Re: The Methane Thread pt. 2
Posted: Mon 06 Nov 2017, 21:28:38
The ocean anoxia CH4 cannon is going to go off this century. Due to the area coverage of the anoxic zones and the volume of biogenic carbon cycling through them, we are looking at massive amounts of CH4 pumped from the oceans. All the attention is on the crysophere CH4. The non-cryosphere CH4 will make sure that most of the cryosphere CH4 is released.
People have no instincts about ocean biochemistry. It is a very sensitive system and the assumption that the current chemical regime will stay intact until 2100 or later is simply wrong. Now that we have direct evidence of a major error in the estimate of past ocean temperatures (on the high side), the ocean anoxia regime is guaranteed and the trends seen in observations are not to be dismissed.
The trend that will lead to a tipping point by around 2035, is the progressive shallowing of the ocean surface mixed layer together with increased O2 depletion at its base. The surface waters will still be oxic, but near subsurface waters will be anoxic and the detritus rain that today is remineralized in association with CO2 release will be remineralized with CH4 and H2S release.
https://www.sciencedaily.com/releases/2 ... 063957.htm
H2S possibly contributed as the primary agent to the largest mass extinction 251 million years ago. I am going to go out on a limb and say that it would be physically impossible for it not to have been a prime factor.
H2S is a greenhouse gas:
H2S absorption intensity
but it is not as potent as CH4. Nevertheless, a layer of H2S above the ocean surface will only hammer in the last nail into the coffin.
People have no instincts about ocean biochemistry. It is a very sensitive system and the assumption that the current chemical regime will stay intact until 2100 or later is simply wrong. Now that we have direct evidence of a major error in the estimate of past ocean temperatures (on the high side), the ocean anoxia regime is guaranteed and the trends seen in observations are not to be dismissed.
The trend that will lead to a tipping point by around 2035, is the progressive shallowing of the ocean surface mixed layer together with increased O2 depletion at its base. The surface waters will still be oxic, but near subsurface waters will be anoxic and the detritus rain that today is remineralized in association with CO2 release will be remineralized with CH4 and H2S release.
https://www.sciencedaily.com/releases/2 ... 063957.htm
H2S possibly contributed as the primary agent to the largest mass extinction 251 million years ago. I am going to go out on a limb and say that it would be physically impossible for it not to have been a prime factor.
H2S is a greenhouse gas:
H2S absorption intensity
but it is not as potent as CH4. Nevertheless, a layer of H2S above the ocean surface will only hammer in the last nail into the coffin.