June 22, 2016. As Alaska warms, methane emissions appear stable, study finds. phys.org.
One reason no increase has been seen may be that “Bacteria that produce methane and bacteria that consume methane will both become more active as temperatures get warmer,” said Steven Wofsy of Harvard University and co-author of the study. “Our study suggests that over the past 30 years, these processes have balanced out in the study area.”
Analysis of nearly three decades of air samples from Alaska’s North Slope shows little change in long-term methane emissions despite significant Arctic warming over that time period, according to new research published in Geophysical Research Letters, a journal of the American Geophysical Union.
In the new study, researchers from the Cooperative Institute for Research in Environmental Sciences (CIRES) at the University of Colorado Boulder, NOAA, NASA and other university partners examined 29 years of continuous, precision measurements of atmospheric methane and other gases from the NOAA Barrow Atmospheric Baseline Observatory, which is part of NOAA’s Global Greenhouse Gas Reference Network.
Reg Morrison. 18 Mar 2012. The Climate Debate Is global warming real? Here’s a fresh look at an old argument. http://regmorrison.edublogs.org
You should go to the link above, it’s got great PHOTOS and a whole lot more information.
EVOLUTION’S SHOTGUN Few are aware that the moderate climate we enjoy is largely a by-product of four billion years of bacterial activity. Even more poorly understood is the fact that one particular group of bacteria played a fundamental role in the evolution of life on Earth, and continues to do so. These are the principle producers of the crucial greenhouse gas, methane (CH4). They are among the world’s oldest life-forms, and without the injection of their heat-retentive waste gas into the young planet’s primitive atmosphere, Earth may have remained relatively lifeless. In considering the role played by these methane generators (methanogens) we need to be aware of methane’s greenhouse potential. Its four hydrogen atoms make it a reactive gas with a relatively short life, and it is commonly said to be some 20–23 times more heat-absorbent than carbon dioxide. But this figure only refers to its average potency over a time span of 100 years. Rarely mentioned, however, is the fact that during methane’s first decade in the atmosphere it has more than 70 times the potency of CO2, and during its first five years it has at least 100 times the greenhouse impact of CO2. Also neglected is the fact that vast quantities of methane are imprisoned in innumerable icy cages all around the world—in frozen tundra bogs and on the semi-frozen seabeds that fringe most of the world’s continental land masses. Commonly known as hydrates, these icy gas reservoirs alone hold some 3,000 times the volume of CH4 in the atmosphere. In an evolutionary sense this vast stockpile of potent bacterial gas represents one of evolution’s most effective culling mechanisms. There is strong evidence to suggest that eruptions of methane from this vast reservoir have contributed to massive extinction events several times in the past. It now appears that the sharp rise in the average global temperature over the past 30 years has once again begun to destabilise these hydrates, allowing this potent bacterial gas to escape into the seas and into the atmosphere.
METHANE RELEASE The massive reserves of bacterial methane that become trapped in marine and tundra ices for long periods of geological time may well represent the ultimate climate-control mechanism for the whole planet. There is good geological and biological evidence to suggest that there have been three or four occasions in the past when eruptions of methane into the atmosphere have sent global temperatures soaring upwards. On each of these occasions the geological and fossil record indicates an increase in atmospheric CO2 and a slow temperature rise, followed by an abrupt warming that can only be accounted for by a massive release of methane. Ominously, each of these methane eruptions also coincides with a mass extinction of life.
Humans are releasing methane too. Methane CO2+CH4 = Climate Chaos. General waste (landfill), Coal & Gas mining, Flood Irrigation, Cattle & Sheep
HYDRATES Many marine hydrates are locked in place by the icy abyssal currents that are generated by the sinking of cold, dense saltwater in polar regions. These abyssal currents gradually girdle the planet before surfacing and returning to their polar birthplace. This global circulation system is known as the thermohaline current. So long as these cold abyssal currents continue to flow, the world’s sea-floor hydrates generally remain frozen and stable. But whenever rising temperatures thaw the polar icecaps to any significant degree, the boyant melt-water pools on the surface, inhibiting the driving mechanism that runs the world’s thermohaline circulation system. This allows wind-driven fingers of warm surface water to reach down to the sea floor and release the methane from its icy cage. The last time this appears to have happened was about 55 million years ago, when according to the geological record, a discharge of 1,200–2,500 gigatons of methane caused a temperature spike of 8°– 10°C in polar regions and brought lush redwood forest to northern Greenland. Such polar warmth generated a deep-ocean temperature rise of 5–7°C in high latitudes, and appears to have switched off the the world’s thermohaline circulation starving the inert abyssal waters of oxygen. The carbon-loaded acidified seas caused a mass extinction of marine foraminifera. The temperature spike that occurred at this time appears to have been vastly greater and more abrupt than could possibly have been generated by the gradual rise in atmospheric CO2 that preceded it.1 The global temperature has risen almost 30 times faster than this during the past 30 years.