The vast majority of the world's glaciers are retreating as the planet gets warmer. But a few, including ones south of the equator, in South America and New Zealand, are inching forward.
A new study in the journal Science puts this enigma in perspective; for the last 7,000 years New Zealand's largest glaciers have often moved out of step with glaciers in the northern hemisphere, pointing to strong regional variations in climate.
Conventional wisdom holds that climate during the era of human civilization has been relatively stable, but the new study is the latest to challenge this view, by showing that New Zealand's glaciers have gone through rapid periods of growth and decline during the current interglacial period known as the Holocene.
"New Zealand's mountain glaciers have fluctuated frequently over the last 7,000 years and glacial advances have become slightly smaller through time," said lead author Joerg Schaefer, a geochemist at Columbia ...