Climate scientists reconsider the meaning and implications of drought in light of a changing world
UNIVERSITY OF CALIFORNIA – SANTA BARBARA
CREDIT: PUBLIC DOMAIN
Maps of the American West have featured ever darker shades of red over the past two decades. The colors illustrate the unprecedented drought blighting the region. In some areas, conditions have blown past severe and extreme drought into exceptional drought. But rather than add more superlatives to our descriptions, one group of scientists believes it’s time to reconsider the very definition of drought.
Researchers from half a dozen universities investigated what the future might hold in terms of rainfall and soil moisture, two measurements of drought. The team, led by UC Santa Barbara’s Samantha Stevenson, found that many regions of the world will enter permanent dry or wet conditions in the coming decades, under modern definitions. The findings, published in the Proceedings of the National Academy of Sciences, reveal the importance of rethinking how we classify these events as well as how we respond to them.
“Essentially, we need to stop thinking about returning to normal as a thing that is possible,” said Stevenson, an assistant professor in the Bren School of Environmental Science & Management. This idea affects both how we define drought and pluvial (abnormally wet) events and how we adapt to a changing environment.
A drought is when conditions are drier than expected. But this concept becomes vague when the baseline itself is in flux. Stevenson suggests that, for some applications, it’s more productive to frame drought relative to this changing background state, rather than a region’s historical range of water availability.
To predict future precipitation and soil moisture levels, Stevenson and her colleagues turned to a new collection of climate models from different research institutions. Researchers had run each model many times with slightly different initial conditions, in what scientists call an “ensemble.” Since the climate is an inherently chaotic system, researchers use ensembles to account for some of this unpredictability.
The results show a world where certain regions are in permanent drought while others experience perennial pluvial for the rest of the 21st century. The team calculated the year in which average soil moisture will exceed the threshold that defines either a megadrought or a megapluvial. “In other words, at what point do average conditions exceed what we would consider a megadrought if it happened now, [and never return to ‘normal’]” Stevenson said.
The western United States has already crossed this benchmark, and there are other places headed that way as well, including Australia, southern Africa and western Europe. “But, again, that’s if we use today’s definition of a drought,” Stevenson said.
The authors argue that we need to move away from fixed definitions toward a more nuanced account of drought and pluvial. “Our idea of normal is, in a sense, meaningless when ‘normal’ is continuously changing,” Stevenson added.
Climate models indicate that average soil moisture in many regions will continue to drop. That said, the team’s ensembles suggests that soil moisture will continue to experience drought-related variation similar to today, relative to the ever-drier baseline.
The fluctuation highlights the need to consider both long term changes and the usual ups and downs associated with historic droughts and pluvials. “The most important management challenge will be to adjust for the relentless declines in water availability, as this exceeds the expected impact of future megadroughts,” said co-author Julia Cole, a professor at the University of Michigan.
Precipitation patterns, on the other hand, will become much more extreme. Warm air holds more moisture than cold air. So as the atmosphere heats up, it’ll be able to suck more moisture from dry areas and dump more precipitation on wet regions.
“We wanted to consider both precipitation and soil moisture at the same time because that can be important for water management,” Stevenson said. For instance, we will need to adapt infrastructure to more arid conditions in the American West, but that infrastructure will also need to handle more intense rainfall.
“When we talk about being in a drought, the presumption is that eventually the drought will end, and conditions will return to normal,” Stevenson said. “But if we’re never returning to normal, then we need to adapt all of the ways that we manage water with the expectation that normal will continually be drier and drier every year.”
JOURNAL
Proceedings of the National Academy of Sciences
ARTICLE TITLE
Twenty-first century hydroclimate: A continually changing baseline, with more frequent extremes
ARTICLE PUBLICATION DATE
14-Mar-2022
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“To predict future precipitation and soil moisture levels, Stevenson and her colleagues turned to a new collection of climate models from different research institutions.”
Ha ha ha ha ha.
In other words, the study is nonsensical.
Regards,
Bob
Nonsensical indeed. What do you do with a collection of models? Please don’t tell me you can average them.
Maybe you can stare at them in wonder?
There lots of things you might do with models.
1)Average Them.
2) Use a Q-test or Students-t test to eliminate the outliers.
3) Calculate the Std. Dev. and RSD, then the 95% confidence intervals.
4) Calculate wee p values.
5) Finally, talk to the astrophysics people and see if they have discovered any exoplanets which might have an environment which matches your models.
FUN!
Be creative, get funding.
There is no definition of “drought” given in this article. Is there a current definition of “drought”? The Drought monitor has totally made it up. Their definition includes satellite visibility of “green”. There is no defined timeframe or % below some median or mean precipitation must fall. Then this article references both “dry” AND “wet” in its consideration of the “new” drought! WTF!? Are they implying that the same amount of moisture is being redistributed via changing ocean currents or something?
Since we have no universal definition of drought … how about conceding THAT first? Before we suppose to change it?
Back in the early 70s I was shown some of the analysis of the then rvently drilled cores of some Great Barrier Reef coral. The bit that interested me most was the finding that for 27 years in the mid 1700s Queensland 2 largest Pacific coastal rivers had deposited no silt on the reef. This was exceptional, as in almost all years some silt from run off from the Fitzroy & Burdekin rivers is deposited by these rivers.
Just imangine the “Global Warming” screams that would go up if Queensland had such a drought today, & if it happened almost 300 years ago, it is going to happen sometime again in the future.
The little bit od knowledge we have today is a really dangerous thing, when considered with how much we have yet to learn.
Reminds me of the barometer question:
How do you find the height of a building using a barometer?
Enjoyed this comment! As an engineering student (all disciplines had to participate), we had to survey a map, including contours, of the campus with roads sidewalks, building outlines and elevations using various instuments, optical, planetable, compas and tape, and yes, barometer! Surprisingly, on a fine midday on the prairies, barometer heights of buildings were reasonably clustered.
The correct answer is ” give it to the Super and ask him how tall it is”
Is there a term for a collection of models, like there is for a collection of crows?
Bogus.
I like that. A “bogus” of models.
“To determine level of future warming, we consulted a bogus of models and smoothed our data to normalize the expenses we claimed against our grant.”
I think a “bogosity” of models has more gravitas.
My heart is bleeding not for the California droughtists as another nice rainfall went through here (the Bay Area) last night and this morning.
Yeah! We got a whole 5/100ths of an inch!!
A “kit.”
An obfuscate.
I like the term ‘crap ton’ as stand in for a collection of climate models. It is both descriptive of their usefulness and indicative of their number.
Is that a standard crapton, or a metric crapton?
Scientific Murder
a funding
A divination.
A charm of hummingbirds.
A murder of crows.
A cabal of warmists.
A bulshyyte of climate models.
A charm of hummingbirds.
A murder of crows.
A cabal of warmists.
A bulshyyte of climate models.
More collective nouns:
Formerly: A gaggle of politicians.
Because all they did was sh!t and squawk.
Now: A murder of politicians.
Because they pushed the deadly Covid-19 “vaccines”.
Still unchanged: A charm of hummingbirds.
A steaming pile of models?
A mo’del of models
A man with one watch knows what time it is. A man with two watches – can’t be sure.
(OK, so you have to be mature enough to remember spring driven watches.)
Models indeed. But I’m reminded of this interesting paper that tried to work with the available ensembles, weighting individual models by their skill, and found most extreme predictions vanished. Perhaps a stop gap way for local governments to inform decisions about future infrastructure needs that acknowledges uncertainty and risk while still appearing to follow the alarmist models.
Observational Constraints Reduce Likelihood of Extreme Changes in Multidecadal Land Water Availability
Abstract:
Future changes in multidecadal mean water availability, represented as the difference between precipitation and evapotranspiration, remain highly uncertain in ensemble simulations of climate models. Here we identify a physically meaningful relationship between present-day mean precipitation and projected changes in water availability. This suggests that the uncertainty can be reduced by conditioning the ensemble on observed precipitation, which is achieved through a novel probabilistic approach that uses Approximate Bayesian Computation. Comparing the constrained with the full ensemble shows that projected extreme changes in water availability, denoted by the 5th and 95th percentile of the full ensemble, are less likely over 73% and 63% of land, respectively. There is also an overall shift toward wetter conditions over Europe, Southern Africa, and Western North America, whereas the opposite occurs over the Amazon. Finally, the constrained projections support adaptation to shifts in regional water availability as imposed by different global warming levels.
I see I am being downvoted, fair enough, but I’m struggling to understand the objection. Essentially I’m suggesting using the alarmist’s models against the alarmist narrative by demonstrating that even if we accept the high sensitivity models that we do not automatically arrive at a “worse than we thought” conclusion. Any insight on the objections appreciated.
Unfortunately, it seems that the votes are usually a reflection of whether or not the reader likes what you have written. Many of the readers have a problem with reading comprehension, and you can always expect at least a couple of the alarmist trolls to vote down anything that goes against the alarmist meme. I’d suggest not paying much attention to the votes.
How did they assess the skill of the models?
If I understand it correctly they compared how well the model matched actual precipitation over the period of overlap between model projection and observations.
This is an alternative to the more common naive ensemble that treats each member as equally likely.
“a new collection of climate models”
Thanks, Bob. You saved me the time reading another piece of worthless climate drivel.
I propose we coin a new acronym.
YAPOG = Yet Another Piece Of Garbage.
As in “This study is YAPOG.”
It has such a nice derogatory sound to it.
YAPOG It has such a nice derogatory sound to it.
________________________________________
Ha ha ha – good one!
I’m trying to get Colorado University’s Sea Level Research Group to be known as C-SLRG and pronounced See Slurg. So far it hasn’t caught on. I wish you better luck with YAPOG (-:
Since that was off topic, here’s some more:
NASA’s GISTEMP just released the monthly update to their Land Ocean Temperature Index (LOTI) for February 2022 and made 243 changes that follow the usual pattern of bumping up values since 1977 lowering most of the values prior to that year. This goes on month after month, year after year in a steady drone. So far since 2003 the gang over Tom’s Restaurant in Manhattan have made over 53,000 such changes.
Happy Ides of March !
“for February 2022 and made 243 changes that follow the usual pattern”
Thanks for the update, I have been wondering about that. GISSTEMP seems to meet the US govt. definition of felony fraud. Specifically using federal monies on research and fabricating data. 53,000 changes over the years, Lordy.
C-SLRG is very good, too. We should use it here.
We missed pie day.
pie is wrong anyway.
Just wait for Tau day.
I like when pie are squared.
Or is that a circular argument?
Pie are not squared; Pie are round. Cornbread are squared.
Unless it’s baked in a muffin tin.
Or in a cast iron skillet. (Best crust)
I didn’t. It was my birthday!
SeaSlug – C SLG – CuSLrG
Your tax dollars at work, Bob. It is fascinating to watch “scientists” take a model that couldn’t predict a bowl movement, run it a bunch of times and treat the average as a modern day oracle. You would have thought they could notice the models don’t match reality.
The lead author is an assistant professor that does her field work in the tropical Pacific. What a gig.
Yes, but it’s studiously nonsensical…
If “The Science is Settled”, why do they need new models?
The old models are getting a bit long in the tooth?
Climate models: the high tech version of “a little bird told me…”
“Essentially, we need to stop thinking about returning to normal as a thing that is possible,”
Define normal.
Before they can define normal, they need to establish that they are the authorities – the ONLY authorities – on what normal is. Then they need to prove that their definition of normal does, in fact, represent the norm.
But they know that they are authorities, they have told themselves that they are so it must be true.
May I be excused?
… and define “possible” (or “impossible”, if it is easier).
People have a normal temperature. Places don’t. Places have at best an average temperature. The US southwest drought drove the Anasazi and other Pueblo tribes out thousands of years ago. It can happen again, and probably will.
And the government doesn’t plan for it.
Define “the”
It is hard to believe there are so many low IQ scientists around.
Well, at least in Climate Science that’d be correct. I’m thinking the brightest see that you can’t question the narrative and if you can’t question something, it’s not science. The good ones see this early on and escape into physics or some other hard research field, although those are diminishing with woke incursions.
Theory: There is insufficient establshed knowledge on which climate science is based. Therefore, there is nothing but guesswork and hunch to separate the wheat from the chaff.
It’s another level
Those than can – do
Those that can’t – teach
Those that can’t teach – become climate scientists
In climate science, all it takes to become a scientist, is for those who are already being called scientists, to acknowledge that you to are one.
Conversely, if those who are currently acknowledged as climate scientists, declare that you aren’t a scientist, you aren’t, and can never be one.
“Climate science” is a branch of the humanities.
It says a lot about the quality of education, and the role of diversity quotas on that quality. When one is more concerned about external, irrelevant characteristics of a person, rather than their ability to think, much mischief is done.
Which kind of drought ? The same kind as the (actually floody) drought that’s been prophesied since years in Australia by the usual bunch of climate clowns ?
Yes, Australia has a floody drought: most of the year there’s no rain, then a year’s supply falls in days and causes floods.
and yet Watts readers continue to pretend that is ‘normal’
Most years ? No rain ? Are you that ignorant ?
“I love a sunburnt country,
A land of sweeping plains,
Of ragged mountain ranges,
Of droughts and flooding rains.
I love her far horizons,
I love her jewel-sea,
Her beauty and her terror
The wide brown land for me!”
-Dorothea Mackellar, My Country 1908.
You are bloody idiot Griff.
Yep, Australia always was and always will be a land of Drought, Flood and Fire.
For Australia, that is normal, and always has been.
“Australia has a floody drought: most of the year there’s no rain, then a year’s supply falls in days and causes floods”
That is mildly true in some areas but not overall. I actually live in Australia and the weather we see is not only relatively regular and predictable it has not really changed much in over a century, as you can see from the poem written in 1908 by Dorothea Mackellar.
It is pretty much “normal” everywhere except in griffland
Yet despite all your dribble the majority of Australians still don’t embrace your belief and they live there 🙂
The unprecedented drought. The drought that had no peer since the authors started attending the kindergarten. They still do.
(University, an institution of higher learning, formerly referred to as kindergarten).
“Essentially, we need to stop thinking about returning to normal as a thing that is possible” – exactly what Klaus Schwab and the WEF want us to think.
The usual load of climate “claptrap” – oh how boring it all becomes – except, of course, for those receiving the golden “shilling”.
I suspect that the east coast of Australia might need a bit of that drought these nuff nuffs are claiming has occurred. Yes, I know it’s just the PDO doing its thing, but using Oz as the poster boy for more droughts (or floods) is a bit daft given the climate history of the last 150 years.
“a new collection of climate models”
Not one, not two, but a collection.
Take an average and then add the number you first thought of
Model outputs reflect the prior speculations of the modeler. In 40 years CliSciFi has been unwilling to change the incorrect assumptions programmed into them. Among many other failings, the lack of a Tropical Tropospheric Hot Spot has been ignored for decades. Science?
Given enough models with random variation, one should be able use an average to erase any appearance of a trend other than the one built into the assumptions that aren’t amenable to calculation — like the energy exchange in clouds.
These “Researchers” do not identify normal variance, ie, drought versus flood cycles without human presence, before they begin “Modeling” a new normal. As a geologist I am aware of the tremendous variance in world-wide climate cycles, and cannot identify any current deviation from that background. Then, after their data torturing (modeling) they predict the Goldilocks scenario: somewhere it will be too dry, somewhere it will be too wet, and somewhere it will be just right.
I remember reading that the Antarctic ice cores showed that Australia has had 40 year long droughts in the past.
The California area has seen 200 year long droughts according to the records. Wonder if they included that in the models?
Time began in, er, 1950
According to griff, it began in 1979.
Science by cartography. Never let it be said that we might confuse the map with the territory.
Sorry Sam, climate is not chaotic – weather might be classed as chaotic.
But even then, weather only appears chaotic in places where it varies a lot and is thus ‘newsworthy’
I’m sure we’re eagerly awaiting your daily news reports of the future telling us that (use Sahara as example)
Mon: Hot dry sunny
Tues: Hot dry sunny
Weds: Hot dry sunny
Thurs:Hot dry sunny
Last week:Hot dry sunny
Last month: Hot dry sunny
You’re gonna sell a lot of advertising with news like that
Also, you talk authoritatively of ‘Soil Moisture‘
Despite your concerns about ‘chaos‘ and ‘change‘ – is it beyond the bounds of all possibility that The Soil might change? Or be changing. Or have changed over the last 100 years.
Are there any good reasons why that might or might not be the case?
e.g. Were ‘The Bison’ of the Great Plains avid and skilled users of 300HP tractors, Mr John Deere’s ‘all steel plough’ and Ammonium Nitrate?
If not, how did they manage to survive for many thousands of years and at the same time produce some the most fertile soil ever seen?
I don’t see your concern about that anywhere in your writings
There’s a scary possibility – what if ‘changing soils’ were:
We know what’s changing the soil. We see it on our breakfast, lunch & dinner-plates while it makes our coffee ‘creamy’ every single day of the year
But you knew that……….
Will someone now please inform The Computer?
PETA,
You might be relying too much on your local knowledge.
Many times, I have flown for an hour or two at Mach 0.7 or so, over lands that have not ever felt the John Deere or maybe even the digging stick.
There is much that has been learned by comparing cultivated soils with untouched soils. Mostly, it is good learning, devoid of alarm and cries of existential threats. Sometimes, the anguished cry is in proportion to limited learning or experience or both. Geoff S
Peta has been schooled on this before. Most land that’s included in Agricultural lands is actually range land that is minimally disturbed from its natural state. The actual percentage of land that gets plowed is small.
Jim Steele’s video yesterday shows actual data proving very little to no changes in rainfall over the lands used in intensive agriculture. In the Eastern US, one of the areas that has experienced the greatest increase in intense agriculture, temps have actually been declining for decades.
Peta’s theory that agriculture is causing deserts which causes climate change is laughably all wet. Despite all data showing otherwise, he continues to push his (debunked) theory.
I wonder why griff never cites Steele’s work in his pronouncements? [rhetorical question]
I thought that there would be more rain. My understanding was that e-e-e-e-vil ‘cahbon’ would heat the oceans and increase water vapor, the major greenhouse gas that would provide a positive feedback loop.
The oceans would boil away and sea levels would increase due to the melting poles.. (I still haven’t figured that one out. Wouldn’t that all cancel out?)
Meanwhile, all the farmland would become cracked and dried while all the trees would leave.
Anyhow, that was my understanding of CAGW. Has been called off?
–
–
–
These alarmist ‘Climate Scientists’ all need to open their hymn books to the same page so they can all sing the same song.
Gorebull warming has been called off for the last 7 years. So far.
Gorebull warming was also called off for over 18 years prior the the latest double Super El Nino. CliSciFi’s response: First alarm and denial, then implausible reasoning, now silence and suppression (with a little historical data manipulation thrown in).
Define ‘normal’ in a chaotic system. Morons.
“Maps of the American West have featured ever darker shades of red over the past two decades.”
Maybe the printer ran out of pantone 186, and is using 187 instead?
We were alarmed when finger paintings by our kindy child were all in black paint. Deep doomy psychology thoughts. Then, the teacher explained that they had run out of other colours. Geoff S
… then the teacher explained that black is the best color, and your child was just trying to placate the teacher, for fear of being chastised & ridiculed.
Returning to normal? We are at normal!
The annoying arrogance of people claiming to know better than nature what normal is. Just ignore them.
Why be normal?
Define drought
Define flood
State how increase CO2 will increase flood or drought in each region, then show data to prove it.
In Richard Feynman 1966 Messenger Lectures, he discusses how to find new laws and the basics of scientifically proving ( or not) a theory.
HE gives the example
“For example, A hates his mother. The reason is, of course, because she didn’t caress him or love him enough when he was a child. Actually, if you investigate, you find out that as a matter of fact, she did love him very much, and everything was all right. Well, then it’s because she was overindulgent when he was young. So by having a vague theory, it’s possible to get either result. Now wait, now the cure for this one is the following: it would be possible to say, if it were possible to state ahead of time, how much love is not enough, and how much love is overindulgent exactly, then there would be a perfectly legitimate theory against which you can make tests. It is usually said, when this is pointed out, how much love is, and so on, “Oh, you’re dealing with psychological matters, where things can’t be defined so precisely!” Yes, but then you can’t claim to know anything about it.”
Feynman was having a go at social scientists in 1966. They haven’t gotten any better.
vaguely claiming somewhere will have more floods and more droughts sometime in the future is social science at its worst.
Models are the current equivalent of examining the entrails of a sheep.
Not even close.
Just imagine what would happen to the Seer if he/she got caught rearranging the entrails before providing the official reading/interpretation.
(That’s what should happen to mann et al)
Models are a little better than that. The problem is how the modelers use the results and how the MSM communicates the results to the public.
When one applies what these academics are saying to say Southern Africa, despite some areas that are very dry, many areas do not seem to have received the alarmist memo. A number of the dry areas have received good rain and overall most dams are pretty full.
Simple question this morning… Since every “ensemble” plot of climate models for temperature I’ve seen demonstrates no particular skill at forecasting temp, why should we pay any attention to an ensemble prediction of drought?
Logically, every ensemble has at least one (allowing for a tie) best prediction. The problem for the modelers is how to identify that one best prediction, and demonstrate that it isn’t just luck. That is, that it can be reproduced from the same model. If it isn’t reproducible, then there is a problem of reliability. That is, none of the individual runs have skill in predicting, and the ensemble average dilutes the theoretically best result with all the poor results.
P.S.: If the ensembles have large inter-model variations, and the only way to test them is to compare them to [altered] history, there is really no reason to believe that they aren’t just ‘curve-fitting’ or lucky outcomes, and actually have no more predictive value than fitting a high-order polynomial to the historical data.
Or, maybe we poorly timed our development of water management in the West. The drought will end in roughly 10 years.
https://www.pnas.org/doi/10.1073/pnas.0306738101
That is bourgeois science. At least according to Mickey Mann who claims that the AMO doesn’t exist because it doesn’t figure in his model. A bit like Lysenko who claimed genes do not exist.
When “climate scientists” use models, they never seem to select the 4 or 5 that come closest to matching observations and then averaging them to produce their projections. Or maybe I have missed something. Why is that?
It has been explained by people knowledgeable in the field that the decision to use all of them was political; there are multiple nations with teams running the models. In the UN IPCC CliSciFi AR6, however, they had to throw out a bunch of the models that were running egregiously hot. The CMIP6 hot models, along with RCP8.5-type scenarios, are still being used for “scientific” studies.
Anybody that believes the UN IPCC and U.S. National Assessment reports are anything more than political propaganda is a fool. They both lie in saying that severe weather-related events are becoming more frequent. Dr. Roger Pielke, Jr. is highly critical of both.
It’s well known that the current “ensemble” of climate models have predicted higher temperatures than those that are currently measured. Now, when you add to them a drought factor that “as the atmosphere heats up, it’ll be able to suck more moisture from dry areas and dump more precipitation on wet regions”, viola!…You’ll predict droughts.
That ain’t science. It ain’t even witchcraft. It’s simply propaganda.
I remember driving around California in the mid 70s and coming to a bridge hundreds of feet above the river below. There was a sign on the bridge: “No diving off Bridge”. Even a fool would never jump to certain death there. The sign, though, was meant for non drought conditions, where the reservoir below was filled with water. Some indeed had safely jumped off the bridge into the reservoir. A couple of years later, the reservoir was refilled and the sign was appropriate. Droughts come and go. It’s called “weather”. Sometimes they even go for a long time before they come back. That’s called “climate”. The so-called “Climate Models” obviously don’t have enough fidelity to accurately predict when the weather diverges from the climate.
“A drought is when conditions are drier than expected”
My Vodka Martini was drier than expected. Given its ‘extreme’ I’m going to call it a Vodka Drought.
Ah, but you had it shaken, not stirred!