Global Warming: Methane Could Be Far Worse Than Carbon Dioxide
Categories
Environment
Technology
Methane gas, abundantly trapped as a half frozen slush in the northern hemisphere's tundra permafrost regions and at the bottom of the sea may well be a ticking time bomb, says geologist John Atcheson in an article published by the
Baltimore Sun in December last year. Methane is about twenty times stronger as a
greenhouse gas than carbon dioxide. Since arctic warming seems to procede
faster than expected, there is a real danger that deposits of methane and similar gases trapped in normally frozen ground, may thaw out and "belch" into the atmosphere, wreaking havoc with our computer simulations of global warming.
According to Gregory Ryskin, associate professor of chemical engineering at Northwestern University, "explosive clouds of methane gas, initially trapped in stagnant bodies of water and suddenly released, could have killed off the majority of marine life and land animals and plants at the end of the Permian era" — long before dinosaurs lived and died.
Ruskin believes that methane may have been the driving force in previous catastrophic changes of the earth's climate, where 95 percent of marine species and 70 percent of land species were lost in - geologically speaking - the blink of an eye.
You may ask "what can I do about this?". There are some suggestions in an article posted on the
ZPEnergy site. Perhaps we should do everything possible to reverse the current trend towards global warming by burning less fossil fuels. The first target would be to go "carbon neutral", after which we should be figuring out ways to trap some of the excess carbon in the atmosphere and use it or store it in a non-gaseous form.
Using hydrogen instead of petroleum-derived fuels would be a first step, although we must find a way to produce the gas without burning more of the black stuff. Options range from the relatively inefficient direct-current electrolysis, solar hydrogen production at sea, the use of metal catalysts, high frequency electric currents, ultraviolet light and the action of bacteria which naturally produce hydrogen. It seems none of the technologies are quite ready to use, but there is no room for complacency.
Comes to mind the
methane atmosphere that was recently found to be prevalent on Saturn's moon Titan. Could there be a point of break in the equilibrium of atmospheric composition where a celestial body's gas cover can switch from a predominantly nitrogen/oxygen composition to predominantly methane? If so, we better watch our steps because human bodies as well as most known animal species do not run on methane. We might be in for an unpleasant surprise.
John Acheson asks:
"How likely is it that humans will cause methane burps by burning fossil fuels? No one knows. But it is somewhere between possible and likely at this point, and it becomes more likely with each passing year that we fail to act. So forget rising sea levels, melting ice caps, more intense storms, more floods, destruction of habitats and the extinction of polar bears. Forget warnings that global warming might turn some of the world's major agricultural areas into deserts and increase the range of tropical diseases, even though this is the stuff we're pretty sure will happen."
In what might have been an early warning, in 1986,
lake Nyos in Cameroon "burped" an amount of gases killing 1800 people, following a much smaller scale disaster on neighbouring lake Monoun two years earlier, which killed 37 people. While carbon dioxide has been fingered as the main culprit, there seems to have been a "fiery" component to the eruption indicating possible presence of combustible methane: "Skin discoloration found on some victims were tentatively interpreted as burns, but this diagnosis is still controversial. Witnesses on topographic highs report a loud noise originating from the lake and, in the case of lake Nyos, flashes of light visible over the lake".
Apparently, three dissolved gasses, carbon dioxide, hydrogen sulphide and methane come together and indeed, a project to
recover the methane from the waters of Lake Kivu, on Rwanda's north-western border, is in advanced stage of engineering. A
similar project is underway to de-gas lakes Nyos and Monoun in Cameroon.
While such isolated cases as the lakes in Africa may be amenable to direct engineering solutions, capturing the gasses and putting the methane to use as a fuel, we may not have such an easy solution ready for widespread methane outgassing from the warming of larger bodies of water and huge stretches of half-frozen tundra.
The only possible solution to stem the steady increase in atmospheric carbon dioxide would seem to satisfy our energy needs without burning hydrocarbons.
Ticking Time Bomb
John Atcheson
Baltimore Sun