Study predicts a significantly drier world at 2 C

January 1, 2018, University of East Anglia
Credit: CC0 Public Domain

Over a quarter of the world's land could become significantly drier if global warming reaches 2C - according to new research from an international team including the University of East Anglia.

The change would cause an increased threat of drought and wildfires.

But limiting global to under 1.5C would dramatically reduce the fraction of the Earth's surface that undergoes such changes.

The findings, published today in Nature Climate Change, are the result of an international collaboration led by the Southern University of Science and Technology (SUSTech) in Shenzhen China and UEA.

Aridity is a measure of the dryness of the land surface, obtained from combining precipitation and evaporation. The research team studied projections from 27 to identify the areas of the world where aridity will substantially change when compared to the year-to-year variations they experience now, as global warming reaches 1.5C and 2C above pre-industrial levels.

Dr Chang-Eui Park from SusTech, one of the authors of the study, said: "Aridification is a serious threat because it can critically impact areas such as agriculture, water quality, and biodiversity. It can also lead to more droughts and wildfires - similar to those seen raging across California.

"Another way of thinking of the emergence of aridification is a shift to continuous moderate drought conditions, on top of which future year-to-year variability can cause more severe drought. For instance, in such a scenario 15 per cent of semi-arid regions would actually experience conditions similar to 'arid' climates today."

Dr Manoj Joshi from UEA's School of Environmental Sciences said: "Our research predicts that aridification would emerge over about 20-30 per cent of the world's by the time the global mean temperature change reaches 2C. But two thirds of the affected regions could avoid significant aridification if warming is limited to 1.5C."

Dr Su-Jong Jeong from SusTech said: "The world has already warmed by 1C. But by reducing into the atmosphere in order to keep global warming under 1.5C or 2C could reduce the likelihood of significant aridification emerging in many parts of the world."

Drought severity has been increasing across the Mediterranean, southern Africa, and the eastern coast of Australia over the course of the 20th Century, while semi-arid areas of Mexico, Brazil, southern Africa and Australia have encountered desertification for some time as the world has warmed.

Prof Tim Osborn from UEA said: "The areas of the world which would most benefit from keeping warming below 1.5C are parts of South East Asia, Southern Europe, Southern Africa, Central America and Southern Australia - where more than 20 per cent of the world's population live today."

'Keeping within 1.5C constrains emergence of aridification' is published in the journal Nature Climate Change on January 1, 2018.

Explore further: Climate change will feed wildfires: experts

More information: Keeping global warming within 1.5 °C constrains emergence of aridification, Nature Climate Change (2018). nature.com/articles/doi:10.1038/s41558-017-0034-4

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Parsec
5 / 5 (9) Jan 01, 2018
Warmer air holds more water than cooler air. Any increase in temperature will increase both the holding capacity of the atmosphere and thus overall precipitation.

This study indicates that not only will the effect of climate change be aridification over a signifigant part of the planet, but indirectly indicates massive increases in rainfall elsewhere (that water has to go somewhere).
BackBurner
1.5 / 5 (11) Jan 01, 2018
Since there's no evidence of this "effect" occurring in the past, and given the fact GCM models referenced by the study have failed to be predictive in any way for the past 30 years, this "study" was a complete waste of time and money.
Noumenon
2 / 5 (12) Jan 01, 2018
This study indicates that not only will the effect of climate change be aridification over a signifigant part of the planet, but indirectly indicates massive increases in rainfall elsewhere (that water has to go somewhere).


So, given the article title propaganda,... more rainfall then on the moon?

'Significant part of the planet' and 'Significantly drier world' should be changed to 'less than one third of earths land surface', and since more precipitation falls over land than ocean, this will only open up more arable land elsewhere. Anyone play with those Chinese toys where you move around the little squares? Human migration has been a game played before.

dfjohnsonphd
2 / 5 (2) Jan 01, 2018
Yes, the air will hold more water as it warms, which puzzles me as to the presumed trend towards aridification. It is not reasonable to believe that rain fall will be limited to coastal zones. We have global warming now and some coastal zones are in drought. I doubt the small number of wind farms are to blame, although they will contribute to changes as their number climbs. Coastal drought has been bad in the southeast U.S. also.

The amount of rainfall in a specific region will depend on changes in global weather patterns - i.e. those large movements of dry or moist air. Location and extent will be very difficult to predict as the warming continues. These changes will determine where the rain falls, not so much general geography. You don't need land and mountains to precipitate a hurricane. Water will continue to evaporate at faster rates the warmer it gets. Aridification should not become a global problem. Atmospheric saturation with water and the resulting storms and floods will.
RichManJoe
4.6 / 5 (9) Jan 01, 2018
For agriculture, too much rain at the wrong time is just as bad as too little rain. This forebodes bad times.
Caliban
4.3 / 5 (6) Jan 01, 2018
It is very simple: it has already been noted that warmer air will hold more water vapor, which is exactly true. Which has been taken to mean by some commenters as equivalent to saying that this simply means more rainfall elsewhere.

If you want to fully understand the effect of a warmer atmosphere, then I'll set it out for you:

1. More water vapor in atmosphere.
2. More water in atmosphere at any given time.
3. More water retained in atmosphere over any arbitrary time period.
4. Longer, more intense episodes of drought, typically in regions so prone.
5. Heavier, more frequent rainfall and more intense, powerful storms in regions so prone.

contd

.
Caliban
4.3 / 5 (6) Jan 01, 2018
contd

Effect number three is the one everyone seems to be missing. It means that a greater volume of H2O will be suspended, on a permanent basis, in the atmosphere at all times. The mere fact that it evaporates does not, by any means, require that the exact same volume will be precipitated back to the surface --nor will it, under this temperature regime.

Regarding this facile claptrap from nonoUnme:

'Significant part of the planet' and 'Significantly drier world' should be changed to 'less than one third of earths land surface', and since more precipitation falls over land than ocean, this will only open up more arable land elsewhere.


25-30% of the land surface IS, BY DEFINITION, a significant portion. The "more arable land" becoming available for use canard is anciently debunked, as only a very small portion of current "vacant' lands are suitable for agricultural use, even in a warming regime.

Noumenon
2.1 / 5 (7) Jan 01, 2018
'Significant part of the planet' and 'Significantly drier world' should be changed to 'less than one third of earths land surface'.


25-30% of the land surface IS, BY DEFINITION, a significant portion


As usual you argue with your own faulty misapprehensions and ghost statements supposedly made by me. No where did I say that 20-30% of land surface is not significant.

The two quoted posts refer to 'planet' and 'world' without quantification, whereas the study refers to land surface with quantification. My revised statement is more accurate because it doesn't make use of subjective phrases like "significant", which could mean anything from a bit to nearly all.

I made this distinction to follow up with my point about migration required.

I had rated Parsec a 5, so did not disagree with his post.

Noumenon
2.1 / 5 (7) Jan 01, 2018
So you're basically objecting to my more quantified statement as opposed to those quoted. Typical liberal AGW alarmist.

only a very small portion of current "vacant' lands are suitable for agricultural use, even in a warming regime.

Who spoke of 'current lands' and ancient farming practices?
Caliban
4.3 / 5 (6) Jan 01, 2018
'Significant part of the planet' and 'Significantly drier world' should be changed to 'less than one third of earths land surface'.

25-30% of the land surface IS, BY DEFINITION, a significant portion


" 'As usual you argue with your own faulty misapprehensions and ghost statements supposedly made by me. No where did I say that 20-30% of land surface is not significant.' "

Not at all. The quote is from your own comment, not the article. Good of you to point out the non-existence of any substance within it, though.

contd
Caliban
4.3 / 5 (6) Jan 01, 2018
contd

The two quoted posts refer to 'planet' and 'world' without quantification, whereas the study refers to land surface with quantification.


Technically correct, if a little broad. But, since the direct effects of increased precip AND drought will affect land-bound Humanity, it amounts, as usual with you, to hair-splitting, as illustrated in your further response:

My revised statement is more accurate because it doesn't make use of subjective phrases like "significant", which could mean anything from a bit to nearly all.


In order to set up your further inanity:

I made this distinction to follow up with my point about migration required.

I had rated Parsec a 5, so did not disagree with his post.


Which is even more cause for concern, regardless of your flippancy. If you --though I suspect not-- meant to portray this as a source of concern, then you have my apology.

If so, then why not more explicitly?
Noumenon
2.1 / 5 (7) Jan 01, 2018
Your conjecture was that I didn't think that 20-30% land surface was 'significant'. I never stated anything of the sort, and had I thought this, would not have subsequently mentioned the expectation of human migration.

If so, then why not more explicitly


Indeed, why not make it more explicit by using my quantified phraseology rather than, 'significantly drier world'?

I accept your apology, the thread does not need to be longer on account of this.

BackBurner
3.8 / 5 (4) Jan 02, 2018
I'd just like to point out that the word "significant" only has meaning in the context of a statistical analysis. In other usages it's just an expression of the author's opinion and associated value system.
Noumenon
1.8 / 5 (5) Jan 02, 2018
Even then it is quantifiably defined.
dfjohnsonphd
2.5 / 5 (4) Jan 02, 2018
Returning to the science......

One thing most have not addressed is that high humidity should produce thick clouds, which will shield the planet from direct sunlight. If a global cloud cover is produced, there might by cycles of warming and cooling as the cloud cover builds and thins. Anybody have an idea on that one?
avandesande2000
1 / 5 (7) Jan 02, 2018
Global cooling is responsible for desertification and all historical records point to this. What do you trust, history or the models of scientists looking for government funding?
Caliban
5 / 5 (4) Jan 02, 2018
Indeed, why not make it more explicit by using my quantified phraseology rather than, 'significantly drier world'?

I accept your apology, the thread does not need to be longer on account of this.


Sure.

However, this misunderstanding does not extend to your glib claim about additional arable land becoming available, as you well know, and thus your haste to throw the baby out with bath water in accepting my apology.

Since I know from past experience that you will not directly address your error, or offer any credible research citations to support the implied claim, I'll not waste any time engaging in a hair-splitting contest with you.

Also, this is the last time I will make an apology for my "misunderstanding". When you post such vaguely worded and insinuating comments, you may be certain of sharp criticism from myself and others, as I, at least, understand that this is your preferred modus operandi.
Caliban
5 / 5 (7) Jan 02, 2018
Global cooling is responsible for desertification and all historical records point to this. What do you trust, history or the models of scientists looking for government funding?


We trust both models and the historical and paleoclimate evidence.

All of which says you are both wrong and a liar.
adam_russell_9615
5 / 5 (4) Jan 02, 2018
I dont see that the atmosphere holding more water would lead to more rain. Rain is the inability of the atmosphere to hold the water it has. If it can hold more water wouldnt that mean less rain?
Zzzzzzzz
3.4 / 5 (5) Jan 02, 2018
I dont see that the atmosphere holding more water would lead to more rain. Rain is the inability of the atmosphere to hold the water it has. If it can hold more water wouldnt that mean less rain?


Yes, that is correct - despite the verbal diarrhea brain dead dumb pharks like Noumenon might spew.
MR166
1.6 / 5 (7) Jan 02, 2018
"I dont see that the atmosphere holding more water would lead to more rain. Rain is the inability of the atmosphere to hold the water it has. If it can hold more water wouldnt that mean less rain?"

"Yes, that is correct - despite the verbal diarrhea brain dead dumb pharks like Noumenon might spew."

Thanks for the insite fellows. With no increase in rain but increased absorption I could see the atmosphere continuing to absorb water until fish no longer need to be constrained to the sea.
MR166
2.1 / 5 (7) Jan 02, 2018
It will be dryer everywhere on earth except where it is wetter.

Yet another brilliant AGW prediction that is worth every bit of the $100 Billion of climate grant monies.
Noumenon
1.7 / 5 (7) Jan 02, 2018
I dont see that the atmosphere holding more water would lead to more rain. Rain is the inability of the atmosphere to hold the water it has. If it can hold more water wouldnt that mean less rain?


Yes, that is correct - despite the verbal diarrhea brain dead dumb pharks like Noumenon might spew.


He is responding to another poster, so clearly you don't have reading comprehension. It is clear that you're a child, a troll, an idiot, or all three. I will put you on ignore, mainly because you never actually said anything to me of substance.
shadybail
1.8 / 5 (5) Jan 02, 2018
"Yes, that is correct - despite the verbal diarrhea brain dead dumb pharks like Noumenon might spew."

So...ad hominem is an acceptable response on this site? Is this Yahoo? It's good to know that every time I don't understand something or disagree that I can just attack the poster. Who needs learning, yes?

@Noumenon, I put him on ignore too.

MR166
1.8 / 5 (5) Jan 02, 2018
This paper totally disregards the fact that despite (or because of) an increase in CO2 over the the years the deserts are actually greening. Empirical data once more overrides the massaged models.
Zzzzzzzz
3.7 / 5 (3) Jan 02, 2018
I dont see that the atmosphere holding more water would lead to more rain. Rain is the inability of the atmosphere to hold the water it has. If it can hold more water wouldnt that mean less rain?


Yes, that is correct - despite the verbal diarrhea brain dead dumb pharks like Noumenon might spew.


He is responding to another poster, so clearly you don't have reading comprehension. It is clear that you're a child, a troll, an idiot, or all three. I will put you on ignore, mainly because you never actually said anything to me of substance.

Dream on, dumb phark, as only the brain dead can. Fecal regurgitation will never attract substance.
Zzzzzzzz
5 / 5 (3) Jan 02, 2018
"Yes, that is correct - despite the verbal diarrhea brain dead dumb pharks like Noumenon might spew."

So...ad hominem is an acceptable response on this site? Is this Yahoo? It's good to know that every time I don't understand something or disagree that I can just attack the poster. Who needs learning, yes?

@Noumenon, I put him on ignore too.


FanBoys of Trolls.....how touching.
Noumenon
2.3 / 5 (6) Jan 03, 2018
@shadybail,.... if one is a conservative or libertarian at physorg they are trolled rated, lied about, and generally verbally abused. The site administrators actively support and participate in this corrupt behaviour as I can attest from posting here for a decade.

The majority of posters here are left leaning politically and think of libertarianism as a threat rather than as an alternative political philosophy. Such a mentality can only be the result of indoctrination.
shadybail
1.8 / 5 (5) Jan 03, 2018
"left leaning politically" You mean welfare recipients, Hollywood libs and college students, yes? Sounds to me like the trolls are frustrated because they can't attack the authors of these papers directly. Instead, they rely on attacking the people who post here.

I notice they give you (Noumenon) a lot of grief. If trolls do this to you, it means to me that you are generally correct. I take solace in knowing they could never do this to you face to face. Such is the way of keyboard cowards.
wkingmilw
5 / 5 (2) Jan 03, 2018
We'll be luck if we can stop at 5*
leetennant
5 / 5 (6) Jan 03, 2018
Do not feed the astroturfing paid anti-science trolls.
they are paid by jim hoft of gatewaypundit.


Well, yes and no. There's no point in abusing them or getting into a yelling war. But they're paid to astroturf to give the impression there's some controversy to the science. By combatting the substance of their posts, we're able to correct that incorrect impression.

That's why we should engage but strictly in terms of content. If their posts have no content (and they frequently don't) then we should point that out calmly and politely so the average punter can see the emperor has no clothes.

Also, some of them are genuine and have been here for a while. It's obvious that Noumenon for example is for real but also thinks that science is somehow against his personal philosophy because it keeps contradicting it. No point in yelling at him either.
Noumenon
1 / 5 (4) Jan 04, 2018

While we're at it, it's better to be substantive rather than posting drive-by characterizations the sole purpose of which is to render dishonest impressions of others instead of objective counter points.

For example, ....

[Noumenon] thinks that science is somehow against his personal philosophy because it keeps contradicting it.


....what specific science is contradicted by my supposed philosophy? What are you even referring to?
barakn
3.7 / 5 (3) Jan 04, 2018
So...ad hominem is an acceptable response on this site? .... "left leaning politically" You mean welfare recipients, Hollywood libs and college students, yes? -shadybail
Here's a quick learner. Holier-than-thou to gutter in two posts.
TrollBane
1 / 5 (1) Jan 06, 2018
"So...ad hominem is an acceptable response on this site? "
It's not an ad hominem argument, not a claim that personal characteristics rather than logic or evidence disprove a claim. It's a description of the motivated blarney posted by trolls and how irrelevant it is.
TrollBane
1 / 5 (1) Jan 21, 2018
"He is responding to another poster, so clearly you don't have reading comprehension. It is clear that you're a child, a troll, an idiot, or all three. I will put you on ignore, mainly because you never actually said anything to me of substance. "

How about a slow clap for getting "you're" right?

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