Much concern has been raised by climate scientists regarding ice loss from the world's two remaining continental ice sheets. Rapid loss of ice-mass from the glaciers of Greenland and Antarctica are cited as proof positive of global warming's onslaught. The latest measurements involve the use of satellite gravimetry, estimating the mass of terrain beneath by detecting slight changes in gravity as a satellite passes overhead. But gravity measurements of ice-mass loss are complicated by glacial isostatic adjustments—compensation for the rise or fall of the underlying crustal material. A new article in Nature Geoscience describes an innovative approach employed to derive ice-mass changes from GRACE data. The report suggests significantly smaller overall ice-mass losses than previous estimates.
Like an overly familiar maniac from a series of Hollywood slasher movies, CO2 has lost most of its ability to scare the public. Carbon dioxide's diminishing fright mojo has sent climate change alarmists—and those in the media who lend them mindless support in trade for salacious headlines—casting about for a next gas molecule to scare the public with. A few trial balloons have been floated for oxides of nitrogen (NOx) but the rising star in the global warming shop of horrors is methane (CH4). Aside from having a familial relation ship with CO2 based on carbon, CH4 is a known greenhouse gas and is produced almost everywhere on Earth by decaying organic matter. Most recently, there were panicked warnings that Arctic seabed methane stores were being destabilized. The hype over methane has gotten so out of hand that a news focus article in Science (which is not a hot bed of climate change skepticism) has publicly stated the situation is being exaggerated.
Around 3 million years ago, Earth's climate started growing colder. Glaciers began forming in high northern latitudes, while surface waters cooled in parts of the equatorial Atlantic and Pacific Oceans. At the same time, climate sensitivity to variation in the tilt of Earth's axis—called obliquity—increased substantially. Since that time, changes in sunlight associated with obliquity have caused variation in global ice volume and equatorial sea surface temperatures (SST). Inexplicably, variations at the equator occurred a few thousand years before those in high latitudes and thus could not have been a direct consequence of the waxing and waning of glaciers. Two new papers in the June 18, 2010, issue of Science attempt to explain the true causes of climate change.
Earth's climate history includes numerous incidents of rapid warming and cooling. While Pleistocene ice-age glacial terminations are arguably the most dramatic recent examples of sudden climate change, during the last glacial period the climate of the Northern Hemisphere experienced several other significant episodes when the climate rapidly warmed. Scientists call these episodes Dansgaard-Oeschger (DO) events after the Danish and Swiss researchers who documented them using ice-core studies. These rapid oscillations are marked by rapid warming, followed by slower cooling. The most prominent coolings are associated with massive iceberg discharge into the North Atlantic Ocean known as Heinrich events (HE). The melting icebergs add large volumes of cold fresh water to the ocean, disrupting circulation patterns and causing further climate changes. Scientists look to past events like these to help us understand how Earth's climate system functions—what causes our planet to cool or suddenly warm. Recently, new data on past climate changes have led one commentator to predict the end of winter skiing in the American Southwest.
Forests and their soils are one of our planet's major sinks of biologically active carbon and contain the majority of Earth’s terrestrial carbon stock. Some climate change alarmists have said that the world's forest are in danger from the effects of climate change. Recent studies have shown increases in plant growth across many forest types. Now, a new paper in the Proceedings of the National Academy of Sciences reports that the increase in forest biomass is due to rising CO2 levels and warmer weather—in other words, trees love global warming whether human caused or natural.
With all the predictions of short term climate catastrophes proffered by global warming alarmists it is hard to look forward to a future time on Earth. What does the future hold a thousand, ten thousand, a million years from now? Science has some predictions about that as well, though the news media have not picked up on them. What environmental changes await us on the long road ahead?
One well accepted definition of the “Three Pillars of Science” lists the three as theory, experimentation and computation. For climate science this translates into climate theory, gathering climate data, and climate modeling. The three pillars are due an update in this post Copenhagen, post Climategate world. After reviewing the past year's crop of discoveries and disclosures, it seems that all three pillars are still wobbly at best—even without questionable conduct on the part of warm-mongering researchers.
Recent claims by climate change alarmists have raised the possibility that terrestrial ecosystems and particularly the oceans have started loosing part of their ability to absorb a large proportion of man-made CO2 emissions. This is an important claim, because currently only about 40% of anthropogenic emissions stay in the atmosphere, the rest is sequestered by a number of processes on land and sea. The warning that the oceans have reached their fill and their capacity to remove atmospheric CO2 is accompanied by the prediction that this will cause greenhouse warming to accelerate in the future. A new study re-examines the available atmospheric CO2 and emissions data and concludes that the portion of CO2 absorbed by the oceans has remained constant since 1850.
In the run up to Copenhagen, global warming alarmists are spreading the word that climate change is progressing even faster than the IPCC has projected. But contradictory data from skeptics and open minded scientists continues to indicate that global warming has gone on hiatus and may not return for decades. This has sparked a noticeable drop in public concern over climate change and has led some climate change true believers to bemoan increasing public “Climate Fatigue.”
According to a flurry of recent reports by the BBC and other mass media, the glaciers in the Himalayan mountains are melting at a furious pace. Of course this is taken as proof that climate change is still taking place at an ever accelerating rate, despite the fact the global temperatures have remained flat for the past decade. What, then, explains the rapidly retreating Himalayan glaciers? Nothing, because the glaciers are not shrinking. A new report by a senior Indian glaciologist states that the glaciers remain frozen and quite intact, thank you.
A new study has confirmed the astronomical theory of the ice ages, but with a new twist: The shutoff of the meridional ocean circulation, or MOC, and an associated southward shift of tropical monsoon rain belts seems to play an integral role in the melting of glacial period ice sheets. These changes cause warming of the Southern Hemisphere and a rise in atmospheric CO2 levels, which in turn provides a positive feedback loop that helps drive glacial termination. This is why, every 100,000 years or so, the great Northern Hemisphere ice sheets collapse and glacial conditions give way to a warm interglacial period, such as the Holocene warming humanity is currently enjoying. This, however, does not support recent claims that global warming is causing the Southeast Asian monsoon to fail.
The supporters of anthropogenic global warming (AGW) claim that they have science on their side. Time and again we are told that the debate is over, the science is settled and consensus among the world's scientists reached. If that is true, why are so many scientists coming forward to oppose and denounce the climate alarmist's theory? To understand the true nature of the climate change debate it is necessary to understand what a scientific theory is and how to judge a theory's validity.
Two of the terms bandied about by global warming alarmists are “unprecedented” and “irreversible.” It is troubling that scientists, who should know better, persist in using these terms even though the history of our planet clearly shows that neither term is accurate. Proof of this inaccuracy is obvious if we look back over the history of Earth—the Phanerozoic Eon in particular—taking the “Grand View” of historical climate change.
Increased insolation 20,000 years ago caused deglaciation in the Northern Hemisphere, according to a new report in the August 7, 2009, edition of Science. Further more, it was the onset of deglaciation of the West Antarctic Ice Sheet, which occurred between 14 - 15 thousand years ago, that was the source of sea-level rise at the beginning of the Holocene warming. Such events are often associated with rising CO2 levels by climate catastrophists but the evidence says otherwise.
Two articles in the July 17 edition of Science describe efforts to model Earth's rapidly changing climate at the end of the last glacial period, between 21 and 11 thousand years years ago (ka). After a year and a half of number crunching on Oak Ridge National Laboratory's Jaguar supercomputer, the first results indicate that climate experienced cooling 17 ka, during the Heinrich Event 1 (H1), followed by an abrupt warming at the onset of the Bølling-Allerød Warming 14.5 ka. These abrupt climate changes were accompanied by large changes in the “ocean conveyor belt”: the Atlantic meridional overturning circulation (AMOC). The results suggest that this transition can be viewed simply as the North Atlantic climate response to rapidly changing glacial meltwater flow. The findings call for a paradigm shift in our understanding of abrupt climate change and weakens the threat of “irreversible tipping points” so popular with climate change extremists.