Climate Change

[Alan V]

But, and here's the shocker, it has the opposite effect and actually helps cool the atmosphere...

Methane gas "cools" the atmosphere?  I'm still laughing!  (Or perhaps you're making a joke?)

I remember reading about certain deep ocean ecosystems which depended on leaking methane rather than on sunlight for their energy, so there is nothing inherently illogical about the idea that methane fertilization could boost ocean plant life.

However, according to the end of his article:

"But whether the findings apply to ocean seeps in other parts of the world is still a big question. Svalbard is in many ways a bellwether. Some methane seeps occur because the hydrates there are barely stable, and can be upset by slight changes in temperature and pressure. Globally, methane hydrate reservoirs may hold as much as one-third the carbon content of all fossil fuels. And with similar seeps along continental margins worldwide, there has been growing concern that methane emissions will dramatically increase as oceans warm. But Pohlman says one can’t count on the methane fertilizing effect being the same everywhere. Even in his study area, it’s apt to change with the seasons. He notes that his team’s data were collected in the constant sunlight of Arctic summer. During the dark polar night, photosynthesis would drop to nearly nothing, and methane emissions wouldn’t be offset by declining CO2."

So the observed methane fertilizing effect may be sensitive to temperature, light, and the rate at which methane is released, in which case it is also likely localized. Nor would it likely change the effect of methane seeping from melting permafrost, which will be a much bigger problem for us in the short run, since the melting of ocean hydrates won't likely progress too rapidly in the near future.

Nevertheless, climatologists will have to try to take the effect into account, just as they do with all negative as well as positive feedbacks.