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back to article Study finds water cycle accelerating with warming

Climate models are inaccurate, but not in a comforting way: that’s the conclusion of an ocean salinity study conducted by CSIRO and the Lawrence Livermore National Laboratory, which indicates that changes in the water cycle are running faster than models predicted. Based on the relationship between salinity, evaporation and …

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Anonymous Coward

Salinity provides a good proxy for both rainfall and evaporation,

Herein lies many of the problems of particular areas of science.

Measuring the actual item to be studied is too hard, so we measure something else. While that may be accurate and convenient, it may not be, or it maybe in some areas but not in others - the added indirection makes the science less certain. At least, the data might be certain, but it relates less to what we were trying to study. We end up with lots of interpretation based on very little direct evidence.

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Anonymous Coward

Re: Salinity provides a good proxy for both rainfall and evaporation,

The other issue stems from how the subject is taught to the next generation.

They get taught, to Determine A and B, measure C.

What sometimes gets lost in translation is that the measurement of C is 99.9% accurate for A and only 80% accurate for B, Where you need to measure D, E and F to determine the other factors.

They may be taught the theory, but a lot will ignore it, going for the easy out.

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Re: Salinity provides a good proxy for both rainfall and evaporation,

"We end up with lots of interpretation based on very little direct evidence"

Welcome to experimental physics! I know it seems like "bad science" when scientists rely on proxies, primarily because it can be hard to understand why and how proxies are used, but all of the things we can "see" directly have been observed already, so the newer things we look at have to be viewed indirectly. Ergo proxies, whether that be new particle discoveries, galactic interactions, climate, or something else.

I find it odd that if ppl who have a political view on climate modelling/change read a story based on proxy measurements they decry them as inaccurate, but then "ooh" and "ahhh" over a new particle discovery which has been discovered by measuring proxies (not referring to the OP, just in general).

Salinity isn't a bad proxy btw - the salts have a tendancy to stay where they are, there's a finite amount of water in the water cycle which has a finite number of states, so measuring the salinity gives you a decent picture of where the water is at any given time.

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Bronze badge

Re: Salinity provides a good proxy for both rainfall and evaporation,

> The other issue stems from how the subject is taught to the next generation.

That's right. Damn kid scientists lack rigor and won't stay off my lawn.

Not like our generation, eh? Igor, fetch me the beaker of phlogiston and a flask of the luminiferous ether. I feel a thunderstorm coming on.

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Facepalm

See icon.

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Silver badge

And of course the water cycle is the planets thermostat. Hotter=more vapour=more cloud carrying heat up to radiate to space = more cold rain falling to cool planet surface and sea and more cloud shielding the earth from the sun.

Completely obliterating the effects of and CO2 change by and large.

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Silver badge
Facepalm

Close, but no cigar

Clouds are reflective of both optical and infrared radiation. More vapor = more clouds. More clouds = higher albedo (heat&light reflected to space without reaching the ground). Which results in lower temperatures at the surface ultimately. But in the short term warmer as the clouds also reflect what heat is already on the ground back down. You see this in the desert where the nighttime temperatures drop precipitously due to lack of cloud cover.

Not sure where they're going with this. Looks like a negative feedback loop.

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FAIL

Water vapor is a greenhouse gas. It is a positive feedback, not a negative one.

http://en.wikipedia.org/wiki/Greenhouse_gas#Role_of_water_vapor

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@Silly Beggar

Clouds are water = solid, not gas...

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Thumb Down

True only for the age of the dinosaurs

... and unfortunately not true for the unusual era we are living in, with ice at both poles.

For most of Earth's history, there was no ice at sea level anywhere on the planet, and the climate stability model was very straightforward. It was also very warm - Antarctica had a temperate climate, and the tropics would have been too hot and humid for large mammals like people to survive.

Ice creates instability. Cooler - more ice - more reflected sunlight - cooler, or warmer - less ice - less sunlight reflected - warmer. Positive feedback, not negative. But this too is a gross over-simplification. More heat nearer the equator and more water vapour from the oceans may result in more snowfall over the poles, resulting in more ice even if it's warmer ice. Or not. This all depends on the actual atmospheric circulation patterns. Also ice is a step-discontinuity. Below 0C, you get snowfall, above 0C, you get rainfall, and the transition between water and ice releases a lot of energy.

Ice is just one of the reason why climate modelling for the present is particularly difficult.

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Facepalm

Re: @Silly Beggar

@amanfromearth

Which bit of "water vapor" are you struggling with?

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Anonymous Coward

yada yada yada

you'd think someone would have thought to put this brilliant observation, that a water cycle exists, into a model...

oh wait, they did,

never mind.

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Pint

Accelerating the water cycle = more fresh water

That's what the cycle does: it carries evaporated seawater over land and deposits it as rain and snow. So more of this is a good thing for freshwater resources. This is the greening of Africa.

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Facepalm

Re: Accelerating the water cycle = more fresh water

Did you miss the bit where he says drier areas will get drier? If the article is correct - Africa will get dryer, not greener.

Just as well they can drill for that huge groundwater resevoir, eh BBC?

Headslaps all round.

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Re: Accelerating the water cycle = more fresh water

Assuming someone will build a megaproject water pipeline spanning thousands of miles to get that extra water from the wetter areas to the dryer areas, through some of the poorest countries in the world and in some of the harshest conditions. Since us Brits (who aren't short a bob or two) can't manage to build a pipeline from the north to the south through a few hundred miles of well-tamed farmland, I'd say that plan was SOL, wouldn't you?

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Water vapour is a greenhouse gas

[quote]And of course the water cycle is the planets thermostat. Hotter=more vapour=more cloud carrying heat up to radiate to space = more cold rain falling to cool planet surface and sea and more cloud shielding the earth from the sun.

Completely obliterating the effects of and CO2 change by and large.[/quote]

LOL. Such extreme ignorance. Water vapour is a greenhouse gas - more so than carbon dioxide.

http://www.guardian.co.uk/environment/2010/jan/29/water-vapour-climate-change

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haha humans are fucked

and can be phased out now

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Joke

Not a global effect...

This research applies to everywhere except the UK...

'cos it doesn't allow for droughts, hosepipe bans, and flood warnings in the same week.;)

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Re: Not a global effect...

It's almost as if "changes in the water cycle are running faster".

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g e
Silver badge
Meh

So ?

Is this why the Himalayan glaciers are also going in the opposite direction to the doomsayers' predictions?

Perhaps the evaporate is just ending up there.

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Re: So ?

They're not.

HTH.

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Re: So ?

They are. You need to read more.

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Anonymous Coward

Re: So ?

are not!

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Silver badge

Re: So ?

There ARE no glaciers in the Himalayas. No-one can prove it. Smog contains delicious vitamins and CO2 is life.

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Pint

Re: So ?

co2 IS life, along with water and the lovely radiation from the sun it's all thats keeping us from looking like mars.

Oxygen is obviously pretty good as well for the stupid animal things, but they're just parasites living off of other lifeforms and have been around a lot shorter timevise.

do you know just how many people die each year from dihydrogen monooxide related causes?

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Boffin

As usual when it comes to scientific matters,

things are more complicated than they seem at first glance. Claims - often as in the case of g e's posting above, ensconced in rhetorical questions - to the effect that «the Himalayan glaciers are also going in the opposite direction to the doomsayers' predictions» fail, whether by design or by ignorance, to understand the complexity of the situation. Below the abstract of an article, entitled «The State and Fate of Himalayan Glaciers» (http://www.sciencemag.org/content/336/6079/310.abstract'), recently published in Science. Perhaps we all need to read more ?...

«Himalayan glaciers are a focus of public and scientific debate. Prevailing uncertainties are of major concern because some projections of their future have serious implications for water resources. Most Himalayan glaciers are losing mass at rates similar to glaciers elsewhere, except for emerging indications of stability or mass gain in the Karakoram. A poor understanding of the processes affecting them, combined with the diversity of climatic conditions and the extremes of topographical relief within the region, makes projections speculative. Nevertheless, it is unlikely that dramatic changes in total runoff will occur soon, although continuing shrinkage outside the Karakoram will increase the seasonality of runoff, affect irrigation and hydropower, and alter hazards.»

Henri

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Stop

Some reading is sometimes worse than no reading...

"Is this why the Himalayan glaciers are also going in the opposite direction to the doomsayers' predictions?"

-and-

"They are. You need to read more."

It helps if YOU read the article - not "the Himilayahs" - rather the "Karakoram mountain range," which depending on your perspective / definition of "the Himilayahs" is either a part of the greater Himilayahs a general concept or is not part of the Himilayahs range...

Or to put it another way generalizing Karakoram as the Himilayahs would be like observing that it is raining in London and saying that it is rainy in Europe. It is in fact rainy in part of Europe, but may or not be raining in all of Europe...

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