Freshwater flow dominated by monsoon rains rather than glacier run-off.
Reposted from naturenews (nature.com)
Richard A. Lovett
Although global warming is expected to shrink glaciers in the Himalayas and other high mountains in Central Asia, the declining ice will have less overall impact on the region’s water supplies than previously believed, a study concludes.
It’s an important finding, says Richard Armstrong, a climatologist at the US National Snow and Ice Data Center in Boulder, Colorado, who notes that the Intergovernmental Panel on Climate Change had previously predicted dire restrictions on water supplies in Asia. “There clearly were some misunderstandings,” he says.
The researchers behind the latest study began by calculating the importance of meltwater in the overall hydrology of five rivers: the Indus, the Ganges and the Brahmaputra in India, Pakistan and Bangladesh, and the Yellow River and the Yangtze in China1. The authors found that meltwater is most important to the Indus, with a contribution roughly 1.5 times that from lowland rains. In the Brahmaputra, meltwater flow is equivalent to only one-quarter of the volume supplied by lowland rainfall, and, in the other rivers, it forms no more than one-tenth of the input.
Furthermore, the study found that in the Indus and Ganges basins, glacial ice contributes only about 40% of the total meltwater, with the rest coming from seasonal snows. In the other three rivers its contribution is even lower.
High and dry?
That’s important, says Walter Immerzeel, a hydrologist at FutureWater in Wageningen, The Netherlands, and lead author of the study1, because Asian rivers are fed by three sources: rain, snow melt and melting glaciers.
The first two are driven by current weather patterns, because rains fall either as water or as snow that will later melt. The last is a carry-over from the build-up of glaciers in prior centuries. As the glaciers shrink, their contribution will also decline until the glaciers have either melted entirely, or stabilized at smaller sizes.
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Seems like this would be good news for policymakers, right? Less worry about how people will get freshwater. But look at this quote:
Great. No matter what the evidence shows, it is mounting evidence for worrying about climate change.
One good thing about this cAGW scare is that people are again discovering things that are (or should be) obvious. It should have taken the average “hydrologist” a few minutes to determine these numbers, they are hardly secret. Even my own local river has its origin at glaciers but is mostly filled by precip. Not rocket science.
Concern is not the same as worry. I am not getting a sense of urgency from this guy. He will fail to get further funding if he doesn’t change his message.
“There clearly were some misunderstandings,” he says.
Exaggerations, lies, falsifying data, totally making things up, yes…..
……..misunderstandings, no
Shhh. Don’t tell anyone but the glaciers are probably more dependent on monsoons than temperature, too.
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The problem they have over there is a falling water table.
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Can you imagine that these people design airplanes for example?
“The wing will be 30 meters wide – or maybe just 13?”
Once one of those university creature boasted that most of the scientists (in universities and governmental institutions) are leftist, trying to claim intellectual supremacy. Now I understand why such people gather in public sector: with their junk work, they would not survive in a private sector for a single month.
I don’t think glaciers really ‘stabilize’, do they? They either grow or shrink.
Assuming the importance of water in glacial runoff was as big as first thought. Did they ever think about the following situations:
Glaciers begin to increase in size, resulting is less run off
Glaciers grow enough to displace the populace which depends on the glacier MELTING.
To trivialize the worst case in both scenarios in either case, they populace has the same end result – MOVE or die. Which is a cycle which has happened throughout human and natural history. We just seem to have forgotten the fact that we were once nomadic and moved or died with natural cycles in the weather/climate/environment…
I assume Al Gore will add this new information into his slides ASAP. /sarc
Wouldn’t they have a greater problem if the glaciers weren’t retreating and creating runoff? Wouldn’t that create drought conditions as a percentage of each years snowfall becomes glacial ice rather than meltwater (as it is today)? I can’t understand the logic of glacial retreat=drought. In general I would assume any given glacier is either retreating or advancing for a variety of reasons. The idea that there is some magical IPCC “steady state” is a complete fallacy.
Isn’t one of the GW predictions increased precipitation? That would mean more rain and snow. This is called negative feedback , not “tipping points”. I don’t think we need to worry about these glaciers continuing to decline for the next 350 years.
BTW, I saw a link to a “bildenberg” site on the Guardian.co.uk. and found an interesting item on the agenda for the recent meeting in Spain.
http://www.bilderbergmeetings.org/meeting2010.html
The Conference will deal mainly with Financial Reform, Security, Cyber Technology, Energy, Pakistan, Afghanistan, World Food Problem, Global Cooling, Social Networking, Medical Science, EU-US relations.
Global Cooling !?
Probably just a stunt to increase attendance. 😉
So if glaciers were in a growth phase the flow of the Indus could reduce by over 50% ?
Have the climate hysterics been right about anything yet? I can’t think of a single thing. Anybody have an example where they’ve been right? I’d like to know.
Not only does this make sense but it brings these drainage basins into line with most other around the wold. Sitting here on the banks of the Bow River one is made ever so aware to the differential contributions from melting glaciers and regional weather.
JurajV, I second that, but, maybe not a month, more like a week.
Absolute useless tossers they are!
Sooo….if we were to stop this rampant global warming, and the glaciers stopped melting, the effect would be exactly as if the glaciers had all melted away??
Brilliant! Those people dependent on the rivers can’t win!!
An important part of this is the water table. Water comes in and water goes out. How about a discussion on water use (water goes out)? My understanding on India is the increasing dependence by peasants on government constructed infrastructure to draw water, rather than relying on their own means as in the past. If this is the case, blaming lack of water on climate change is about all the government can do.
The worry, fussing, and fighting is entirely an artificial construct made out of whole cloth, something humans are very prone to do. The energy that drives oscillations comes from imbalance, not “stability”. When we try to intervene either through mitigating climate change by putting dust in the air, or meddling with specie increases and declines, we run the risk of upsetting and even destroying the very flora and fauna as well as marine life we are trying to save. It has taken millions of generations to adjust to these oscillations and their extremes. There are even species that wait for the extremes in order to cycle. To artificially adjust this pattern is to prove mankind to be very foolish.
I’ve always been baffled by the intrinsic contradiction of this glacier argument. They are arguing that if the glaciers melt, there will be an end to the meltwater. But they don’t seem to consider that if the glaciers stop receding, there will in fact be LESS meltwater! So the key is precipation changes, not temp changes. But the glaciers do one good thing: they provide meltwater also after the main snow melt season. That’s a slightly more convincing argument. But probably too complicated for Gore-style scare stories.
Why do everybody insist on the idea that, as the glaciers shrink, less water will be available? It’s exactly the opposite. As the glaciers shrink, lots of water become available. Because the glacier shrinks when the ice turns into water. If it didn’t shrink, less ice would turn into water and less water would be available. Shrinking glaciers are a GOOD thing for the water suply – of course, as long as they don’t completely run out of ice. But many centuries have to pass before we reach that point.
A quick review of the relevant literature on line shows that everything in this article was previously well known and thoroughly discussed. In fact the contribution of rain and glacier was specified down to cubic meters per month going back to the 1960’s. Temperatures are most significant to the Indus, it being most reliant upon melting glaciers and traverses a relatively dry area. Interestingly enough, none of the traditional hydrological literature, which is more concerned about water utilization, is overly concerned about AGW. That is because global warming would increase river flow. In fact of greater concern is the misuse of watersheds by mankind. Something the Nature article does not address. For example, in discussion of The Indus, I found:
“Further, prolonged human interference with natural drainage and deforestation in the Himalayan foothills have led to a drop in groundwater levels and a further loss of vegetation. It appears that in prehistoric and earlier historic times the middle Indus region was more wooded than it is at present: accounts of Alexander the Great’s Indian campaigns (c. 325 BCE) and records of Mughal hunts in the 16th century and later suggest considerable forest cover.”
Screwing up watersheds has a very significant effect on glaciation, as we all know from the shrinkage of the Kilimanjaro glacier. This something that can and should be rectified.
Another item of note is there do not seem to be any anomalous flow patterns in the last few decades in spite of the claimed AGW.
There are other more evident and more important shrinkages now in the world to care about than supposedly shrinking glaciers in forgotten lands beyond the horizon. Don’t you think so?
Who wets the most, a shrinking glacier or a global warmist?
Actually, this is a very good example of how you can interpret data totally backwards:
Can you imagine that these people design airplanes for example?
“The wing will be 30 meters wide – or maybe just 13?”
The thing is, will the plane fly if the wings are only 13 meters wide – or will it crash?
It’s like, “is the glass partly empty, or is it nearly full”?
If you believe completely in your computer models, like the AGC supporters do, you can be confident that you know the whole truth. But if you’re a skeptic – like I am – I think there’s still reason to be a bit worried about the glacier melting data.