Himalayan glaciers and the virtue of reading beyond the headline

My number one pet peeve with the blogosphere is that too many bloggers post on a new report or paper without actually looking at the new report or paper. Bloggers regularly bash mainstream media for lazy reporting then often go ahead and base entire posts solely on newspaper stories. Hypocrisy aside, it is a real shame. Blogs should be an opportunity to examine and debate science and policy issues in more depth than is available in the mainstream media

Case in point, the excitement in the blogosphere (see Roger Pielke Jr) over a new report from the Indian government claiming there is "no evidence" for climate change shrinking Himalayan glaciers. It's worth looking at the actual report.

First, the report is part of a series that "is meant to serve as a basis for informed debate and discussion on critical issues related to the environment." In other words, it is not a scientific assessment conducted by the Indian Government. The report even has a disclaimer that the views contained in the report "are not necessarily endorsed" by the government.

Second, the report is about glaciology. It contains no analysis that could determine, one way or another, if human-induced climate change is contributing to glacier decline. In order to detect a climate change signal, you'd need to combine the glaciology data with climate data and most likely models capable of simulating the evolution of the climate with and without human influence.

Third, despite all this, the report does in fact state that glaciers in the Himalayas have been retreating over the past century.

Glaciers in the Himalayas (India) have been exhibiting a continuous secular retreat since the earliest recording began around the middle of the nineteenth century. Kumdan glaciers, of the Upper Shyok valley, have been the only exception for their periodic fluctuations.

There are plenty of charts and graphs to support the fact that glaciers have been retreating. The author's quibble appears to be over the "alarmist" portrayals of glacier decline in other forums. The first line of the conclusion:

Data that has been generated from the glacier studies, in the Himalayas, over the last 100 years or so, indicates that the glaciers, in the Himalayas, have been, by and large, shrinking and retreating continuously, barring a flip here and there, but the rate of retreat can not be considered as alarming / abnormal, especially in the last decade or so.

The report presents no definition of "alarming / abnormal" (say, in terms of % change) nor does it present data or any analysis to test the notion that the retreat is or is not alarming / abnormal. All we're really left with is that glaciers are retreating and the retreat may or may not be caused by climate change.