The decline of glacier ice volumes in New Zealand
New Zealand glaciers have shrunk by almost 20 cubic kilometres in the last 36 years.
According to the Ministry for the Environment, glacier ice volumes in 1978 were above 50 cubic km.
In 2014, it dropped to slightly more than 35 cubic km.
University of Otago department of geography lecturer in hydrology Sarah Mager said last year that ice loss observed at the famous Tasman Glacier was likely a natural readjustment to climate changes.
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Melting ice had formed a terminal lake.
The glacier was losing more ice volume than was being naturally replaced through snowfall and ice accumulation, Mager said.
The terminal lake is now 7 kilometres long and deeper than Lake Pukaki due to the glacier's ice loss, and was expected to grow much larger.
Victoria University and Niwa published research in February, that found at least 58 New Zealand glaciers grew bigger between 1983 and 2008.
Franz Josef Glacier grew almost continuously during this time.
Victoria's Antarctic Research Centre associate professor Andrew Mackintosh said they grew due to lower temperatures in New Zealand.
But many of the country's largest glaciers have retreated substantially since 2011 with several on track to disappear entirely.
Both Franz Josef Glacier and Fox Glacier are no longer accessible by foot due to their retreat.
Learn more about the information shown above, and explore more charts, at Figure.NZ's site.