That large changes in solar radiation can affect Earth's climate is widely accepted. However, the hypothesis of solar-induced centennial to decadal climate changes, which suggests feedback mechanisms in the climate system amplifying even small solar variations, has not found acceptance among orthodox climate scientists. The climate change clique would rather place their money on greenhouse gasses—human generated CO2 in particular. It is true that satellite-based measurements of total solar irradiance show that mean variations during solar cycles do not exceed 0.2 W m−2 (~ 0.1% of the Sun's energy output). It has also been noted that relatively large variations of 5–8% in the ultraviolet (UV) frequencies can occur, though how this could change global climate remained a puzzlement—but perhaps no longer. From studying a significant climate shift 2,800 years ago, a group of scientists have concluded that large changes in solar UV radiation can, indeed, affect climate by inducing atmospheric changes.
A new study in the Proceedings of the National Academy of Sciences (Early Edition on-line), is shaking up science's view of polar bear evolution. Previously, it had been suggested that the white bear of the north was a relatively young species that diverged from brown bears during the last glacial period. That glaciation started after the Eemian epoch (~125,000 years ago), peaking around 25,000 years ago. New genetic analysis pushes that estimated divergence back to 4-5 million years ago, though there seems to have been a significant level of interbreeding between the two species over time. Another important finding is that the polar bear population underwent a significant contraction around 500,000 years ago. According to this new information the polar bear has been around for much longer than previously thought, implying that it has survived many interglacial warm periods. In other words, those who think the polar bear cannot survive the shrinking of Arctic ice packs are dead wrong.
Melting glaciers are once again in the news, along with the associated threat of rising sea levels. NASA satellites have reported wide spread melting across Greenland which has the climate change alarmists all atwitter. But the NASA satellites are providing data never before available, so it is hard to say if the summer melting pattern is unusual. Meanwhile, some 80 year old scientific data has revealed that this is not the first time that there has been a period of glacial retreat in Greenland. This formerly lost data shows that many land-terminating glaciers underwent a more rapid retreat in the 1930s than in the 2000s. Even more interesting is that the two periods of retreat were interrupted by a period of widespread advance from 1943 to 1972. Greenland's glaciers seem to be oscillating with a period of around a century.
The last interglacial period (LIG)—the Eemian—is commonly believed by scientists to have been warmer than the current Holocene interglacial. Along with that balmier climate there is evidence that sea levels were significantly higher than today. Previous studies have pegged Eemian sea levels at 4 to 6m higher than today. Recently, a new investigation raises that estimate, reporting that ancient sea levels peaked between 6.6 and 9.4 m (~20 to 30 feet). Modern day accounts of flooding in low lying coastal areas and tropical islands abound, with ominous suggestions of links to global warming. How high the oceans will rise is a topic of debate for IPCC members, the news media and assorted climate alarmists, but they are asking the wrong question. Instead, they should ask why are sea levels so low?
Between 15 and 20 million years (Myr) ago, Earth's climate took a pause during its long slide into the Pleistocene Ice Age for a period of real global warming. During this relatively brief time glaciers around the world retreated and there are indications that, at least around the edges of the continent, there was significant vegetation on Antarctica. Temperatures may have been as high as 11°C higher than today. Scientists say this global warm spell took place under under CO2 levels in the range of 190–850 ppmv, both significantly higher and lower than today's 390 ppmv. It is hoped that studying conditions during the Miocene warming can provide constraints on the fundamental laws governing the climate system. Why? If the Pleistocene Ice Age is truly coming to an end, as some have said, this may be the climate of the future.
After decades of debunking and statements by responsible scientists that climate is not weather and individual anomalies are not an indication of climate change, the government funded IPCC lackeys at the UK's Met Office and America's National Oceanic and Atmospheric Administration have publicly attributed recent bad weather events to man-made climate change. These irresponsible boffins' shrill claims illustrate the desperation in the anthropogenic global warming (AGW) camp in the face of declining public concern over climate change. While admitting that it is impossible to blame a single event on global warming, climate alarmists are claiming attribution is possible as long as it is framed in terms of probability. They have gone from lies, to damn lies and now, finally, to statistics.
In a new study of coral reefs off the Pacific coast of Panama, a team of scientists has discovered something shocking: those seemingly thriving, permanent reefs have undergone widespread devastation in the past. Even more shocking was the realization that, despite this natural destruction of coral reefs, the reefs bounced back—after laying dormant for 2,500 years. We have been told that the oh so sensitive coral reefs of the world are all going to die if the world's temperature rises due to that horrible man-made scourge, global warming. Yet it seems that nature has been happily wiping out and re-establishing reefs across all the oceans of the world since before the rise of human civilization. Once again the warmists' scare tactics founder on the reefs of actual science.
The following is taken from an interesting article about the debate over climate change (a link to the whole article is provided): It is very difficult to understand the climate change denial platform on a purely philosophical and scientific level. Climate change is a rather obvious aspect of the history of the Earth and clearly man interacts with climate in an increasingly dynamic manner. That this is even debated appears on the surface to be not a little ridiculous-somewhere on the level of discussing whether the Earth is round or flat.
The IPCC is working up to releasing pieces of its next climate report, starting in 2013. This has the world's climate scientists scrambling to get their latest work included in that dubious document. Foremost among those struggling for primacy of place are the computer modelers, those who study their own created worlds instead of the natural one around them. This report promises to be more contentious than the last one (AR4) in that the modelers have been racing to incorporate the effects of aerosols, soot and other airborne particulates that had previously been give scant attention. Early results suggest that aerosols have a much greater impact on regional climate than scientists had realized and that aerosols and clouds are providing some big surprises.
Resilient Earth coauthor, Dr. Doug L. Hoffman, has contributed a chapter to a new text book in GALE CENGAGE Learning's Opposing Viewpoints series entitled “Switching to Renewable Energy Is Prohibitively Expensive.” Based on his blog article, “The Cost Of Running The World On Renewable Power,” the published version provides a counterpoint to the views of green advocates also presented in the book. “I am really pleased to get this chance to present an opposing viewpoint to the standard line of green advocacy found in normal school textbooks,” said the author. “Illogical policies can only be countered with reason and, to be able to reason, students need to hear more than one side of an issue.”
A new Current Biology paper proposes that the accumulated output of dinosaur flatulence could have changed the global climate during the age of the dinosaurs. Insert dinosaur fart joke here. No, seriously, this is a real report in an actual scientific journal. It just happens to be on a subject that the news media could not resist blowing out of proportion on their best day. Given that much of the CO2 in Earth's atmosphere was emitted by some form of living creature this is a serious area for study by environmental scientists. So after giving the chattering media magpies some time to calm down, here is a more serious take on this heady topic.
It is accepted that the ancient Sun was considerably cooler than our local star is today, so much so that Earth a few billion years ago should have been a lifeless frozen ball. But scientists have also shown that the planet was not frozen—shallow seas warmer than any modern ocean abounded with microbial life. A recent study, detailed in the journal Nature, is a good example of the sometimes convoluted, even improbable reasoning is used to get a handle on earthly climates during eons long vanished. Using the fossilized impact dimples from rain drops that fell 2.7 billion years ago, researchers have calculated new limits on the density of Earth's atmosphere. This, in turn, has implications on the development of the ancient atmosphere and what role greenhouse gases may have played in warming the young Earth.
Carbon offsets, favored by PC Hollywood stars and green politicians alike, have been used by the rich and powerful as a way to make their energy wasting lifestyles appear to be OK from an ecological point of view. Al Gore and Leonardo DiCaprio have both used carbon offsets to greenwash their jet-setting travel on private aircraft. Airlines even offer the unwashed masses an opportunity to purchase carbon offsets before boarding a flight—you may not be able to fly like they stars but you can lie like the stars. Finally, a voice from the green ranks has spoken up to denounce carbon offsets for what they are: “carbon offsetting is without scientific legitimacy and is dangerously misleading.”
Just when it looked like the climate catastrophists had slunk back into well deserved academic obscurity, a new report in the journal Nature Geoscience has resurrected claims of Earth's impending climatic demise. A new computer climate study says to expect increases in temperature of up to 3°C by 2050, confirming or exceed predictions made by the IPCC reports. Can this model based report be considered any more accurate than previous attempts? Have modeling techniques suddenly improved? Or is this report's appearance in a major scientific journal the signal of a renewed round of scaremongering by eco-alarmists?
The dire results of anthropogenic global warming have become passé. Treated by the news media and climate alarmists as established scientific fact, the IPCC's vision of a dystopian future, a world ravaged by global warming, is feed to our children in school, TV shows and Hollywood movies. What is never mentioned is that even the IPCC's predictions encompass several ranges of possible outcome, all predicated on a seemingly simple but mysterious factor called climate system sensitivity. A recent study, published in the journal Science, used spatially more complete paleoclimate data for the Last Glacial Maximum (LGM) in an effort to improve previous estimates of climate sensitivity. The new results have not been widely reported in the news media because, according to the researchers, “these results imply a lower probability of imminent extreme climatic change than previously thought.”