Even though climate scientists have not been able to identify all of the factors involved in climate regulation, or even develop trustworthy values for the ones they do know about, some eco-activists are proposing that we actively try to alter Earth's climate. Schemes to purposefully alter the environment on a global scale are called geoengineering, and it has been proposed as a way to counter act anthropogenic global warming and its side effects. The two main geoengineering options are limiting incoming solar radiation, or modifying the carbon cycle. Two articles, one in the Proceedings of the National Academy of Science and another in Nature Geoscience, report that controlling climate through geoengineering would be difficult, if not impossible, and may do more harm than good. At a time when we cannot even predict how climate will change on its own, proposals to engineer climate change are best left as thought experiments.
In Europe and North America, the development of nuclear power effectively halted after the March 1979 accident in Pennsylvania at Three Mile Island. Until recently the building of additional nuclear reactors in most developed nations was unlikely. Meanwhile, the greatest hope of the alternative energy industry has been wind power, but people around the world are starting to question the safety and effectiveness of large wind farms. As the public's infatuation with “green” energy has faded, the resurgent nuclear power industry has been quietly ramping up its efforts to provide the energy the world will need in the future. Even ecological activists have come to realize that nuclear is the only viable option to fossil fuels. As a result, a nuclear surge is underway, with 52 new reactors under construction around the world and more in the planning stages. This about face in energy policy amounts to nothing less than a nuclear renaissance.
It is well known that carbon dioxide cannot directly account for the observed increase in global temperature over the past century. This has led climate scientists to theorize that many feedback relationships exists within the climate system, serving to amplify the impact of rising CO2 levels. One of these is the impact of rising temperature on the ability of the ecosystem to absorb CO2. The temperature sensitivity of ecosystem respiratory processes (referred to as Q10) is a key determinant of the interaction between climate and the carbon cycle. New research, recently published in the journal Science, shows that the Q10 of ecosystem respiration is invariant with respect to mean annual temperature, and independent of the analyzed ecosystem type. This newly discovered temperature insensitivity suggests that climate sensitivity to CO2 is much smaller than assumed by climate models.
Black carbon is generated from burning both fossil fuels and biomass. Black carbon aerosols absorb solar radiation and are purported to be a major source of global warming. A recent study claims that the extent of black-carbon-induced warming is dependent on the concentration of sulfate (SO2) and organic aerosols—which reflect solar radiation and cool the surface—as well as the origin of the black carbon. The ratio of fossil-fuel-based black carbon to SO2 emissions has increased by more than a factor of two during the twentieth century, and the portion of black carbon from fossil fuels has increased threefold. This could account for a 30% increase in global warming from black carbon, which may account for a quarter of the warming usually attributed to CO2. Even worse, black carbon may be causing millions of deaths among those who have to breath it. Far from being green, climate science's demonizing of CO2 is damaging the pursuit of sound environmental policy.
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.
Because of the ubiquitous computer chip, it has become much easier to construct models of natural phenomena than to study them in situ. This is a growing problem for science because it leads to an over dependence on modeling and diminishes motivation for actually getting out into the big messy world. A pair of articles in Nature Geoscience, focused on the ocean's nitrogen cycle, serve to underscore the problems that can arise when multiple models disagree with each other and with nature. More proof that computer models do not provide scientific evidence, just tales from the silicon chip.
For those who believe in anthropogenic global warming, carbon dioxide is public enemy number one. They warn that CO2 must be avoided at all costs or Earth will heat up uncontrollably causing all sorts of ecological havoc. One proposal for avoiding global warming is the sequestration of CO2 by trapping it at combustion sites or extracting it directly from the air. Supposedly, such sequestration could help avoid a large rise in atmospheric CO2 from the use of fossil fuels, avoiding the hellish fate that surely awaits mankind otherwise. Referred to as carbon capture and storage (CCS), the coal industry has seized on sequestration as a way to get greens off their backs and stay in business. However, it is not clear how effective different types of sequestration and associated leakage are in the long term, or what their consequences might be. A recent paper takes a critical look at the sequestration option.
According to a new report in Nature Geoscience, scientists are beginning to realize that previously ignored aspects of the terrestrial biosphere can act as key regulators of atmospheric chemistry and climate. Not only that, changes in the biosphere can happen quickly—in the course of a few decades. “Although interactions between the carbon cycle and climate have been a central focus, other biogeochemical feedbacks could be as important in modulating future climate change,” states the report. Because a number of these feedbacks can have a cooling effect, the impact on global warming predictions could be earthshaking. The problem is, these feedbacks are only poorly understood and they are so interrelated that modeling them will be difficult, if not impossible.
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.
According to a recent paper, human actions may have caused Earth's climate to warm much earlier than previously expected. In an article to be published in Geophysical Research Letters, and widely reported in the media, around 15,000 years ago, early hunters were a major factor in driving mammoths to extinction. Supposedly, this die-off had the side effect of heating up the planet. This is an interesting conjecture, since a letter just published in Nature Geocience reaches the opposite conclusion regarding climate and the mammoths' decline. This mammoth confusion illustrates the uncertain and even contradictory evidence that abounds in climate science.
The ocean is Earth's largest single sink for CO2 outside of the planet's crust itself. Simple sea creatures depend on carbon dissolved in the ocean's water for their existence, and their actions create a biological carbon “pump” that removes vast quantities of CO2 from the atmosphere. Large amounts are suspended in the water column as dissolved organic carbon (DOC), and each year the ocean's biological pump deposits some 300 million tons of carbon in the deep ocean sink. New findings have revealed that massive amounts of carbon are converted into “inedible” forms of organic carbon that remain out of circulation for thousands of years, effectively sequestering the carbon by removing it from the ocean food chain. According to Jiao Nianzhi, a microbial ecologist here at Xiamen University, the amount stored is tremendous: “It's really huge. It's comparable to all the carbon dioxide in the air.”
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.
With the oil disaster in the Gulf of Mexico emboldening all the denizens of the eco-underground, some voices are once again calling for increased production of biofuels—ethanol and biodiesel—and accelerated research into clean coal. Ignoring the fact that biofuels take as much energy to produce as they provide and that they are only competitive with heavy government subsidies, biofuel boosters are again trying to sell their snake-oil to the public. But the single most damning aspect of biofuel production is the exorbitant amount of water it takes to cook-up a gallon of the stuff. Now it appears that the other great energy scam, clean coal, will also increase water usage—by a whopping 80%. With the world facing a real water crisis in the near future, the last thing any government should be doing is wasting their citizens' money on are “green” energy scams that are really just subsidies for coal companies and big agribusiness conglomerates.
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.