I used to know David a long time ago, and he was not only bright, but extremely creative. I had not heard of the scenario he describes, but he probably knows what he's talking about. I recently read a book about the history of oxygen on the Earth, and sulfides are a key element in the history. Just because hydrogen sulfide is lurking there, though, doesn't mean that it will eventually come out. If combined with iron it can be buried as the mineral pyrite, as has happened for hundreds of millions years.

I'm sorry but denier like kano are talking utter fiction, they keep claiming Ocean acidification can't happen or isn't happening yet ask them what they base that on and you get the same old blogs.

Meanwhile the science and direct sampling show that pH has fallen steadily over the last 25 years.

http://www.igbp.net/images/18.30566fc614...

http://www.antarctica.gov.au/science/coo...

As for Brins comment, again it's a blog by a scfi writer I don't put much stock in them (from either side)

it should also be said that Brin does preface the text with "Worst Case Scenarios?"

Don't get your hopes up. But hydrogen sulfide does tend to form under the same conditions as methane. I doubt that we are going to experience a hydrogen sulfide doomsday. I doubt that either hydrogen sulfide or methane will exceed a few parts per million.

Like sulfur dioxide, hydrogen sulfide probably has a negative global warming potential, because it gets oxidized into sulfuric acid aerosols. In fact, sulfur dioxide is an intermediate step in this process. The negative global warming potential of hydrogen sulfide will be less than that of sulfur dioxide, because it takes the additional step to be oxidized into aerosols and because it is a greenhouse gas until it is oxidized. (So is sulfur dioxide.)

Anyway, since it probably has a negative global warming potential, hydrogen sulfide will probably at least partly cancel the warming effects of methane. But, on the other hand, hydrogen sulfide, and the resulting aerosols did not stop the end of the last glacial.

Sensationalistic speculation is not necessarily an Evil Alarming Marxist Greenie Reptilian plot.

But it is also not science.

it,s more of an issue with melting permafrost. there,s mega tons of trapped methane in permafrost, which is melting faster than in the past. the possible re;ease of methane ices in a future undersea mining venture is another nasty prospect. there are trillions of tons of frozen methane ices in very deep, cold waters. it is an untapped resource that is under consideration as a replacement for oil.

No. as you know our oceans contain a massive buffer of calcium and will not turn acidic

I am not going to lose sleep over it

As discussed in this editorial by noted hard science fiction author David Brin ( http://davidbrin.blogspot.com/2014/03/what-should-we-be-worried-about.html ), it's possible that changes in ocean acidity and currents could lead to massive outgassing of H2S from anaerobic layers of the deep ocean.

What are your thoughts on this editorial, and/or the phenomena it discusses?