After nearly 50 years of acceptance, the theory that a great ocean “conveyor belt” continuously circulates water around the globe in an orderly fashion has been dismissed by a leading oceanographer. According to a review article in the journal Science, a number of studies conducted over the past few years have challenged this paradigm. Oceanographers have discovered the vital role of ocean eddy currents and the wind in establishing the structure and variability of the ocean’s overturning. In light of these new discoveries, the demise of the conveyor belt model has been become the new majority opinion among the world's oceanographers. According to M. Susan Lozier, of Duke University, “the conveyor-belt model no longer serves the community well.”
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.
Often a target for environmentalists and global warming alarmists alike, intensive modern agriculture has been demonized as the cause of many types of pollution, including those dreaded greenhouse gases. A study, soon to appear in the Proceedings of the National Academy of Sciences (PNAS), reveals that highly productive modern agriculture actually reduces net greenhouse gas emissions when compared with using croplands less intensively. Furthermore, expansion of agriculture, needed to feed mankind's ever growing numbers, can help reduce future increases in CO2 emissions. Looks like the doomsayers got it backwards again, more intensive agricultural is a good thing for the environment. In fact, agriculture reduced total human carbon emissions from 1850 to 2005 by 34%.
There have been arguments made for increased plant growth due to rising atmospheric CO2 levels, while others have argued against it. Now it seems that green plants and ocean algae are not the only forms of life involved. Opportunistic microorganisms are stepping in to sop up excess carbon. A new report in the Proceedings of the National Academy of Sciences (PNAS) has identified soil fungi as a major player in accelerating CO2 absorption. Arbuscular mycorrhizal fungi (AMF) have been identified as an intermediary between plants and other bacterial and fungal populations, acting as a buffer for other soil-borne communities. Existing organisms are not just working harder, new communities are developing to take advantage of increased CO2 levels, demonstrating that nature possesses self-regulation mechanisms science did not anticipate and has yet to discover.
If a letter appearing in the May 7, 2010, issue of Science is any indication, it looks like climate science traditionalists are trying to stage a comeback. The article by P. H. Gleick and a cast of hundreds, entitled “Climate Change and the Integrity of Science,” states that “we are deeply disturbed by the recent escalation of political assaults on scientists in general and on climate scientists in particular.” Decrying the attacks on climate scientists by “deniers,” the letter reiterates the signatories' support for dogmatic climate change theory. While admitting that the IPCC “quite unexpectedly and normally, made some mistakes,” they call for an end to “McCarthy-like threats” against themselves and their colleagues. Painting themselves as victims, they have gone on the offensive—like the evil Empire of Star Wars fame, climate science is striking back.
Since the Mid-Brunhes Event, around 430,000 years ago, interglacial periods have grown warmer and their CO2 levels higher. Research confirms that Croll and Milankovitch were right: Earth's orbital cycles seem to be the cause of these documented cases of true global warming, with CO2 playing a supporting role, not the lead. Many of the catastrophic events warned of by climate change alarmists turn out to be well within the range of natural variation. Moreover, new findings indicate that the effects of the cycle induced changes, through their impact on the environment in the Southern Hemisphere, are not correctly accounted for in the IPCC models.
Asking the somewhat obvious question, “are cold winters in Europe associated with low solar activity?” a group of scientists have announced that the answer is yes. While this may seem unsurprising, the finding is another indication that Earth's climate is not simply driven by greenhouse gas emissions. Even so, some scientists are only grudgingly accepting the finding, cautioning that this only applies in the central UK and refusing to admit that the Sun could affect global mean temperatures as well. Still, the researchers found that average solar activity has declined rapidly since 1985 and cosmogenic isotopes suggest a possible return to Maunder minimum conditions within the next 50 years. This could be a sign that climate science is starting to recover from its CO2 fixation.
The current hot buzzword in Information Technology (IT) circles is “cloud computing,” the concept of a shared grid of computer resources, made available to a wide range of consumers in an on-demand, self-service and pay-as-you-go fashion. Even those not immersed in the arcane details of IT are aware of the latest must have techno-doodad from Apple Computer—the iPad. Proving that they can find a dark cloud to go with any silver lining, the perennial eco-pessimists from Greenpeace have declared that the combination of iPads and cloud computing are going to greatly accelerate mankind's march to a planet frying future.
Although the story of the “Asteroid that killed the Dinosaurs” has become common knowledge for most people, there are still those scientists who back alternative causes of the end Cretaceous extinction even. Volcanoes, multiple meteor strikes and even widespread forest fires have been suggested as the cause of the dinosaurs' demise. The extinction event 65.5 million years ago did coincide with a large asteroid impact at Chicxulub, Mexico, and occurred within the time of Deccan flood basalt volcanism in India. A new review article by 41 scientists in the March 5 edition of Science runs down the list of what science thinks it knows about the extinction that set the stage for the age of mammals.
Recently, a number of papers have surfaced that use advanced statistical methods to analyze climate data. The techniques involved have been developed not by climate scientists but by economists and social scientists. These new tools belong to the field of econometrics. The use of statistical break tests and polynomial cointegration to analyze the relationships between time series data for greenhouse gas concentrations, insolation, aerosol levels and temperature have shown that these data are non-stationary. The implication of these findings is that much of the statistical analysis applied by climate scientists is flawed and potentially misleading. So strong is the statistical evidence that a couple of economists are claiming to have refuted the theory of anthropogenic global warming. This, on top of everything else that has recently transpired, may indicate that a climate change paradigm shift is imminent.
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.
The golden toad of Costa Rica was declared extinct in 1994, five years after it was last sighted in the wild. The unfortunate toad's was the first extinction to be blamed on anthropogenic global warming and it has often been cited as an example of things to come if mankind doesn't change its CO2 spewing ways. But humanity's conviction of toadacide was premature and based on circumstantial evidence. After years of study scientists have a new finding: humans were not at fault after all.
There have been a rash of bogus reports in the news media about rapidly rising sea-levels supposedly caused by global warming. Sea-levels are notoriously hard to measure on a global basis since land also rises and sinks due to tectonic activity. With historical records mostly unreliable how can we tell if current conditions are normal for Earth 14,000 years after a deglaciation? A new report, based on calcium growths in caves on the Mediterranean island of Mallorca, says that sea levels around 81,000 years ago were higher than today. Higher sea-levels imply less glacial ice and warmer temperatures than today as well. Even more interesting is that this occurred during a warm period called marine isotope stage (MIS) 5a, which was more than 30,000 years after the Eemian interglacial ended and glaciation had resumed. This could mean that current theories about how ice age glacial periods start are wrong.
With CO2 driven global warming becoming more discredited by new scientific evidence every day, the world's meddling climate regulators are casting about for a new gas to demonize. Last year the US Environmental Protection Agency was reportedly thinking of even classifying water vapor as a pollutant, due to its central role in global warming. Because water vapor is the dominant greenhouse gas in the atmosphere, accounting for the majority of the Earth's natural greenhouse effect, water vapor emissions during human activities—such as the processing and burning of fossil fuels—are again coming under increasing scrutiny by government regulators.
The debate over anthropogenic global warming—a theory propounded by the UN IPCC—is often portrayed as an argument between deniers and true believers. The deniers supposedly claim that there is no global warming, man made or otherwise, and that the whole theory is a plot by left-wing agitators and closet socialists bent on world domination. The true believers, conversely, accept every claim of pending future disaster uttered by scientists and activists alike. As with most controversies both extreme positions are wrong and the truth lies somewhere in-between. As a scientist, I have studied the evidence and find the case for imminent, dangerous, human caused global warming unconvincing—here is why I am an AGW skeptic.