Charts going back to the 1980s show a reduction in summertime sea ice extent in the Arctic. It’s one of the points climate alarmists routinely bring up when they want to emphasize the unprecedented changes the Earth is now supposedly going through. But what was the ice like before the 1980s? Since there weren’t satellites or other observing systems available through history, scientists have to use indirect indicators. And via Kenneth Richard of No Tricks Zone we have learned of a set of new studies, one from Canada’s Beaufort Sea and two from the Barents Sea near Svalbard, which show that current sea ice levels in the Arctic are in fact remarkably high compared to most of the current interglacial period. Indeed in both locations there are indications that, notwithstanding the recent change, current temperatures are lower, and sea ice extent is higher, than at any time since the last glaciation ended 11,000 years ago.
The studies looking at the Barents Sea are available online here and here. The first, by Brice et al., found evidence that today’s sea surface around Svalbard gradually warmed throughout the post-glacial interval, reaching a maximum about 4° C warmer than at present in the Roman era. The region at that time was ice-free nearly all year round. Then cooling set in and has continued ever since, with current conditions as cold and icy as they were back at the tail end of the ice age. The second study, by Allaart et al., finds further that Svalbard glaciers melted back dramatically in the first few millennia of the Holocene interglacial period, reaching several kilometers inland compared to where they are currently. They have since grown and sea ice in the region is at its greatest extent in about 11,000 years.
The Beaufort article is available here and reveals almost exactly the same pattern on the Canadian side of the Arctic. From about 14,000 to 8,000 years ago that part of the Arctic was nearly ice-free all year round, and temperatures were about 4° C warmer. But it has cooled since then and now is 70-100% covered in ice for all but 1-2 months of the year.
We have discussed the challenges of explaining changes in Arctic sea ice previously, when we pointed to evidence that Arctic ice coverage was much lower in the 1800s than it is today, and that climate models have been found to overstate current warming trends. These new studies fit the pattern. Even with CO2 levels much lower, nature itself was perfectly capable of warming the Arctic and melting the ice way back. And even with high modern CO2 levels, the Arctic has become colder and icier than in the past. As we noted before, don’t rush out to buy that Arctic beachfront lot just yet.
