Saturday, November 14, 2009

Himalayan Glaciers - Science vs the IPCC

There has been a little controversy recently over the state of glaciers in the Himalayas. There has been much talk about how the glaciers in the region are melting, and thus threatening the water supplies for many nations fed water through rivers that start in those mountains. The stories have dramatized the retreat of the glaciers and used the threat of glacier disappearance, which is tied in the stories to AGW, as means of highlighting the need for remedial action.

However the placers where these glaciers are found are difficult to access, in many cases, and more particularly have been hard to get to on a consistent basis, so as to develop a record of exactly how fast the glaciers are, and have been retreating. For if we accept the existence of the Little Ice Age, and that glaciers around the world have been warming as the globe has warmed since then, the question becomes one of whether the glaciers are, in fact, accelerating.

Rates of retreat of the Altay glaciers of the Pamir in the nineteenth and twentieth centuries (From Grove – The Little Ice Age)

Grove noted, however, (in 1988) of the Altay that
It is possible that retreat will not continue unbroken, for latterly positive mass balances have been measured on the five Aktra glaciers.

And just recently there have been other reports of glaciers – in this case some 230 of them around the Karakoram mountains of the western Himalayas – also growing.
"These are the biggest mid-latitude glaciers in the world," John Shroder of the University of Nebraska-Omaha said. "And all of them are either holding still, or advancing." . . . . In the Karakorams, the uptick in glacier mass has come with a welcomed perk. The mighty Indus River, which flows out of China and nourishes northern India and much of Pakistan has experienced an increase in discharge.
Given therefore that there appear to be some discrepancies between the dramatic conclusions that are being drawn, and the actual facts, it is interesting to read a report from the Indian Ministry of Environment and Forests where individuals have, over the years, actually gone out to a number of different glaciers feeding down into India, and measured the location of the snouts of the glaciers, and thus been able to determine, over time, how the glaciers are behaving. And their conclusion has been
Himalayan glaciers, although shrinking in volume and constantly showing a retreating front, have not in any way exhibited, especially in recent years, an abnormal annual retreat, of the order that some glaciers in Alaska and Greenland are reported.
To explain that a little more clearly, the studies have shown that there has been no increase in the average speed at which the glaciers are retreating, and that the acceleration that is trumpeted by the IPCC and its followers, does not exist.

Now this news has not been received with enthusiasm by the IPCC. Given that the report discusses actual measurements at the glaciers, beginning as far back as the mid-nineteenth century (see graph above) and going beyond just measuring the position of the snout, to geophysical measurements of the ice thickness which began in 1965. The report details glaciers, such as the Chong Kumdan, which by 1958 had advanced sufficiently far as to threaten to block the Shyok river. And it explains how and when different techniques were used to establish the mass balance of different glaciers.

The report illustrates some of the results that were found in the first decade of study as follows:

As the techniques for analysis have become more sophisticated, so it has been possible to look at the mechanisms by which the glaciers gain and lose mass over period of a year. Generally the glacier gains mass from the snows of winter, and loses it due to melting in the warmer weather of the summer. Given the conditions in the Himalayas it was difficult to make that determination (about winter growth) until satellites came along to provide winter access for observation.

From these studies the report notes
Studies have revealed that the major factor for the negative regimen of the glaciers in the Himalayas is the relatively less snow precipitation during the winter (rather) than enhanced glacier melting in summer.
In other words it is not the global warming that is causing the glaciers to retreat, (the summer melting) but rather that there is not as much snow falling on them in winter. (Which is similar to the cause of the glacier retreat on Mount Kilimanjaro). The amount of relative melt is of concern in India, not just because of the water that it provides for consumption, but also because the water provides motive energy for hydro-electric power generation.

Source Index Mundi.

The report has been criticized because of the small sample size, but it details the technology used, and explains why the models developed in the Alps are not suitable. It has included measuring the melt water
it becomes imperative that round the clock monitoring of water discharge, during the entire melt season- June to September be carried out at as many glaciers as is possible.

Various teams, which are carrying out glaciological studies in the Himalayas, have carried out the monitoring of the glacier melt streams either by erecting a weir, across the melt stream, downstream of the snout; or installing an Auto stage recorder.

These are generally established where the stream course is braded or spread out so that data recording is manageable even at the height of the melt season, when the discharge rate goes up many folds In some cases usage of current meter has also been undertaken. Considerable data has so far been generated and various prediction models devised, yet due to rather poor response from the user agencies this data has remained, by and large, un-tested.
It should be noted that if a glacier stops melting, then the amount of water that it supplies to the rivers, and to the folks downstream depending on that water (particularly when the monsoon fails) will decline.
For the assessment of the glacier ice thickness and the volume thereof, TTS, in their guide lines, had suggested the usage of a rating curve based upon their work in Alps. This rating curve was, however, found to give erroneous results. A rating curve that was suitable for the conditions in the Himalayas was evolved by assessing the thickness of the glacier ice in some selected glaciers by geophysical methods: electric resistivity, magnetic and seismic (refraction) techniques followed by thermal/rotary drilling for confirmation of the same.
The report, in short, provides a detailed and rational explanation of what was done, and the consequent results. That it does not meet with the approval of the head of the IPCC is not surprising, but it is perhaps an example of the way in which this debate is being carried out that on one side you get a detailed set of scientific measurements and on the other (bearing in mind that this is a government agency issued report, backed by a minister) you get, from the IPCC
Pachauri dismissed the report saying it was not "peer reviewed" and had few "scientific citations".

"With the greatest of respect this guy retired years ago and I find it totally baffling that he comes out and throws out everything that has been established years ago." . . . . .schoolboy science.
Scientific measurement versus ad hominem attacks, sadly one can anticipate which side the mainstream media will accept.

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