FYI here was my take as a jurno on the plankton decline when the Nature paper came out – plus dead zones & acidification – and speculates on how loss of plankton may impact on cloud formation ?…(Kind of scared myself re-reading it)

http://stephenleahy.net/2010/08/06/ocean-losing-its-green-planets-life-support-system-in-decline/

No, I’m not getting the articles confused. I assumed this was what prompted your comment ‘we are all going to die’. Let me dial it back.

The problem is that the Sci American/ Nature article confirms the NASA satellite measurements, and extends it back in time. Causality is weak, but I think it would be prudent given the finding to examine possible changes in the partial pressure of oxygen over this period, although my reasons for doing so are probably alarmist.

What I am getting at, is that a decline of 40% and growing in ocean produtivity may lead to a reversal of evolutionary history, ala the Eidacarian (if indeed it is a unique multicellular radiation).

It’s been hypothesized that photosynthesis altered the earth’s atmosphere from reducing to oxidizing, and is potentially the variable explaining the evolution of multicellular life. Eliminate oxygen and it’s not possible.

http://palaeo.gly.bris.ac.uk/Palaeofiles/Cambrian/triggers/extrinsic/extrinsic.html

http://life3.beyondgenes.com/

Second, there a narrow percentage of oxygen in the atmosphere necessary for maintaining oxidative respiration, I think the ranges is 20% to 26%. (I cannot recall a cite for this, but understand that above 26% and spontaneous ignition would be sustained; and below 20% only diffusion of oxygen for cellular activity can be sustained for aerobes)

[And before someone raises the hyperoxic conditions of the Paleozoic that are inferred responsible for large insects (e.g. the Caboniferous dragonfly with the three foot wingspan), note that the partial pressure of oxygen was near the upper limit of the bound, not beyond.]

The primary production of the ocean is the largest aggregate of carbon dioxide fixation on the planet, and impaired could result in an oxygen deficet that could move the atmospheric partial pressure of oxygen downwards over time. I doubt terrestrial ecosystems could fill the gap.

Mike

Anybody trying to measure changes in the partial pressure of atmospheric oxygen for the period? That’s the shoe I am waiting to see drop. (FWIW this is about the most f/u’ed piece of science news I have seen in a while–the mass extinction from this would put the close of the Permian to shame.)

You may also want to see this:

http://www.mindfully.org/Water/2003/Phytoplankton-Decline-Ocean6oct03.htm

Mike

The part about people being stupid is self evident, I’m afraid.

Mike