Throughout Earth’s history, there is evidence of large carbon dioxide releases, greenhouse conditions, ocean acidification, and major changes in marine life. About 120 million years ago (mya), during the early part of the Cretaceous period, a series of massive volcanic eruptions pumped huge amounts of carbon dioxide into Earth's atmosphere. During the Aptian Oceanic Anoxic Event, atmospheric CO2 content rose to about twice today's level. Eventually, the oceans absorbed much of that CO2, which significantly increased the water's acidity. The change reduced the amount of calcium carbonate (CaCO3) in the water, making it difficult for creatures such as some kinds of plankton to form shells. But the plankton did not die out. In fact, the geological record indicates that ocean biota can adapt to CO2 concentrations as high as 2000 to 3000 ppm—five to eight times current levels.
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.
Large portions of the globe rely on the seasonal monsoon for water. Across much of Asia, agriculture depends on the coming of the monsoon rains. One scare tactic employed by global warming extremists is to claim that human caused climate change will keep the monsoon from coming, causing drought, failed crops and famine. In truth, science does not fully understand the complex interactions of ocean, atmosphere, and land that influence the monsoon, or how it impacts climate in other parts of the world. Now, a new Monsoon Asia Drought Atlas (MADA) provides reconstructions of summer moisture for the region going back to 1300 AD. It documents a long sequence of droughts so persistent that scientists call them “megadroughts.” These megadrought events, the worst of which may have toppled ancient kingdoms, show that unreliable monsoon seasons have afflicted mankind throughout history—long before the clamor over climate change arose.
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.
It has come to light that a number of climate scientists have been less than truthful with regard to climate data. As shocking and embarrassing as this has been to the scientific community, it serves only to emphasize the huge blind spot that scientists have for their computer models. It is a career ending offense to knowingly falsify data, yet the entire climate science community engages in even worse deception without a second thought. This is because lies are generated for them wholesale by their faithful yet duplicitous servants: computer climate models.
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 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.
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.
In an essay adapted from his 2009 AAAS Annual Meeting keynote address, James J. McCarthy has produced a fairly concise statement of the anthropogenic global warming believer's world view. After a self-serving review of climate science history, McCarthy trots out the usual litany of climate change troubles: increased cyclones, rain and floods, rising sea levels and, of course, those pesky tipping points. The tone of the article is set early on, when research is cited stating that mankind's impact on Earth is “sufficiently profound to declare that we have transitioned from the Holocene era of Earth history to the Anthropocene.”
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.
Despite recent attempts to revive the discredited “hockey stick” temperature graph, invented by Michael Mann and promulgated by the IPCC, new research on tropical glaciers has once again shown that supposed temperature history to be bogus. While the role of the tropics in climate change remains an open debate in climatology circles, new data suggests linkages between the tropics and the North Atlantic region. In particular, prominent glacial events and associated climatic shifts in the outer tropics during the early Holocene and late in the “Little Ice Age” period indicate that the LIA was indeed a global event.
Using satellite infrared spectroscopy to provide an almost global perspective on the near-surface distribution of water vapor, a new report in Science has identified more water vapor inaccuracies in current general circulation models (GCM), the computer programs used by climate scientists to predict future climate trends. The researchers uncovered anomalies in the Hadley circulation and its misrepresentation in GCM. Looks like climate theory and the IPCC's error ridden models are in for another round of corrections.
Chad, located along the southern edge of the Sahara Desert, is the dustiest place on Earth. Recognizing that aerosols plays a vital role in climate and biophysical feedback in Earth's environmental system, climate researchers are turning to dust as a major driver of climate change. A new article, to be published in PNAS, identifies the Bodélé Depression in Chad as the producer of about half the mineral aerosols emitted from the Sahara. According to Richard Washington et al. dust could be a “tipping element” where “small features of the atmospheric circulation, such as the Bodélé Low-Level Jet, could profoundly alter the behavior of this feature.” With the impact of CO2 diminished due to a cooling climate climate, researchers are searching for new hazards: Is African dust the new carbon dioxide?
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.