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.
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.
How times change.
2004
Antarctica is likely to be the world’s only habitable continent by the end of this century if global warming remains unchecked, the Government’s chief scientist, Professor Sir David King, said last week.
http://www.independent.co.uk/environment/why-antarctica-will-soon-be-the-only-place-to-live-literally-58574.html
Charlie, Izzat Professor Sir David King, a Brit or a Kiwi.
I tried telling PM John Key to get with Australia, and tell the IPCC to go and pound sand; but he referred me to a Sir somebody something, who was his science advisor, and he was all into the coolade of climate change. (AMMGWCCC).
G
This is important. More heat flux at the surface increases the velocity of the water cycle, an important negative feedback on temperature. Remember.
” …… improved observations will be vital for those planning for climate change ….. ”
Does this mean that someone has had a small common sense implant?
” …… improved data corrections will be vital for those planning for climate change ….. ”
Fixed.
Hmmmm…. Wouldn’t increased evaporation cause a significant decrease in air temp? That whole phase change thing? But I’m just a thermal engineer.
Yep. That’s a negative feedback mechanism, which tends to reduce the effect of climate forcings.
Please!There is no room for reality here! The grant stream might dry up!…..Oh , wait…..wetter is dryer! See, we told you so!
Yes,
the Anasazi (Pueblo) Indians in the American SW would totally agree.
….until the Little Ice Age dried things up and made them deceased.
Who told them they should stay there and put up with that ?? Most of the other Native Americans, all of whom carry the same Uzbeki gene, managed to survive the little ice age, as well as the mediaeval warm period.
g
The Darwinism is strong in this one… 🙂
Yeah, they just became the subjects of a popular book.
g
I think this story really belongs in the “Everything that changes is bad, even when it is good” department.
If there is more evaporation that will both cool the land and provide water vapor for the next round of rainfall.
Extra CO2 also makes plants more drought resistant and water-efficient, by improving stomatal conductance relative to transpiration, which is especially helpful in arid regions. (Google finds many articles about it.) When air passes through plant stomata (pores), two things happen: the plant absorbs CO2, and the plant loses water through transpiration. When CO2 levels are higher, the ratio of CO2 absorbed to water lost improves, which improves both plant growth and drought resistance. The plants also commonly respond to elevated CO2 by reducing the density of the stomata in their leaves, which reduces water loss. As a result, some of the world’s deserts and near-deserts are greening.
What makes me wonder if I’m going nuts, is the energy conservation aspect, or lack of it in these folks’ thinking.
Just how many times do they use the same energy –
1. it warms the place – has that not used it up?
oh no
2. It evaporates a load of water. Now play the game, it takes a SHEDLOAD of Joules, didn’t they just get used doing the warming?
no matter
3. the evaporated water condenses as rain, and surprise surprise, there’s another shedload of energy rides over the hill to evaporate it all again.
Where’s it all coming from?
What I suspect, is that these people base their physics on what they see happening in their shower or bathroom (with a coal fired power station driving it) and is diametrically opposed to what goes on ‘out there’ in The Real World
“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”
With more rainfall especially if long term then you will get things growing and the formation of lakes etc., therefore the land will absorb the rain as it won’t be hard, dry and parched. And have the researchers not heard of the African Humid period when the Sahara was green (between 11,000 to 5,000 years ago)? At that time temperatures were higher than now.
http://www.nature.com/scitable/knowledge/library/green-sahara-african-humid-periods-paced-by-82884405
Anyway, with more evaporation it is likely to feel cooler.
It is well known that elevated CO2 levels increases plant growth and yields. Studies have shown elevated CO2 levels reduce water demand of plants thus enabling them to grow in more arid conditions. An earlier post here (http://wattsupwiththat.com/2016/02/16/study-increased-carbon-dioxide-is-greening-deserts-globally/) reviews a study by that showed deserts are greening and “the greening likely stems from the impact of rising levels of atmospheric carbon dioxide on plant water savings and consequent increases in available soil water”.
This study found that increased temperatures has resulted in increased rainfall.but it appears the authors threw out some wild conclusions on the effects of this increased rainfall.
From where I sit, it seems that this is one more argument for an improving climate regime and the possibility that the arid areas of the world may be able to feed their starving populations. – Something that should be celebrated.
Even if it turns out to be true, it assumes we are not going to get better at stormwater conveyance or storage in the future to adapt. Stormwater is becoming seen more and more as a resource…many developed nations will use it as such within the next 20-25 years.
A neighbor of mine when I was growing up, got a couple of plastic barrels and fed the downspout off of her roof into them.
She used the water she collected for her garden.
My sister would sometimes put out pots and pans when it rained and she used the water to wash her hair. We had very hard water where we lived.
I remember 40 years ago (mid 1970’s) the first time I heard of climate change, there was a lot of publicity about the Sahara desert expanding southwards into the semi-desert Sahel region, and the semi-desert in turn expanding southwards into hitherto fertile regions of tropical Africa. I remember this expansion of arid conditions being discussed and documented, and this was in the years before the ideological battles over natural versus anthropogenic climate change really took off.
If my memories about what was being discussed 40 years ago are correct, surely the continued progress, stabilization, or even reversal of desertification in the Sahel at the present time should provide a test-case for your thesis that global warming might make dry area wetter. As one of your earlier commentators pointed out, parts of the Sahara itself were fertile during the post-glacial warm period.
Is the atmosphere wetter or not. I wanna know. AGW says it must be. That’s what’s causing the warming.
Ben Santor said in 2007 it is.
Well, in 2007, according to model simulations.
https://www.newscientist.com/article/mg19526224-500-wetter-atmosphere-points-to-global-warming/
“””Benjamin Santer, a climate scientist at Lawrence Livermore National Laboratory in California, and his colleagues studied satellite measurements of the water content of the atmosphere. They found that total moisture content over the oceans had increased since satellite records began in 1988, but the question remained whether or not this was due to human activity.
So Santer’s team combed through a database of computer simulations involving 22 different climate models, far more than any previous study. This reduced the risk that the idiosyncrasies of any particular model would influence their conclusions.
Some of the simulations included greenhouse gas emissions, some included natural factors such as volcanic eruptions and fluctuations in solar radiation, and some included both or neither.
When they compared the results of the simulations and matched them to the satellite data, the researchers found that the simulations for increased greenhouse gas emissions gave the closest match (Proceedings of the National Academy of Sciences, DOI: 10.1073/pnas.0702872104). Moreover, the amount of extra moisture in the atmosphere was very close to that predicted …””””
So wetter is a negative feedback.
Further the rain that should fall in those arid areas will fill the falling aquifers thus constraining sea level rise and feed a world even more effectively.
There is a lot to enjoy in this. Every time I have been in the Australian dry regions it is the very clouds that give respite from the sun 38C or 40C is moot but the sun obscured by cloud is bliss.
“The additional heat caused by global warming will likely lead to increased evaporation.”
In reality the warm AMO since the mid 1990’s has caused a number of drier regions to become drier, and hence a source of recent surface warming. The cold AMO and multi-year La Nina in the 1970’s caused land surface cooling because of the increase in precipitation. If CO2 had the power to increase positive North Atlantic Oscillation states enough to drive a cold AMO, then the effected dry areas would become wetter. Though if CO2 did had such power, the AMO would not have warmed from the mid 1990’s.
http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch10s10-3-5-6.html
Global warming will, according to the Guardian, make Saruman escape from the Ents at Isengard, reforge the ring of power and become the new dark lord of Mordor.
Global warming will, according to the Guardian, make fingers breaking through toilet paper a more frequent occurrence.
Global warming will, according to the Guardian, make the likelihood of Windows attempts to automatically solve a PC problem, which is already zero, become even less.
Global warming will, according to the Guardian, make Batman assassinate the joker and become himself the evil ruler of Gotham City.
Global warming will, according to the Guardian, make the ship Titanic refloat from the ocean floor and all her intombed crew and passengers come back to life.
Global warming will, according to the Guardian, make England the winners of the next soccer world cup.
Now you’re just being silly.
30 Years ago I worked in Tennant creek (Australia) and it was dry as all the time ,red Pindan dust was everywhere and got into everything .went through last year and it had changed completely .
Green grass knee high ,water in the creeks ,the vines and trees reminded me more of the far north tropics than the Tanami desert .
But I think we need to look at the past climate to predict future climate and even then it’s all just a guess ,as we know the climate changes between ice age to warming and maybe the only thing man could ever do to stave off an ice age would be to burn every lump of coal in the ground but even then we have no idea no proof no evidence to confirm this either way .
Robert — please see for rainfall variability and soil-water balance simulations my Ph.D. Thesis “An agroclimatic classification of the semi-arid tropics” which is available in The Australian National University, Canberra Library [1985]; and A paper “Soils and Climate” by J. Williams, K.J.Day, R.F.Isbell and S.J.Reddy [1985; pages 31-92] piblished in a book “Agro-Research for the semi-arid tropics: north-west Australia” Edited by Russell C. Muchow, University of Queensland Press, St Lucas, London, New York. They are highly variable — starting and ending periods show very high. Because of this the proposed commercial agriculture over this region failed.
Dr. S. Jeevananda Reddy
Izzit prohibited to use 4-letter words in a PhD thesis title ?
g
What caused all this ruckus…http://earth.nullschool.net/#current/wind/surface/level/overlay=total_precipitable_water/orthographic=134.76,-27.38,1209
Hydrological cycle and temperature versus precipitation are theoretical exercises. They are modified by several localized conditions. One of them is wind speed and direction.
In early 70s an article was published by eminent British Scientist in a reputed Journal wherein he showed precipitation in “Thar Desert” is increasing. As usual I went to the IMD [next to my place of work] library during lunch break, the librarian showed this publication. We found the error wherein he did not accounted change in units from inches to millimeters from 1957. This was brought to the notice of DDGC and he in turn informed the author. The author withdrew the paper from the Journal.
The general theory is in April if Northwest India [Thar Desert zone] warmer, we get the early monsoon [over Kerala Coast] and thus good monsoon rains. The fact is the onset of monsoon varies between 15th May and 15th June with an average date of 31st May/1st June – follows a 52 year cycle similar to Fortaleza Precipitation in northeast Brazil. Also, the monsoon reaches the Northwest India in flag end of the monsoon.
The Indian Southwest Monsoon starts just before the Sun reaches its northern point in the Northern Hemisphere in June and ends by September when the Sun crosses over to Southern Hemisphere. The seasonal temperature variation reaches maximum in May and Minimum in January. Thus, the Northeast Monsoon starts in the descending phase of temperature in October [post-monsoon season]. This is the period when severe cyclonic activity occurs. They follow a 56-year cycle similar to the Northeast Monsoon precipitation — Southwest Monsoon precipitation at all India level presents a 60-year cycle. The Northeast Monsoon Rainfall presents high year to year variability compared to Southwest Monsoon Rainfall. Pre-monsoon season [before June] occurs not only thunderstorms but also occasionally cyclones. El Nino years present a range of rainfall patterns, starting from deficit to normal to excess rainfall over different years.
The other main issue that controls the precipitation pattern over different parts of the country is Climate System like Orography — Western Ghats, Eastern Ghats and Himalayan Ranges.
There is no global warming as such, the word global warming is only a misnomer. This global average temperature [example of one degree rise] is an average of temperatures over different parts/regions of the globe wherein they are controlled by local conditions that are varying with the time over the natural variations.
It is the right time that researchers/research institutes must give top priority to look into more of local and regional investigations that help people of the region rather than time pass global hypothetical studies. It has no use and at the same time waste public money.
Dr. S. Jeevananda Reddy
Global warming means that the Antarctic highlands (Vostok Station) now only gets down to -93.4 deg. C instead of all the way to -94 deg. C, like it was 150 years ago.
g
AP stylebook might allow that to be described in public with pretenses of credibilty as “baking.”
I don’t know about what effects “warming” is having / will have on rainfall but CSIRO was quite clear that its research showed rising CO2 [CO2 fertilization] was boosting vegetation in deserts around the planet
http://www.csiro.au/en/News/News-releases/2013/Deserts-greening-from-rising-CO2
Well of course it will rain more over dry areas, we already know that is the reason why sea level rise isnt as high as forecast because of the giant sponge effect. Which is just as well because we learnt today that they wont be able to pump enough water over Antarctica to compensate for rampaging sea levels. Oh lordy, I have only just recovered from gender biased glaciers and the equitable human-ice interface study. My head is hurting again already.
no more climatology let s study modelology… where models are “our” models”,” the” modeis, “their “models , les last models the best models etc…
is it science????
Look at the news: Unusual flooding in Dubaï is ongoing. Severe storms have released rain levels up to 240mm in that region where the mean annual rainfall is about 75mm
Well that is what you get when you build your own islands out of sand in a desert area, even a wet one.
g
The real tragedy here is that there is no discussion of why clouds form, which is not purely a warmth factor. Clouds are not steam.
Cloud formation requires (1) A particulate (dust molecule, algae on the ocean surface, …) (2) in the presence of moisture and (3) the particulate is struck by a galactic ray. This causes clouds to form.
Galactic ray intensity increases when our sun’s activity level decreases, as is evidenced by decreased sunspots as is now the case.
Clouds both relocate moisture in the form of rain, sleet or snow and clouds reflect infrared solar energy away from our home planet earth. Snow, ice and glaciers also reflect more solar energy away from our planet.
All of this will inevitably lead to a cooling of our planet and perhaps a little ice age.
Well actually all you need is a non-hydrophobic surface that has a curvature that is less than some very large number, and somewhat larger than molecular size.
Microbes work quite well as ‘aerosols’, and as for #3, you don’t need to have a CR hit anything like a particulate. Simply hitting something of atomic or molecular size and creating other charged particles will do it. It’s the charged particle tracks that cause condensation in cloud chamber experiments.
You just need the surface tension excess pressure (2t/r) to be less than the hydrogen bonding forces, between H2O molecules. So any landing pad larger than a certain radius works.
G
“HAS revealed?” “Will bring?” Really? This lacks the normal temporizing of CAGW press releases. So much so that it is extraordinary. Does the paper likewise contain extraordinary proof?