Tag: Antarctica

Global Science Report: Sea Ice Expansion in the Southern Hemisphere Is Real and Driven by Falling Temperatures

While there’s been thousands of legacy media stories about the very real decline in summer sea-ice extent in the Arctic Ocean, we can’t find one about the statistically significant increase in Antarctic sea ice that has been observed at the same time.

Also, comparisons between forecast temperature trends down there and what’s been observed are also very few and far between. Here’s one published in 2015:

Observed (blue) and model-forecast (red) Antarctic sea-ice extent published by Shu et al. (2015) shows a large and growing discrepancy, but for unknown reasons, their illustration ends in 2005.

Observed (blue) and model-forecast (red) Antarctic sea-ice extent published by Shu et al. (2015) shows a large and growing discrepancy, but for unknown reasons, their illustration ends in 2005.

For those who utilize and trust in the scientific method, forming policy (especially multi-trillion dollar policies!) on the basis of what could or might happen in the future seems imprudent. Sound policy, in contrast, is best formulated when it is based upon repeated and verifiable observations that are consistent with the projections of climate models. As shown above, this does not appear to be the case with the vast ice field that surrounds Antarctica.

According to the most recent report by the Intergovernmental Panel on Climate Change (IPCC), CO2-induced global warming will result in a considerable reduction in sea ice extent in the Southern Hemisphere. Specifically, the report predicts a multi-model average decrease of between 16 and 67 percent in the summer and 8 to 30 percent in the winter by the end of the century (IPCC, 2013). Given the fact that atmospheric CO2 concentrations have increased by 20 percent over the past four decades, evidence of sea ice decline should be evident in the observational data if such model predictions are correct. But are they?

Thanks to a recent paper in the Journal of Climate by Josefino Comiso and colleagues, we now know what’s driving the increase in sea-ice down there. It’s—wait for it—cooling temperatures over the ocean surrounding Antarctica.

Global Science Report: Antarctic Updates

The northern end of the Antarctic Peninsula is Warming Fast
BBC, August 23, 2012

No, it’s not. When BBC reported this, the Northern Peninsula hadn’t on average warmed a lick in thirty years.

In the 1990s and early part of this century, news reports about the dramatic warming of the northernmost Antarctic Peninsula—the tip of the 800-mile dagger pointed at the heart of Tierra del Fuego—were a common staple. And, while scientists wouldn’t write this in the literature, they were happy to blame it on dreaded carbon dioxide on television, as paleoclimatologist Robert Mulvaney did in the 2012 BBC feature.

The story has become increasingly curious. Marc Oliva of the University of Lisbon recently examined the high quality weather stations over the northern peninsula and the nearby South Shetland Islands. There is a decent warming trend, averaging around 1.5⁰C, from the beginning of the data in 1957 (the year when Antarctica was instrumented as a part of the International Geophysical Year) to the early 1980s, or about a quarter-century. That’s a warming, if it continued (and surely it would!), of 6⁰C per century. The warming that gets huge attention is actually only from a single station, Faraday (now renamed Vernadsky), which warmed roughly 2.5⁰C during the same period. If that continued (and surely it would!), that’s 10⁰C/century!

Oliva et al. wrote that the “Faraday/Vernadsky warming trend is an extreme case, circa twice those of the long-term records from other parts of the AP.” The variability in the Faraday/Vernadsky record is also huge—around three times as much as other stations in the area, probably because it is often at the edge of the sea-ice.

Two Millennia of Snowfall Accumulation in Antarctica

Providing the rationale for their work, Roberts et al. (2015) write that “the short and sparse instrumental record in the high latitudes of the Southern Hemisphere means investigating long-term precipitation variability in this region is difficult without access to appropriate proxy records.” It was therefore the objective of this team of nine researchers to extend the duration of the Law Dome, East Antarctica, snowfall accumulation record back in time an additional 750 years so that it would cover over two millennia.

The resultant 2035 year-long proxy (22 BC to 2012 AD) is presented in the figure below. As reported by the authors, the average long-term snow accumulation rate was calculated as 0.686 m yr-1 (27 inches) ice equivalent, which rate they say “is in agreement with previous estimates, and further supports the notion that there is no long-term trend in snow accumulation rates, or that any trend is constant and linear over the [2035-year] period of measurement.”

If this number seems low for such an icy continent, the fact is that most high-latitude locations in both hemispheres would qualify as deserts based upon annual precipitation. In many places, it is literally “too cold to snow” as the frigid air can hold only tiny amounts of moisture.

There were several decadal-scale oscillations in the record, described by the authors as “common,” with “74 events (33 positive and 41 negative) of at least a 10-year duration in the record.”  The three longest periods of above average integrated snowfall occurred over the intervals 380-442, 727-783, and 1970-2009, while the three longest periods of below average integrated snowfall occurred during 663-704, 933-975, and 1429-1468.

You Ought to Have a Look: Antarctic Ice, Summer Thunderstorms, and Cold Winters

You Ought to Have a Look is a feature from the Center for the Study of Science posted by Patrick J. Michaels and Paul C. (“Chip”) Knappenberger.  While this section will feature all of the areas of interest that we are emphasizing, the prominence of the climate issue is driving a tremendous amount of web traffic.  Here we post a few of the best in recent days, along with our color commentary.

In this week’s You Ought to Have a Look, we’re going to catch up on some new climate science that hasn’t gotten the deserved attention—for reasons soon to be obvious.

First up is a new study comparing climate model projections with observed changes in the sea ice extent around Antarctica.

While everyone seems to talk about the decline in the sea ice in the Northern Hemisphere, considerably less discussion focuses on the increase in sea ice in the Southern Hemisphere. If it is mentioned at all, it is usually quickly followed by something like “but this doesn’t disprove global warming, it is consistent with it.”

But, even the folks delivering these lines probably realize that the latter bit is a stretch.

In fact, the IPCC and others have been trying downplay this inconvenient truth ever since folks first started to note the increase. And the excuses are getting more involved.

A new study pretty much exposes the emperor.

Some Perspective on the Headlining Antarctic Ice Loss Trends

The mainstream media has lit up the past few days with headlines of “alarming” news coming out of Antarctica highlighting new research on a more rapid than expected loss of ice from glaciers there.

But, as typical with blame-it-on-humans climate change stories, the coverage lacks detail, depth, and implication as well as being curiously timed.

We explain.

The research, by a team led by University of Cal-Irvine doctoral candidate Tyler Sutterley, first appeared online at the journal Geophysical Research Letters on November 15th, about two weeks before Thanksgiving. So why is it making headlines now? Probably because the National Aeronautics and Space Administration issued a press release on the new paper on December 2nd. Why wait so long? Because on December 1st, the United Nations kicked off its annual climate confab and the Obama administration is keen on orchestrating its release of scary-sounding climate stories so as to attempt to generate support for its executively commanded (i.e., avoiding Congress) carbon dioxide reduction initiatives that will be on display there. This also explains the recent National Oceanic and Atmospheric Administration speculation that 2014 is going to be the “warmest year on record”—another headline grabber—two months before all the data will be collected and analyzed.

This is all predictable—and will essentially be unsuccessful.

Missing from the hype are the broader facts.

The new Sutterley research finds that glaciers in the Amundsen Sea Embayment region along the coast of West Antarctica are speeding up and losing ice. This is potentially important because the ice loss contributes to global sea level rise. The press coverage is aimed to make this sound alarming—“This West Antarctic region sheds a Mount Everest-sized amount of ice every two years, study says” screamed the Washington Post.

Wow! That sounds like a lot. Turns out, it isn’t.