Despite hype by environmentalists and many media outlets, the slow collapse of major glaciers in western Antarctica is nothing new, according to scientists. The warming and cooling in the South Pole is well in line with historical trends dating back thousands of years.
The British Antarctic Survey (BAS) has released two major studies in the last year that have shed light on western Antarctic collapsing glaciers — both of which show that the thinning sea ice in the western south pole is nothing new.
A BAS study released in February found that 8,000 years ago Antarctica’s Pine Island glacier thinned just as fast as it has in recent decades. This happened thousands of years before the Industrial Revolution, which scientists and environmentalists blame for releasing massive amounts of carbon dioxide emissions that have warmed the atmosphere.
The point of the BAS study was to see how a thinning Pine Island glacier affected sea levels thousands of years ago. Scientists say Pine Island is currently going through “ocean-driven” melting — as more warm ocean water is getting under the ice shelf.
“Our geological data show us the history of Pine Island Glacier in greater detail than ever before,” the study’s lead author Joanne Johnson of BAS said in a statement. “The fact that it thinned so rapidly in the past demonstrates how sensitive it is to environmental change; small changes can produce dramatic and long-lasting results.”
“Based on what we know, we can expect the rapid ice loss to continue for a long time yet, especially if ocean-driven melting of the ice shelf in front of Pine Island Glacier continues at current rates,” Johnson said.
Not only did Pine Island glacier experience similar melting to today, it also was able to reverse the melting naturally.
Another study from BAS released last year found that the current melt in the western Antarctic is within the “natural range of climate variability” of the last 300 years.
“The record shows that this region has warmed since the late 1950s, at a similar magnitude to that observed in the Antarctic Peninsula and central West Antarctica,” said a BAS study published in the journal Geophysical Research Letters last year, “however, this warming trend is not unique.”
“More dramatic isotopic warming (and cooling) trends occurred in the mid-19th and 18th centuries, suggesting that at present the effect of anthropogenic climate drivers at this location has not exceeded the natural range of climate variability in the context of the past ~300 years,” the study said.