As far as current global observations are concerned, Hansen cites both the decline of Arctic sea ice and the worldwide retreat of mountain glaciers as causes for major concern.

CNN: Carbon dioxide levels already a danger

In theory, that will cause rivers fed by Himalayan glaciers to flood first, then will dry up once the glaciers retreat, endangering tens of millions of people in lowland Bangladesh.

FORBES: The New Military War Against Climate Change

According to Gilder, a 2004 article in the International Journal of Climatology says that all three of the major East African glaciers have seen significant retreat since the late 1800s, which is long before there was much CO2 around.

FORBES: Magazine Article

The glaciers of the Canadian Arctic Archipelago will undergo a dramatic retreat this century if warming projections hold true.

BBC: Canadian glaciers face 'big losses'

Glacier retreat is the prevalent pattern of the Andes, but the contemporary state of alpine glaciers in the Argentine sector of Patagonia seems to be relatively more favourable.

UNESCO: Dublin Core