Environment

100-year-old expedition logbooks reveal Antarctic sea ice patterns

100-year-old expedition logboo...
Researchers have used the ship logbooks of early 20th century Antarctic explorers, such as Erich von Drygalski's ship the Gauss, to compare sea ice coverage then to now, and found it's largely the same
Researchers have used the ship logbooks of early 20th century Antarctic explorers, such as Erich von Drygalski's ship the Gauss, to compare sea ice coverage then to now, and found it's largely the same
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Researchers have used the ship logbooks of early 20th century Antarctic explorers, such as Erich von Drygalski's ship the Gauss, to compare sea ice coverage then to now, and found it's largely the same
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Researchers have used the ship logbooks of early 20th century Antarctic explorers, such as Erich von Drygalski's ship the Gauss, to compare sea ice coverage then to now, and found it's largely the same

In the early years of the 20th century, several teams of explorers were racing to reach a new frontier: the South Pole. During what's known as the Heroic Age of Antarctic Exploration, many explorers perished and the expeditions were fraught with failure, but their efforts were not in vain. Now, over a century later, their logbooks and journals have helped piece together a new discovery: Antarctic sea ice coverage may not be on a steady downward trend, but fluctuating over cycles lasting decades.

Much of the bad news concerning melting ice is centered around the Arctic region, which is taking a solid beating. At the other end of the world, Antarctic ice shelves are also shrinking by as much as 159 billion tonnes each year, but a new study from the University of Reading suggests this may be part of a longer-term cycle.

Using logbooks from early 20th century explorers, like Robert F. Scott and Sir Ernest Shackleton, the Reading research compared where the edges of the ice were observed then, to where they are now, and found that sea ice levels in the Antarctic summer has only dropped by around 14 percent.

"The missions of Scott and Shackleton are remembered in history as heroic failures, yet the data collected by these and other explorers could profoundly change the way we view the ebb and flow of Antarctic sea ice," says Jonathan Day, lead researcher on the study. "We know that sea ice in the Antarctic has increased slightly over the past 30 years, since satellite observations began. Scientists have been grappling to understand this trend in the context of global warming, but these new findings suggest it may not be anything new."

With the exception of the Weddell Sea, which has declined significantly, the team estimates that in the early 1900s Antarctic ice spanned between 5.3 and 7.4 million km2 (2 and 2.9 million mi2) – figures comparable to today's levels. That means ice coverage may have increased from then up to a peak level during the 1950s, before declining once again to our current figures.

"If ice levels were as low a century ago as estimated in this research, then a similar increase may have occurred between then and the middle of the century, when previous studies suggest ice levels were far higher," says Day.

The study is the first to examine what southern sea ice levels were like before the 1930s, suggesting that Antarctica is much less sensitive to the effects of climate change that are ravaging the Arctic. Instead, the South Pole may undergo regular fluctuations between high and low ice cover, on a scale of decades. Studying more texts from explorers of that time may help paint a clearer picture of these long-term trends.

"The Southern Ocean is largely a 'black hole' as far as historical climate change data is concerned, but future activities planned to recover data from naval and whaling ships will help us to understand past climate variations and what to expect in the future," says Day.

The research was published in the journal The Cryosphere.

Dr. Jonny Day from the University of reading discusses the findings in the following video.

Heroic explorers help make Antarctic sea ice discovery - 100 years on

Source: University of Reading

9 comments
witipete
This is such a problem for proponents of so called global warming. Also interesting to note that global average temperatures in the early 1900's were the same as they are today.
Wolf0579
This is just part of the global warming hoax! j/k
Rann Xeroxx
Sea rise has been accelerating since recordings were started long before AGW were to have started. And in fact recently sea rise has deaccelerated. There is nothing unusual about current warming, we are still coming out of the little ice age... https://iceagenow.info/wp-content/uploads/2011/06/Easterbrook-Natural_global_warming.jpg
ljaques
The article shows that the ice ebbs and flows. The video tries to get people to believe that it's only "less sensitive" to what he surely "knows" is AGWK. I'm glad to see more truth coming out, though Alarmists (like Day) will marginalize or simply refute it. NOW who's the denier? <giggle> But what neither mentions is that on some portions of Antarctica, the ice is thicker now than it had been, showing that while some shrinkage of ice shelf occurs here, it grows over there, on the other side of the continent. There -is- no net loss. I first caught onto the Alarmist bullpuckey after reading Michael Crichton's book, State of Fear.
Robert in Vancouver
This article suggests that the science isn't settled. Throw these deniers in jail and skin them alive. When Al Gore says the science is settled further research is banned and critical thinking is not allowed. The Church of Man-made Global Warming has the final word.
Breaks
Again - cue the clueless brigade and their misunderstanding of how science works. Briefly, no one calls it global warning anymore as some with limitations tended to look out the window at the weather and see no change or even colder weather. Climate change affects weather patterns so as some places heat up it can lead to cooling elsewhere, such as what will happen if the gulf stream gets cooled by the melting iced water coming from the arctic. The water will be cooler, there will be less evaporation leading to completely different weather cycles ie colder in Europe. Its like a fan forced oven versus a standard oven, they bake differently due to the the dispersion of heat. I do feel bad for those who would choose to live in delusion rather than face the perceived embarrassment of admitting ignorance. Try using the internet for scientific education rather than propping up a personal conspiracy theory.
WarrenHarding
Oh no, here come the climate change deniers (predictably).
habakak
Climate change is a non-issue. Just my opinion. Just like all the other issues we have faced in the prior century and before, this will be resolved. I believe AGW is true and happening. However it is a short term problem that is already being solved. Now to the issue I have. How can we trust our estimation of ice coverage and climate thousands and hundreds of thousands of years ago, yet we now learn from some documents how wrong we were about ice coverage and climate just the past 100 years?????? Just like the Antarctic might now be at a lower total ice coverage percentage like it was 100 years ago (and it was higher 50 years ago, leading us to think it's a runaway melting problem), couldn't the Arctic be going through the same? A temporary 200 year melt down maybe? Or 300 year half-cycle? Either way, just like humans have always panicked about the coming apocalypse, this will also turn out to be nothing in half a century or less from now.
JoelHuet
One thing is for sure: the deniers are not getting smarter. One says it's nothing unusual, we're coming out of the Little Ice Age. So climate must be working a bit like a spring. Except neither he nor any of his denier ilk can tell us what that mysterious force is _ one that can't be measured nor observed _ that is causing the climate to spring back. Another one takes a graph of the temperature data, turns it 45 degrees and voila! It's flat. Now the global average temperature 100 years ago is the same as today. And to top it off, there's one that boast about learning climate science by reading Michael Crichton. It's hard to know whether to laugh or cry.