1931,-3.93
1932,0.09
1933,-0.91
1934,-6.62
1935,-3.05
1936,-3.22
1937,-2.02
1938,0.01
1939,-2.74
1940,-4.07

http://www.ncdc.n...mp;div=0
Howhot
5 / 5 (3) Aug 01, 2012
Welcome to the New Normal!

NOAA also says "U.S. experiences warm and dry June; drought expands to 56 percent of the Lower 48". They also add
"June global temperatures fourth highest on record"!! right on the front of their website.

NP, by the way have you looked at the trend lines the 5yr and 10yr running averages of the data your sighting. They look like a planet that has the CO2 fever and its getting worst just as a green house gas atmosphere would trap and build heat.

I don't see how you deniers can be so blind to the continual weather events, temperature rise, the exacerbated spring flooding and summer droughts. And it's GLOBAL!

NotParker
1.8 / 5 (5) Aug 02, 2012
Welcome to the New Normal!


The old normal was 11 year droughts. The current drought is about 1 year old.

Quit lying.
Howhot
5 / 5 (2) Aug 04, 2012
I think its worth listening to Dr Hansan on this. He talks about this current drought and it's relationship to AGW.

http://www.washin...ory.html

If that doesn't get you deniers pesky neurons firing, I don't know what will.
NotParker
1 / 5 (2) Aug 04, 2012
I think its worth listening to Dr Hansan on this. He talks about this current drought and it's relationship to AGW.

http://www.washin...ory.html

If that doesn't get you deniers pesky neurons firing, I don't know what will.


Are you saying less CO2 caused longer, deeper droughts?

"On a broad scale, the 1980s and 1990s were characterized by unusual wetness with short periods of extensive droughts, the 1930s and 1950s were characterized by prolonged periods of extensive droughts with little wetness, and the first decade of the 2000s saw extensive drought and extensive wetness"

http://www.ncdc.n...drought/

Howhot
not rated yet Aug 06, 2012
Are you saying less CO2 caused longer, deeper droughts?


No NP, I thought that was your position. No, I take the position that MORE CO2 is causing longer, and deeper droughts! Is that clear enough?