Himalayan glaciers: how the IPCC erred and what the science says

Comments 1 to 9:

1. Kooiti Masuda at 09:52 AM on 29 October, 2010
   I am afraid both the current versions of "Basic" and "Intermediate" need some revision. I think that the issue of the Himalayas proper and the issue of the central Asian highlands including the Himalayas should be distinguished. I have made some comments on the blog article of "Himalayan Glaciers, Wrong Date, Right Message. I am tempted to write clarification myself, but, regrettably, I cannot promise it.
   
   At least, Kehrwald et al. (2008) should not be used as a reference for the issue of population who depend on glaciers. Kehrwald et al. just quoted from IPCC AR4 WG2 (including the errorneous "prediction") and Barnett et al. (2005) about that. Kehrwald's paper seems to be a good reference about the mass balance of certain glaciers they studied.
   
   Also, the word "IPPC" in the title should be "IPCC".
2. Daniel Bailey at 10:02 AM on 29 October, 2010
   I'm glad to see, at least in the Intermediate version, that WG1 and WG2 are differentiated. There exist those that would invalidate all of WG1 on the basis of, effectively, a typo in WG2.
   
   The Yooper
3. Matthew at 20:18 PM on 27 January, 2011
   This says they are not retreating because of climate-change.
   
   http://www.telegraph.co.uk/earth/environment/climatechange/8284223/Himalayan-glaciers-not-melting-because-of-climate-change-report-finds.html
4. JMurphy at 20:58 PM on 27 January, 2011
   From the Telegraph report :
   
   Their report, published in the journal Nature Geoscience, found the key factor affecting their advance or retreat is the amount of debris – rocks and mud – strewn on their surface, not the general nature of climate change.
   
   Glaciers surrounded by high mountains and covered with more than two centimetres of debris are protected from melting.
   
   Debris-covered glaciers are common in the rugged central Himalaya, but they are almost absent in subdued landscapes on the Tibetan Plateau, where retreat rates are higher.
   
   From the report itself :
   
   More than 65% of the monsoon-influenced glaciers that we observed are retreating, but heavily debris-covered glaciers with stagnant low-gradient terminus regions typically have stable fronts.
   Our study shows that there is no uniform response of Himalayan glaciers to climate change and highlights the importance of debris cover for understanding glacier retreat, an effect that has so far been neglected in predictions of future water availability,or global sea level.
   
   
   Interesting contribution which provides more detail. Hardly "they are not retreating because of climate-change" !
5. Roh234 at 14:00 PM on 15 September, 2011
   Its black carbon deposited by pollution that plays the major role in the melting. The article does imply that the greenhouse effect does play a role but the majority of the melting is caused by black carbon deposits.
   
   http://www.nasa.gov/topics/earth/features/carbon-pole.html
   Response:

   [DB] Apart from Sphaerica's fine response, you may wish to read up a bit on Himalayan Glaciers.  Your NASA reference dates from 2009.  Glaciologist Mauri Pelto has a list of blog posts on glaciers worldwide here.  The Himalayan posts are all 2009-2011.  Mauri indicates that fresh snowfall on the glaciers tends to blunt the impacts of black soot on the glaciers (due to their altitude, they retain much of the fresh snow year-round in their accumulation zones).

   Despite this, many such as the Gangotri Glacier have receded heavily over the past century:

   

6. Sphaerica at 14:11 PM on 15 September, 2011
   5, Roh234,
   
   Wrong.
   
   From the article you linked (emphasis mine):

   "Tibet's glaciers are retreating at an alarming rate," said James Hansen, coauthor of the study and director of NASA’s Goddard Institute for Space Studies (GISS) in New York City. "Black soot is probably responsible for as much as half of the glacial melt, and greenhouse gases are responsible for the rest."

   That says black soot gets up to but not more than half. This does not equal "the major role" and may in fact be at best equal to (but probably secondary to) greenhouse gases.
   
   The concluding line?

   "Reduced black soot emissions, in addition to reduced greenhouse gases, may be required to avoid demise of Himalayan glaciers and retain the benefits of glaciers for seasonal fresh water supplies," Hansen said.

   Which means the problem is even worse, because we now have two problems to fix instead of only one.
7. scaddenp at 14:31 PM on 15 September, 2011
   Of course, black carbon and CO2 are often from same source. You might also note that black carbon has much lesser role on other ice melts (distance from asia). Also note that effect of black carbon is short-lived while CO2 is very much longer.
8. scaddenp at 14:33 PM on 15 September, 2011
   You might also like to look at its soot if you are interested in the science rather than repeating skeptic talking points.
9. CBDunkerson at 21:54 PM on 15 September, 2011
   Yeah, I always love the 'no it is soot' argument.... even if it were true, the solution would be exactly the same: transition away from the coal power plants which are the primary source of increasing atmospheric CO2 AND soot. Somehow 'skeptics' never seem to make that connection.

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