Nigard was a farm situated in a valley in west Norway. Farther up the valley there was a lake, and farther still a relatively small glacier, a side arm of the Jostedal Glacier high in the mountains to the east of the farm.
This is how things were during the Medieval Warm Period.
But then things changed. With the onset of the Little Ice Age, the Jostedal Glacier started to put on weight. Its side arms started to move out to the sides.
What had been a relatively small glacier, far away from Nigard, grew in size and extent. It pushed down to the lake. It crossed the lake, It pushed on beyond the lake. By 1650, some 400 years after the onset of the Little Ice Age, it had reached Nigard.
The expansion, which had been slow and gradual to start with, had by then become alarmingly rapid.
By the time the expansion finally stopped a hundred years later, Nigard and all its land was gone. It had been completely consumed by ice.
Historic extent of the Nigard Glacier
Illustrasjon: Bjørn Vold
By 1850, a mere 100 years after the Nigard glacier reached its maximum extent, half of it, by volume, had melted away. By 1930, its volume was cut in half again. Fast forward another 90 years, and we’re back to where we were right after the onset of the Little Ice Age.
What’s interesting to note from a climate perspective is that the greatest reduction of ice, by volume, happened from 1750 to 1850. What is happening today, where the remaining bits of the Jostedal side arms are melting away, is in no way as dramatic as what happened during the first hundred years of glacial retreat.
Furthermore, it is impossible to read into this any correlation to human activity. The Nigard glacier came and went, long before the CO2 content in our atmosphere made its jump from 0.03% to the current level of about 0.04%.
The exponential increase in CO2 content happened after 1930, when the Nigard Glacier was already less than a quarter of what it once had been.