Not only does the wet get wetter over land, but the driest areas get wetter too
From the UNIVERSITY OF NEW SOUTH WALES and the “Flannery says permanent drought over Australia” department
Global warming will increase rainfall in some of the world’s driest areas over land, with not only the wet getting wetter but the dry getting wetter as well.
New research published today in Nature Climate Change has revealed that in the Earth’s dry regions, global warming will bring an overall increase in rainfall and in extreme precipitation events that could lead to flash flooding becoming a more regular event.
“We found a strong relationship between global warming and an increase in rainfall, particularly in areas outside of the tropics,” said lead author Dr Markus Donat from the ARC Centre of Excellence for Climate System Science.
“Within the tropics we saw an increase in rainfall responding to global warming but the actual rate of this increase was less clear.”
Unfortunately for societies, businesses and agricultural activities that exist in arid regions, the expected increase in rainfall over dry areas does not necessarily mean that more water will become available according to the researchers. The additional heat caused by global warming will likely lead to increased evaporation. This means that while there may be more extreme flooding events it may have little impact on overall water storage rates.
“The concern with an increased frequency and in particular intensity of extreme precipitation events in areas that are normally dry is that there may not be infrastructure in place to cope with extreme flooding events,” said Dr Donat.
“Importantly, this research suggests we will see these extreme rainfall events increase at regional levels in dry areas, not just as an average across the globe.”
The researchers were able to reach this conclusion because they looked at regions with similar characteristics rather than trying to compare complex climate variations found when comparing one country or continent with another.
This meant that dry regions in Australia were compared with similarly dry regions in Asia, Africa and many other countries. At the same time, wetter regions across different countries were also compared. This allowed the researchers to directly compare like with like.
Importantly, the findings remained consistent across observations and models.
“With precipitation climate models and observations don’t always tell the same story regarding regional changes, but we were very surprised to find that our results turned out to be highly robust across both,” said Dr Donat.
“It appears the uncertainties in climate models were greatest where the observational uncertainties were greatest. This suggests that improved observations will be vital for those planning for climate change if they are to reasonably determine how future precipitation will change in every corner of the world with global warming.”
###
The paper:
More extreme precipitation in the world’s dry and wet regions
Markus G. Donat, Andrew L. Lowry, Lisa V. Alexander, Paul A. O’Gorman & Nicola Maher
AffiliationsContributionsCorresponding author
Nature Climate Change (2016) doi:10.1038/nclimate2941
Received 23 July 2015 Accepted 20 January 2016 Published online 07 March 2016
Intensification of the hydrological cycle is expected to accompany a warming climate1, 2. It has been suggested that changes in the spatial distribution of precipitation will amplify differences between dry and wet regions3, 4, but this has been disputed for changes over land5, 6, 7, 8. Furthermore, precipitation changes may differ not only between regions but also between different aspects of precipitation, such as totals and extremes. Here we investigate changes in these two aspects in the world’s dry and wet regions using observations and global climate models. Despite uncertainties in total precipitation changes, extreme daily precipitation averaged over both dry and wet regimes shows robust increases in both observations and climate models over the past six decades. Climate projections for the rest of the century show continued intensification of daily precipitation extremes. Increases in total and extreme precipitation in dry regions are linearly related to the model-specific global temperature change, so that the spread in projected global warming partly explains the spread in precipitation intensification in these regions by the late twenty-first century. This intensification has implications for the risk of flooding as the climate warms, particularly for the world’s dry regions.
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Fewer, or smaller, deserts sounds awful. As for flooding, that’s what arroyos are for. And the question of models vs. observational facts rages on, and on, and on.
Did you not read the press release? It states, “Unfortunately for societies, businesses and agricultural activities that exist in arid regions, the expected increase in rainfall over dry areas does not necessarily mean that more water will become available according to the researchers. The additional heat caused by global warming will likely lead to increased evaporation. This means that while there may be more extreme flooding events it may have little impact on overall water storage rates.”
That is not consistent with your statement “Fewer, or smaller, deserts sounds awful.”
That’s right up there with global warming causes more snow, I understand the Sahara has greened about 500 km further north. That must be unfortunate for the poor sand dunes. Children just aren’t going to know what deserts are!
It is probable that precipitation has increased in dry areas, as there has been a global greening, much of it in arid areas.
Floods however, on global scale, shows no trends, according to the IPCC.
And of course local populations will do nothing to control or capture this increased rainfall because they don’t have advanced degrees in “climate science” and are therefor too stupid to act in their obvious best interest, according to the researchers.
I don’t quite know how to break this to you; well to the author of that press release you just cited; but it is exactly that (any ) global warming that causes increased evaporation, that is a prerequisite for increased rainfall.
Why do people continue to ignore the Wentz et al paper, that shows (experimentally) that global evaporation (rate) and global precipitation (rate) must be equal, and the integral of both which is total atmospheric water content also increases (experimentally observed) by the same amount as the rate increase.
They found that for a one deg. C increase in global surface Temperature, those three numbers increase by 7%.
I believe that the Clausius-Clapeyron equation for the global conditions, also predicts exactly that 7% per degree response.
I’m not an expert on the C-C equation (Prof Will Happer is), but I believe it is quite well established Physics.
The GCMs do not calculate the same result for all three numbers, that Wentz et al observed experimentally, but I believe they do agree on the one that derives from C-C.
G
I should add, that although I believe global warming increases global rainfall (precipitation), I’m not prepared to endorse ANY claims as to where such increased precipitation occurs.
We all know generally how the monsoon phenomenon goes, and that water clearly evaporates from the tropical oceans, but comes down as some sort of precipitation somewhere else.
I have no basis for believing that such increased precipitation might choose to bless some previously arid region.
But I’d be quite happy if that happened.
Globally, we will get more precipitation, if global warming happens.
G
In deserts, water usually soaks in, not evaporates.
In Albuquerque they have ponds where rain water is stored so that it has time to percolate down to the aquifer.
george e. smith comments are all you need to understand warming’s effect on precipitation. What goes up… must come down. Most falls on the oceans – the rest on to land – some will fall on arid land, where the benefits are maximized. It cannot be any other way. GK
Sounds like bad news for Ant Lions
deserts by definition
“DESERT
noun | des·ert | \ˈde-zərt\
Definition of desert
1 a: an arid land with usually sparse vegetation; especially : such land having a very warm (or cold) climate and receiving less than 25 centimeters (10 inches) of sporadic rainfall annually
b : an area of water apparently devoid of life”
are areas of little annual precipitation. If the annual precipitation rises above that threshold then that area is no longer a desert and begins to morph into grasslands or treed grasslands. Satellite images indicate such a greening is already happening in the extreme southern Sahara
So
That desert IS getting smaller and “fewer, or SMALLER, deserts sounds awful” is accurate and not necessarily inconsistent with the release.
This sounds frightening. If true, increased evaporation must go somewhere, no?
You forgot to factor in, the increase of CO2.
As always, the global warming troughers are always glass half-empty. As if people don’t know how to build cisterns. Also, more rainfall in drier areas would mean a change in the vegetation that can grow there. That might allow trees to grow where only grass currently does. And forestation would mean better water retention in the soil.
Thanks for the laughs.
Dude, I love the word may in places like this. Instead of doing a prediction, a statement is done that is ‘not inconsistent with’ any possible outcome. Look, I have an out-of-jail card! I said ‘may’.
That said, increased rain at desert of course increases evaporation – how could it not – which reduces temperature swings and makes the desert less desert-like.
So where’s that giant C for catastrophic?
Sounds like Dr. Donut’s hypothesis may have a few holes in it
Okay, how are all these “on the other hand, its not all bad” articles getting published all of a sudden? These seem to represent a significant backing away from the all-catastrophism all-the-time we’ve had for over a decade. Is the gig really up?
And if it is, where’s my schadenfreude? 🙂 Are we going to let these journals off the hook that easy? We know and they know that in the eye of the public, the next La Nina will knock this CAGW nonsense out for good. Are they trying to go away quietly here?
Publication was only accepted because of this:
“
Are they observing more rain in dry areas,or is it the models predicting more rain in formerly dry areas? A rather major difference, especially if it is not both.
They are supposed to only predict doom. What went wrong with the models?:-)
Don’t worry about it, a new model will come along next week.
“It appears the uncertainties in climate models were greatest where the observational uncertainties were greatest. ”
It’s all the fault of the data.
For the sake of argument lets say in the unlikely event that temperature goes up 2C in a 50 years, how is that enough to evaporate away all of the water that is plentiful enough to cause “extreme” flooding. And does the evaporated moisture go into a GW black hole, or does it just come back down as you know rain or excuse me “extreme” precipitation to eventually collect in ravines/gullies and depressions becoming rivers and lakes.
They are trying way too hard to explain away good news.
Hello CO2 induced global cooling. It’s worse than we thought, we had it right the first time in the 70’s. Back to drought predictions with this paper in the references.
Don’t expect to see this headline anytime soon on CNN:
Has anyone mentioned that large areas of the Sahara were habitable, away from the Nile, around 4000-6000 years ago, when temperatures were at their peak? It was cooling that made Egypt drier, and forced relatively free people to crowd the Nile and adopt a system that led to pharaohs and pyramids.
I imagine it would be a good thing if the situation was reversed, and millions of acres of uninhabitable land became habitable. “And the deserts will bloom.”
Horrible, I say, horrible!
risk of flooding as the climate warms, particularly for the world’s dry regions.
===========================
if there is more rain of course there is an increased risk of flooding. if there is no rain there cannot be flooding, so the risk would be zero. any rain will therefore increase this risk to something greater than zero.
this really points to the misleading use of language. ask the people that live in the desert regions if rain is a good thing. you will find they pray for rain.
now ask the people that live in desert regions if they are worried about flooding if it rains. would they rather there was no rain and thus no risk of flooding. they will look at you like you are crazy.
It was always really easy – if there are clouds on the mountains, get out of the Arroyos and dry gulches that lead toward those mountains. Flash flooding was just a way of life that was easily dealt with if one paid attention.
Actually, I live on the desert in Yuma, Arizona, because of the dry heat and sparse rainfall. We call arroyos washes. The drainage on both sides of the Colorado River is aimed straight at the nearest river and in heavy rain you had best not be in the way of the water. Yuma wash is a raging river as it collects water from smaller washes and often takes out U.S. 95 for a time before heading toward the Colorado.
That said, there have been an increase in small showers in general over the last couple of decades and it is no longer unusual to see large flat areas and small hills covered in grass during even August. Gourds , which were common along roadways until a few decades back, are starting to reappear at higher elevations (three to five thousand feet) elsewhere in Arizona.
Ernest, I live in Phoenix (originally from Wisconsin). Do you mean ‘gourds’ the vegetable, a wild variety?
Izzit true that place was named after the first (now deceased) chap who rode into town on the day of the choosing of a name ??
g
@az1970 – yes. One of the first things I remember on visiting in the 70’s was gourds growing along roadsides as we rode around the state.
@george – Yuma was originally called Arizona City. Don’t know when it became Yuma or why.
Spot on. You nailed ’em.
Because so much water is being drawn from it, the Colorado dries up long before it reaches the Gulf.
If there was so much extra water, it would end up in the Colorado and it would provide more water for drinking and agriculture for all the communities downstream.
Some Colorado River water reaches the Sea of Cortez most non drought years, as per treaty with Mexico.
What was diverted helps to water and feed tens of millions of ex-Mexicans living in the US.
It would mostly wind up in Mexico helping farmers there. What remains at Yuma is drawn off by Mexico at Morales Dam. The river channel below the dam is bone dry except when it rains south of the dam. If we were to see the water levels of 1981-82, when water off the entire drainage system starting with the Snake and Green rivers were at flood levels, every dam including the Morales dam would be wide open trying to save threatened dams and flooding. At Yuma the water was up on the levees that protect many low lying areas. It was a little scary.
Ferd
As in “Welcome Rain”
https://weberstudies.weber.edu/archive/archive%20D%20Vol.%2021.2-25.2/Vol.%2021.3/Tixier%20Poe.htm
How does “global warming, ” which I assume is warming over the entire Earth, affect regional rainfall? Did they look at regional temperatures and see how that relates to the rainfall over the same area? Seems like that would make sense.
So, they expect more warmth, more rain and additional CO2 fertilisation. That doesn’t sound too bad, really.
And now that we know climate sensitivity is much lower than they told us, I think we can safely say that The AGW Catastrophe is off the menu.
My latest computer model (in my head) says that increased warming will bring about increased precipitation and a longer growing season leading to increased use of co2 by plants and increased food supply for humans. It’s a win win win for everyone. There are no negatives in this model. 🙂
There are no negatives in this model.
==============
no one is going to give grants to researchers to study the positive effects of global warming, because good news doesn’t sell. without grants (government hand outs) how will scientists survive?
horror upon horrors, will the likes of Mickey Mann be forced to get real jobs? If nothing is done the earth will spin out of its orbit as temperatures increase past the tipping point, and the earth falls over. We must pay a tax for the sin of CO2 and prevent this. Otherwise in 100 years we will all be dead.
‘Thank you for your application Mr. Mann. Can you show me the accuracy of previous forecasts?”
Increases in total and extreme precipitation in dry regions are linearly related to the model-specific global temperature change
=================
so they’ve solved the problems with modelling clouds have they? because a linear relationship at the regional level sounds like a significant modelling problem.
what you should see regionally is that some regions get wetter and some get drier, as temperature change leads to seasonal changes in wind speeds and direction. a non-linear relationship at the regional level.
this suggest that the model is not describing reality. or that the change in temperature is so small in absolute terms, that the effects are so small that they approximate a linear relationship.
I don’t know why this is hard. Areas downwind from the oceans will get more rain. Areas in the lee of mountains will see a little more rain as it won’t all get squeezed out before the clouds pass over the mountain, but still not much rain will fall. So unless there is going to be major changes in the circulation patterns of global winds, I think it is safe to say that wet areas may get a bit wetter and dry areas might get a bit of water, but wet areas now will still be wet and dry areas now will still be relatively dry. The only question is will it turn currently marginal water conditions into agriculturally viable ones. Humans have dealt with flooding for millennia, that is a simple engineering adaptation.
Cold and dry kill. Warm and wet are merely engineering problems to adapt to.
Reminds me of my girlfriends, past and present. I need to keep this in my mental vault for future reference.
More rain, means more clouds. Shouldn’t that make the surface temperature cooler?
They’re working really hard to find a cloud in that silver lining.
This is a typical paper from our “climate scientists”.
It might get wetter in dry places but to the point that there might be flooding, but if it does flood, the higher temperatures might evaporate the moisture so that there might not be any net benefit to crops or to lakes.
is this all it takes to get on the gravy train?
Does this paper say anything, or am I just too stupid to understand it?
“Global warming” is, of coUrse a nonsensical term. There is no scientific agreement
As to what it means. The warmers stick to their definition which covers only 30 per cent
Of the globe and is heavily contaminated with urban heating readings which can easily
Be 6 degrees C. Too high while ignoring the validated record of satellite readings which is very
Accurate and covers 80 per cent of the globe.
You can drown in water! … it’s worse than we thought. We’re going to need an international umbrella crisis group meeting. Maybe in the Vatican?
If it rains more, we will need more umbrellas. So having a meeting about umbrellas would be a good idea.
dihydrogen monoxide Global killer – It is critical. We must act now to eradicate this poison.
Perhaps the EPA should call it a pollutant!
I’d rather call the EPA a pollutant.
Doesn’t the latent heat of vaporization sort of dampen warming? I mean, when a drop of alcohol evaporates off of my arm I feel it cooling. Wouldn’t all that new rain over previously arid, hot surfaces cool them as well? Where is that effect captured? Doesn’t that act as a dampening effect on this “catastrophic” warming that’s always just around the corner? Not to mention the vertical mixing that the less dense air causes, bringing cooler high altitude air down to the surface?
The effect of moisture is complex. As I show today, rising humidity which results in lower cloud levels would lead to significant global cooling. However if you had increased water uptake which was matched by increased precipitation, there would be no effect on global temperature:
Can variations in lapse rate & cloud cover explain ice-age temperature changes and the inter-glacial “hard stop”?
This may be a foolish question, but why does the TOA radiation have to balance the incoming?
– Are we saying none of the energy from the Sun is transformed? (i.e. captured by the biosphere?)
It takes energy to evaporate water. If evaporation rates increase, then temperatures will be less than they would have been. Even without changes to the clouds.
MarkW has hit on my point. Basically, when water falls on the desert, and is re-converted to water vapor, it has to absorb energy to make the transition. The change manifests as a lower temperature, just like a swamp cooler functions. You have to account for that energy transfer somewhere.
Well I assume that JonA is saying the TOA gosinta equals the TOA gosouta, and asking why.
Well yes there can be some “missing heat” immediately if you figure what is turned into wood etc. or starfish.
But I believe the presumption is that eventually those bio materials will recycle; the wood will get tossed on a comfy fire, so it will eventually degenerate to heat (noun).
So the time element complicates the accounting.
G
To the extent that the total mass of wood and starfish is going up, there may be a temporary imbalance in the energy flow.
However once the total mass stabilizes, there will be balance again.
There can also be temporary changes as oceans warm, or ice melts, but over the course of a year, these should come pretty close to balancing out.
Anything that extracts heat (noun) energy from your skin, makes that spot feel colder, because it is colder. Remember that body Temperature is 98.6 deg. F or 37 deg. C, and your body feels decidedly cool or hot, if that Temperature changes by -/+ 5 deg. F, or say 2 deg. C
So doesn’t take much cooling for you to be able to sense it on your skin.
If you mix equal masses of refrigerator Ice at zero deg. C and McDonalds Hot (80 deg. C) coffee water, and stir it a little, all of that ice will melt, and you will have twice the ice mass of water all at ZERO deg. C
Latent heat is good.
G
Using science to explain things. Isn’t that unfair?
You know what’s really cool? (yeah, there’s a pun here somewhere) I can post a view/question on this site, and get thoughtful and reasoned responses. Do you know how rare that is? Unicorns are waaay more prevalent than these conditions. So a general thanks and shout out to the group at large for their intelligence and bonhomie. It is recognized for the rare and valuable thing it is.
Well that would be a neat trick. Drier areas will be wetter but that will still make them drier.
“Unfortunately for societies, businesses and agricultural activities that exist in arid regions, the expected increase in rainfall over dry areas does not necessarily mean that more water will become available according to the researchers. The additional heat caused by global warming will likely lead to increased evaporation. This means that while there may be more extreme flooding events it may have little impact on overall water storage rates.”
“The additional heat caused by global warming will likely lead to increased evaporation.”
Yup and evaporation and transpiration cool things down.
The concern with winning the lottery is that there may not be infrastructure in place to support spending the money.
Warmer is wetter. Colder is drier. That about sums it up.
I propose that when the world finally understands this whole debacle is a farce we don’t tell the ‘climate scientists’ .. instead we should tell them they’re still Very Important and maybe hire a puppet to pretend to be The President, and tell them they’re consultants to said puppet. We could televise their antics and shrill claims on a comedy channel and small children can be warned of the dangers of delusional self importance and not paying attention in science classes.. I can just hear people in the future quoting punch lines in a pythonesque manner as people fall about laughing in response to someone straight faced saying ‘climate change’.
Sadly, a new hysteria will overtake humanity and we’ll all worry about the price of walnuts or catastrophic beagle attacks or something equally idiotic – but at least having a Man in a cage to giggle at might go some way to paying off the debt they’ve incurred
” Sadly, a new hysteria will overtake humanity and we’ll all worry about the price of walnuts or catastrophic beagle attacks or something equally idiotic ”
?quality=75&strip=color&w=814
Time magazine has already cast its vote for the next stupid, hysterical issue.
my calculator is missing..hmm so whats 1.5% is it? (was hard to read the small print)
of what? 310 Million americans
400 k? give or take a few thou
when is a minority like that considered a tipping point?
tip the entire idiocy out seems like an idea.
😉
“Importantly, this research suggests we will see these extreme rainfall events increase at regional levels in dry areas, not just as an average across the globe.”
No, there is nothing important about this research. No one is moving; no projects are being canceled. Outside of academia, it is just noise.
Luke on March 9, 2016 at 7:04 am
Did you not read the press release? It states …expected increase …does not necessarily… will likely … while there may … it may have….
Now, THERE is some HARD science for ya!
That’s with all other things remaining equal. Other things never remain equal.
With more water and more CO2 more plants can grow. That means the water won’t just wash off the land. We have a choice of which plants are grown on the land. That should take care of the evaporation problem.
These guys will bend themselves into pretzels to find the cloud attached to the silver lining. Back when the Earth was warmer, about 9500 BCE, much of the Sahara was lush.
World History should be a required course for climate scientists. It would make them less stupid.
When one is being stupid on purpose, the only thing that will make one less stupid, would be a conscious desire to be less stupid.
That reminds me of my favorite Upton Sinclair quote:
The IPCC’s AR5 Report basically says they stink at predicting precipitation.
Doesn’t it also say that they stink at regional forecasts in general?
Maybe this will be a new trend in climate science studies – you have to read between the lines to see that the study is really saying, “Hey, a warming world is a much better place to live in, but I have to earn a living so please forgive me for receiving the grant money for this study. It takes time to change careers, you know.”
The story goes “Dry places will be drier, and wet places will be wetter” but the world doesn’t necessarily divide up nicely that way.
You would think Arizona is dry and coastal Oregon is wet but, for the summer months, that’s not the case; there are wet and dry seasons.
So, I can see how a wet season can be wetter with more rain falling in the same time-span but the only way a dry season can be drier is for it to extend into the wet season, thereby making the wet season drier.
Of course, a wet season can also be wetter by lengthening into the dry season and the result is a wetter wet season and a wetter dry season, all from the same wetness.