Scientists have always thought that the vast majority of ice contained in the Antarctic ice cap was formed from frozen precipitation. Recent research has revealed that this is not totally correct. Over a large fraction of East Antarctica, the deepest part of the ice sheet contains ice that did not originate as surface snow but developed when subglacial meltwater was frozen onto the underside of the ice sheet. The amount of ice involved is much larger than the estimated volume of Antarctic subglacial lakes and may even exceed the volume of all glaciers on Earth outside of the two polar ice sheets. Current computer models predict that subglacial water escapes toward the ocean. These new findings indicate that water from areas of basal melting actually migrate to areas of basal freezing, something not accounted for by current ice sheet models. To scientists' surprise, the East Antarctic Ice Sheet is getting thicker from the bottom up.
Given the ongoing controversy over global warming the question of whether humans can change Earth's climate is a familiar one. Lost in the fight over anthropogenic global warming is a more subtle and possibly more important question—how has climate changed people. In recent decades, the fossil record of hominin evolution and behavior, though still incomplete, has improved greatly. Triggered by a recent National Research Council (NRC) report, a perspective article in the journal Science poses the question, “did climate change shape human evolution?”
Fluctuations in surface melting are known to affect the speed of glaciers and ice sheets, while the contribution of glaciers and ice caps to global sea-level rise is uncertain at best. Much has been made of the “accelerating” loss of ice from the Greenland glaciers. Over the past decade, Arctic sea ice retreated substantially during the summer months, and some predicted that the ice loss could be irreversible, a tipping point that would boost global warming. A number of new papers in Nature, Geophysical Research Letters and Nature Geoscience, shed new light on these subjects, and the answers are not the ones usually heard in the media.
Around 19,000 years ago, oceanic conditions underwent dramatic changes that coincided with a shift in global climate, marking the onset of the Holocene warming. In the North Atlantic, major changes in the Meridional Overturning Circulation (MOC), which carries warm and highly saline surface water north to cooler regions, played a substantial role in regulating climate and levels of atmospheric carbon dioxide. Scientists are now convinced that the ocean absorbed, stored, and released vast quantities of carbon in the past, playing a major role in the end of the last Pleistocene Ice Age glacial period. Understanding the ocean's role in the past is important to understanding how it may influence climate in the future. A new report in Science shows that the MOC experienced a series of abrupt changes that lasted from decades to centuries, and may have stored and released more CO2 than previously thought.
Climate alarmists have been slow to learn that their over-reliance on computer models and unproven theories has harmed their public credibility. In an attempt to counter the richly deserved bad press that climate science has been garnering these days, a number of global warming true believers are trying a different, more fact based approach to scaring the public. One such attempt recently appeared in the journal Science—not as a paper describing original research but as a perspective article. In it, a Senior Scientist at the National Center for Atmospheric Research, in Boulder, Colorado, attempts to “weave together” some carefully selected “threads in the discussion of climate” to arrive at a very familiar and unconvincing conclusion.
Time after time, the public has been harangued by climate change “experts” predicting all form of devastation due to anthropogenic global warming. The Greenland and Antarctic glaciers will melt, as will the sea ice covering the Arctic Ocean. Temperatures will rise by 2-6°C, perhaps more in higher latitudes. Weather patterns will shift, there will be droughts and torrential monsoon rains, cyclones will increase in intensity—where will it all end? Here's a thought, we might find the world a nicer place after a bit of global warming. In fact, given the general cooling trend seen over the Holocene (the period since the last glacial period ended around 14,000 years ago) and the Cenozoic (the time since the dinosaurs died, around 65 million years ago) human CO2 may be, in some small way, the only thing delaying another devastating ice age.
To ring in the new year, The Resilient Earth presents a collection of recent journal and news articles regarding climate science. Some are about actual science and others are more in the way of commentary on the state of global warming. New discoveries continue to be made, though the climate change faithful stubbornly refuse to abandon the party line: Earth's temperature is going to rise dangerously and humanity is to blame. Perhaps the most interesting development is that a number of green advocates have given up on avoiding global warming, deciding instead to stress the unfair social impacts that climate change will supposedly cause. At the end of 2010, here is a snapshot of the state of the climate change debate.
Much has be written and even more said about stopping climate change. The total foolishness of such a quest is obvious to anyone with even the most cursory understanding of Earth's climate over the Past 65 million years. The more science learns about the ever changing nature of climate the more capricious nature appears and the less significant the labors of H. sapiens are revealed to be. To place the ludicrous arguments and unsubstantiated fears of climate catastrophists in perspective, it is instructive to survey Earth's climate since the demise of the dinosaurs—the geological time period called the Cenozoic Era. During this long span of time, Earth's climate has undergone a significant and complex evolution. If one truth has been discovered by human science it is that Earth's climate is always changing, driven, as one set of researchers put it, by trends, rhythms and aberrations—the mechanisms of climate change.
You know, in science, there was once this thing we called the Theory of Multiple Working Hypotheses. Anathema (a formal ecclesiastical curse accompanied by excommunication) in modern climate science. So, in juxtaposition to the hypothesis of future global climate disruption from CO2, a scientist might well consider an antithesis or two in order to maintain ones objectivity. One such antithesis, which happens to be a long running debate in paleoclimate science, concerns the end Holocene. Or just how long the present interglacial will last.
A new paper, penned by a group of known warmist scare mongers, claims to have proof that CO2 is the control knob that regulates Earth’s temperature. Andrew A. Lacis, Gavin A. Schmidt, David Rind, and Reto A. Ruedy, all from NASA's Goddard Institute for Space Studies, are boasting they have experimental proof that “carbon dioxide is the single most important climate-relevant greenhouse gas in Earth’s atmosphere.” Even though this climate alarmist cabal admits that H2O, in the form of water vapor and clouds, accounts for 75% of greenhouse warming, they still claim that that CO2 is king. Why? Because water's contributions are supposedly caused by feedbacks involving carbon dioxide. How have they proven that? By fiddling around with the same biased computer climate models that their other fictitious claims are based on.
Evidently 2010 is the International Year of Biodiversity, a year long celebration of Earth's glorious variety of species and ecosystems. Unfortunately, the 1992 Convention on Biological Diversity (CBD) has failed to meet its ambitious goal: a significant slowdown in biodiversity loss by 2010. The AAAS journal Science has acknowledged this celebration with special News Focus section and a Review article. “After failing to meet its major conservation goal, the Convention on Biological Diversity is setting new targets for stemming the loss of species,” its lead article states. But the news is not all bad. In some countries, conservation efforts have helped species recover and reportedly large-scale deforestation in the Amazon has declined by 47.5% over the past 12 months. With eco-alarmists shifting their panicked attention from climate change to biodiversity, it is time to look at the facts.
Even with all of the recent scandal surrounding the purveyors of climate change pap, many in the “news media” continue to crank out party-line articles blaming all of Earth's ecological woes on humanity. After decades of trying to alarm the public over a human caused “sixth mass extinction” and more recently, dwindling diversity, some in the media just can't let go of AGW as the root of all evil. A perfect example of this appeared recently in the font of misinformation that is Yahoo News. Blaming every human activity from hunting to climate change, science writer Jeremy Hsu has once again raised the specter of that old shibboleth, the Anthropocene Epoch. This is all a part of a developing trend to elevate falling species diversity to crisis level, mainly because the world's eco-activists need a replacement issue for climate change.
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.
Driven by a constantly expanding need for electricity, Chile is considering building seven new dams and a transmission line through its southern wilderness. This isolated land of condors and monkey puzzle trees is home to the third largest reserve of frozen freshwater in the world—the Southern Ice Field. Critics say the environmental risks have not been fully examined, and the risk to southern Chile's unique ecosystems is unacceptably high. Proponents of the dam project argue that hydroelectricity is a clean source of energy, just waiting to be tapped. Chile needs the 3500 MW/yr of power to meet its development goals and lacks indigenous oil or coal reserves. Moreover, the electricity from the dams would displace dirty generation, greatly reducing Chile's greenhouse gas emissions. Give all the benefits, why are so many people, within Chile and without, so opposed to the dams—opposed to the point of preferring new coal plants?