Trees may be better rain gauges than they are thermometers. From a press release of:
Killer’ Southeast Drought Low on Scale, Says Study
Others Were Far Worse; Population, Planning Are the Real Problems
Lake Allatoona, Ga., November 2007
A 2005-2007 dry spell in the southeastern United States destroyed billions of dollars of crops, drained municipal reservoirs and sparked legal wars among a half-dozen states—but the havoc came not from exceptional dryness but booming population and bad planning, says a new study. Researchers from Columbia University’s Lamont-Doherty Earth Observatory defied conventional wisdom about the drought by showing that it was mild compared to many others, and in fact no worse than one just a decade ago. According to the study, climate change has so far played no detectable role in the frequency or severity of droughts in the region, and its future effects there are uncertain; but droughts there are essentially unpredictable, and could strike again at any time. The study appears in the October edition of the Journal of Climate.
“The drought that caused so much trouble was pathetically normal and short, far less than what the climate system is capable of generating,” said lead author Richard Seager, a climate modeler at Lamont. “People were saying that this was a 100-year drought, but it was pretty run-of-the-mill. The problem is, in the last 10 years population has grown phenomenally, and hardly anyone, including the politicians, has been paying any attention.”
Region wide, the drought ran from late 2005 to winter 2007-2008, though many areas in the south were still dry until last week, when the weather turned conclusively, and flooding killed at least eight people. During the height of the dry period, Atlanta’s main reservoir sank more than 14 feet, usage restrictions were declared in many areas, and states became embroiled in lawsuits among themselves and with the federal government over use of water in rivers and reservoirs.
Seager and his coauthors Alexandrina Tzanova and Jennifer Nakamura put the period in context by comparing it with instrumental weather records from the last century and studies of tree-growth rings, which vary according to rainfall, for the last 1,000 years. These records show that far more severe, extended region-wide events came in 1555-1574, 1798-1826 and 1834-1861, with certain areas suffering beyond those times. The 1500s drought, which ran into the 1600s in some areas, has been linked by other studies to the destruction of early Spanish and English New World colonies, including Jamestown, Va., where 80 percent of settlers died in a short time. The 20th century turned out relatively wet, but the study showed that even a 1998-2002 drought was worse than that in 2005-2007.
The factor that has changed in the meantime is population. In 1990, Georgia, which uses a quarter of the region’s water, had 6.5 million people. By 2007, there were 9.5 million—up almost 50 percent in 17 years. The population is still ascending, driven largely by migration. However, little has been done to increase water storage or reduce consumption. There has been increased sewage discharge near water supplies, and vast tracts of land have been covered with impermeable roofs, roads and parking lots, which drain rainfall away rapidly instead of storing it.
Previous studies by Seager and colleagues have shown that droughts in the American Southwest and Great Plains states are controlled by cyclic changes in tropical Pacific Ocean sea-surface temperatures –the El Niño-Southern Oscillation cycle. This means that dry weather, which goes along with the cold phase of the cycle, can be predicted to some extent. However, in the current study, the scientists found only a weak correlation between Southeast weather and the tropical Pacific. Instead, says Seager, dry spells appear to be generated by random changes in regional atmospheric circulation. This means weather could dry up at any time.
Seager’s studies also suggest that manmade warming is beginning to perturb precipitation patterns across the globe. As a result, he says, the Southwest may have already entered a period of long-term aridity. In contrast, global warming does not appear to have yet affected rainfall one way or the other in the Southeast. Most climate models project that higher temperatures will actually increase rainfall there—but as temperature rises, evaporation will also increase. At best, says Seager, the two effects may balance each other out; at worst, evaporation will prove stronger, and result in drier soils and reduced river flows in the long term. “Climate change should not be counted on to solve the Southeast’s water woes, and is, in fact, as likely to make things worse as it is better,” says the paper.
“It was a lot drier in the 19th century than it has been recently, but there were so few people around, it didn’t harm anyone,” said Seager. “Now, we are building big urban centers that make us vulnerable to even slight downturns.”
The Federal Emergency Management Agency estimated that national losses due to drought ran around $8 billion a year in the 1990s, but they are probably higher now. Mark Svoboda, a climatologist at the National Drought Mitigation Center at the University of Nebraska who was not involved in the research, said of the study’s results: “This should be a wake-up call. If this is not the worst case scenario, what are we going to do when the worst-case scenario arrives?”
David Stahle, a tree-ring scientist at the University of Arkansas who made the link between 1500s-1600s droughts and the struggles of early Southeast colonies, said settlers then were particularly vulnerable because they had just arrived and lacked sufficient infrastructure or backup supplies. He called the Lamont study “a bedtime story with a moral for modern times.”
“Are we returning to a period of sensitivity and danger like the colonists experienced?” said Stahle. “In a way, yes, it looks like we are.”
I know I will be dealing with this the rest of my life. What else is there? Even when they get it right they get it wrong. If the conclusion was that this was not a bad drought then why talk about climate change at all. Why speculate. And why would it get worse and not better. I have read maybe one or two articles that say as the earth warms people will benefit. How can the whole world get worse? I am tired of the negativity.
WWS,
It may not have been the droughts, as much as it was the nature of the rainfall, that stressed out the Anasazi culture. One theory I have read states that gentle rains were replaced by gully-washer thunderstorms, and the irrigation systems were wrecked, or rendered useless when the stream-bottoms eroded lower than the inflow channels to canals.
I mentioned in an earlier Briffa post that I have cut down hundreds of trees and always check the rings. In New England the rings seem to show it is the rainfall during the months from March to July, more than temperature or other factors, that encourages growth. Despite the fact there is considerable variation from tree to tree, nearly all trees show a drought that lowered reservoirs in New England in the mid-1960’s, with a series of skinny rings.
However even here there are exceptions to the rule, for some trees press the limits in terms of how much time they can stand with “wet feet.” (These trees are the sort that inhabit lowlands, and which a single family of beavers can wipe out with a single dam, which is why you can sometimes see a ten acre patch of dead trees, standing silver and barkless, while driving across New England.) These trees, growing in a flat area which is not quite too wet for trees, actually benefited from the 1960’s drought in New England, and their rings show they grew better during that drought, for their roots were under water less.
Therefore one can arrive at opposite conclusions, if one looks at tree rings in New England without paying attention to where the trees are from. An unscrupulous resercher could prove nearly anything they wanted.
I have found great pleasure studying tree rings, and feel a dedicated scientist could learn far more than I’ve learned. I would hate to see funding for such study cease. However such study must be honest, and not funded by people who have an agenda and desire certain results. Such funding, whether it be from Big Business or Big Brother, sucks all the wonder from science, and, rather than inspired by the beauty of truth, we wind up disgusted by the dishonesty of greed.
“Pamela Gray (20:59:04) :
Is “aridity” akin to “nuditity”? Can anyone tell me who coined that word?”
Year 1599, he says dryly.
http://www.etymonline.com/index.php?term=aridity
Forget about climate, just enjoy it!….but, to be sure, buy a bigger heater.
“Stephen Skinner (06:09:43) :
Only slightly OT, in as far as the region. I thought the most significant drought to hit the US in recent history was the Dust Bowl of the 1930s, which also hit Canada. I understood it to be devastating and was brought about by the farming practices of the time, although I have heard it was Climate Change also. This event is surely the bench mark for drought in North America?”
Recently on WUWT there was an article on the death of Dr. Norman Borlaug.
Anyone wanting to read what he had to say about that, the links are there.
http://wattsupwiththat.com/2009/09/13/agicultural-pioneer-and-climate-skeptic-dr-norman-borlaug/
Not quite OT – a response to piping water from the East to the West. There is new R.O. technology just announced which significantly cuts the amount of power needed to produce fresh water. Now all the folks that champion windmills have to do is get the NIMBYs to let them build massive R.O. facilities offshore in CA which are also sites for windmills.
My bet is that the NIMBYs would rather die of thirst.
Aron (06:14:54) :
Bark thickness isn’t involved in tree rings. The rings are growth variations laid down inside the cambium, while the bark is produced outside the cambium.
Crosspatch and Michael: “Fallen Angels” is an example of contemporary science fiction that is timely, prophetic and satirical.
wsbriggs: re Desalinated water in California.
We are building one plant, near San Diego, to produce 50 million gallons per day.
The power required is a major operating cost, but the cost of carbon credits required to keep the plant running under cap and trade will likely make this the last such plant ever built in California.
NEWTAP is in keeping with California’s penchant for importing necessities such as electric power, automobiles, and water. As the state’s idiotic laws continue to choke the economy, more and more businesses close their doors and flee the state to more friendly environs.
“Steve McIntyre’s profession is a statistician, his hobby is climatology.”
There is no profession in the world more important than statistics to this subject. All of the results and theories stand on top of statistics.
I am stunned at the lack of statistical training on the part of these “climatologists”.
Nuclear makes a great power source for desalinization. In fact, it could probably be integrated into the cooling system.
Oh, and the link I gave above (at 01:23:19) is the CA article I thought I had read several years ago with the information on the Sierra lakes and prolonged drought in California.
crosspatch:
Why would anyone want to build a new nuclear power plant at 30 to 40 cents per kWh to run a desalination plant? What would be the required sales price for the desalinated water in that case? Can anyone afford such expensive water?
Or are you proposing to increase the condensing pressure on existing nuclear power plants, thus producing much less power from each plant, in order to increase the temperature of the steam so it can provide energy to thermal desalination? How would the reduced power be replaced, and provided to the grid?
wsbriggs (09:07:07)
Do you have a link to that energy saving Reverse Osmosis technology that you mentioned?
Nuclear electricity costs 30 to 40 c/Kw-Hr? Try about a tenth of that although with enough lawyers I’m sure you can make anything more expensive than necessary.
Nukes are baseload power although I’ve seen plans for peak load nukes as a result of work done on nuclear aircraft propulsion in the 1950s and nuclear thermal rockets clearly don’t take hours to bring up to power.
So build more and bigger nukes so that you can cover base + peak power requirements and run the desalination RO plants when not all the electricity is required to run the grid. The water is easily storable to provide system buffers and the desalinated water is unlikely to be the sole source of water anyway.
This system would be perfect for Australia with large cities all needing extra water all on the coast and a lunatic government about to cripple our economy with an emissions trading scheme while something like 80+ % of our electricity is presently generated by burning coal and the same government is resolute against nuclear power. This in a country with around 40% of the world’s easily recoverable uranium and lots of GAFA to store any waste in. Did I say lunatic?
* GAFA – Great Australian F… All
“Why would anyone want to build a new nuclear power plant at 30 to 40 cents per kWh to run a desalination plant?”
On what planet does nuclear power cost 30 to 40 cents per kWh?
Electricity Production Cost by Fuel Type (2008)
* Nuclear: 1.87 cents per kWh
* Coal: 2.75 cents per kWh
* Natural gas: 8.09 cents per kWh
* Oil: 17.26 cents per kilowatt-hour (kWh)
And nuclear power costs drop even more if you co-locate a fast neutron reactor and processing plant on the same site. This is because it allows spent fuel to be re-used and also eliminates the need for the expensive enrichment process. Natural uranium is exposed to the neutron stream where it is converted direction into fuel via transmutation. This means things such as “depleted” uranium can be used for fuel.
This also eliminates the long-term storage problem for spent fuel and eliminates the issue of transporting fuel over the transportation system. Once fuel enters the site, it never leaves. What waste is produced decays in only a few hundred years. We know how to build structures that last a few hundred years.
I would point you to learning about the AP1000 plant from Westinghouse. It is the safest plant ever built. You can shut off the primary cooling system and all external electrical supply and the plant will maintain cooling for up to two weeks without any intervention using only natural convection, evaporation, and gravity. With the application of external cooling water to the outside of the containment dome, it can be rendered safe indefinitely.
crosspatch,
You must have missed all the fireworks on WUWT a few weeks ago where this topic of nuclear power was discussed.
You might want to recognize a few facts about the US nuclear power industry’s abysmal record of building power plants on schedule and on-budget. Cost overruns of 5 or even 6 times the original estimate were the rule, not the exception. Case in point is South Texas Nuclear Project, original cost estimate $900 million, final cost $5.5 billion, plus many years behind schedule. The much-touted French Areva reactor design is taking the typical route at the plant in Finland, where the project is many billions of Euros over budget, and so far behind schedule they no longer will make even an estimate of the completion date.
Nothing has changed in this industry, except the fools who want to build these things. Now South Texas Nuclear Project is wanting to expand the site, using two Japanese reactors to double the capacity. The cost estimate this time is for $13 billion – but it will easily be $22 to $25 billion.
Don’t take my word for it. See a nuclear project expert’s writings, Craig Severance.
As to the comparative costs you cited above, those appear to be merely variable costs of production, and do not account for capital charges. That is a bit like crowing that one’s car costs only 10 cents per mile to drive, and counting only the cost of gasoline. The $1200 per month car payment is conveniently ignored. In the real world, the utility must charge the consumers for enough money to pay off the money borrowed to build the plant, and the equity owners in the plant.
In any event, even if San Antonio buys into the STNP expansion, the cost overruns and lengthy delays are inevitable. It will be the last nuclear plant ever built in the USA, and the costomers in its service area will pay dearly for their power. That is a good thing in one respect, because it will provide strong incentive to use solar, wind, and local mini-gas turbines as customers go off the grid. That is a bad thing, though, for the poor and those on fixed incomes who have no options but to pay the outrageous increased power prices to the utility.
See my article on Nuclear Nuts, at http://sowellslawblog.blogspot.com/2009/04/nuclear-nuts.html
Mike Borgelt,
Well, I am a lawyer, and my skin is pretty thick. We bring lawsuits to force nuclear power plant builders to follow the law, build a safe plant, and comply with all environmental and regulatory requirements. We do the same with natural gas fired power plants, wind-turbine power systems, solar-powered systems, and coal-fired power plants. If you would like to change the regulations on nuclear power plant design and construction, and the environmental requirements, please go to it.
The nuclear advocates in this country love to whine that the lawyers increased the cost of the existing nuclear power plants. At the same time they crow about their perfect safety record – when in reality that record has yet to be written to account for spent fuel disposal or reprocessing, and radioactive waste disposal along with plant demolition. It is only because the lawyers forced them to build the plants to code and to regulations that the safety record is as good as it has been thus far.
crosspatch, I’m with you. Near as I can tell Roger is a devout anti – nuke.
I kind of like this one the most:
http://www.nvwra.org/docs/journal/vol_2_no_1/jnwra_2_article3_kleppe.pdf
That’s the Nevada Water Resources Association… they care.
ABSTRACT
The author of this paper has discovered large trees rooted at a depth of 36.5 m (120’) below the existing surface level of Fallen Leaf Lake. Fallen Leaf is one of the major watershed areas for Lake Tahoe. Some of these trees measure over 30 m (98’) tall with a circumference of over 4.5 m (15’), which is an indication that they were over two hundred years in age when they died. The significance of this discovery is the fact that for these trees to be rooted below the surface of the lake, the lake must have been down at least 36.5 m for over two hundred years. This would indicate that a “mega drought” had occurred, since several of these trees have been carbon dated to have “drowned” in 1215 A.D. ± 40 years. This would indicate that the drought persisted during the medieval period 850-1150 A.D., and was followed by an extremely wet period that brought the lake level back up high enough to drown the trees. There are also signs on these trees that another severe drought occurred sometime later, but did not persist for as long as the first one.
I added the bolding…
The L.A. Times view:
http://articles.latimes.com/1994-06-16/news/mn-4748_1_tree-ring-research
A study of the stumps of ancient trees that once grew from stream beds and lake bottoms in the Sierra Nevada has turned up new evidence that droughts in California can last 100 years or more, far longer than the state’s official estimates.
In this week’s issue of the British journal Nature, a Cal State Hayward professor writes that submerged stumps in Mono Lake, Tenaya Lake in Yosemite National Park, the West Walker River in the northern Sierra and Osgood Swamp near Lake Tahoe are relics of trees that grew on land that was uncovered when droughts reduced water levels by up to 60 feet.
Which is how you can get a tree growing full sized on what is now a lake bed…
No pretty pictures, but a decent write up with references:
http://www.planetspatula.com/holocene-drought.html
This link has a chronology of the last 2000 years of drought in the west:
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6VGS-4P2J050-C&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&_docanchor=&view=c&_searchStrId=1033081314&_rerunOrigin=google&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=cfa3df1b47252c0e5bb5dc744d47ad2d
More on the Megadroughts issue:
This one does a nice job of tying it to the end of the Maya:
http://sites.google.com/site/medievalwarmperiod/Home/drought-and-the-collapse-of-mayan-civilisation
And with more references that you could ever want:
http://sites.google.com/site/medievalwarmperiod/Home/drought-floods-famine-and-central-and-south-america/sources
and it cites the original work by Dr. Stine.
Interesting if a bit unglamorous:
http://sfbay.wr.usgs.gov/publications/pdf/dettinger_2001_droughts.pdf
tallbloke (05:58:19) : explain to me how it can be that we have one group of paleodendroclimatologists who believe trees measure temperature, and another who believe trees measure precipitation,
Plants are subject to the principle that the least available resource limits their growth. So if a tree is short of water, water will make it grow more. Too cold? Heat increases the growth. Not enough Nitrogen? Bear Poo to the rescue! (Yes, salmon runs eaten by bears doing what bears do in the woods is a major or the major source of Nitrogen to the forests. Salmon fishing and bear reductions also are measure by tree rings… )
how do they separate the supposed temperature signal from the supposed precipitation signal in tree ring widths?
Well, ya know, that’s gonna be a might tough… And don’t forget you also need to map the bear population and the salmon run sizes… AND CO2 concentrations… AND any volcanic ash fertilization… AND any shading of one tree by another (and when which fell down)… AND you need to know if any other nutrient was limiting to growth so you better have a complete soil mineral concentration plot over the entire life of the tree… otherwise you are just assuming that nothing changed when maybe a bit of flash flood washed some bird potash deposits down the hill.
Or do they believe that some trees are good thermometers and others are good precipitation guages? How do they tell the difference. And if trees are both thermometers and precipitation guages, how do they assign relative values to each trait?
Well, each person assigns the growth to the thing that they are studying. If they didn’t do that, then they would not get a paper to write or they would need to bring in some other person as co-author, and who needs that?…
IMHO, it’s a bit of a broken science. Heck, you can look at a well managed farmers field and get all the way from 8 foot corn to 2 foot runts or bare dirt in the same field with folks trying to manage it all to be the same. I’ve just got to think it will be worse in a wild tree population…
Are those underwater trees aqua firs?