Wegener Institute - Increased Water Temps May Cut Ocean CO2 Uptake - Science Daily

[hatrack]

EDIT

Atmospheric CO2 enters the ocean at the sea surface. To allow for continued uptake, it has to be transported to deeper layers. “One of the mechanisms responsible for this transport to depth is the biological carbon pump”, explains Julia Wohlers from IFM-GEOMAR, the first author of the study, which has just been published in PNAS. In spring, when temperatures rise and light conditions improve, planktonic algae start to build up biomass using CO2 and nutrients. After the algae have died, a fraction of this biomass sinks to greater depth – taking with it the photosynthetically bound carbon.

To investigate how this system will change in response to surface-ocean warming, the scientists from Kiel have enclosed natural plankton communities in eight tanks of 1,400 litres each. The communities were exposed to different temperatures, which corresponded to the warming scenarios projected by the International Panel of Climate Change (IPCC) until the year 2100. In these “miniature ecosystems” the build-up and decline of the spring plankton bloom was monitored over a period of one month. “As expected, the metabolic rates of all components of the plankton community were accelerated with increasing temperature. What came as a surprise to us was that the plankton consumed up to one third less CO2 at elevated temperatures. Ultimately, this may cause a weakening of the biological carbon pump”, says Prof. Ulf Riebesell from IFM-GEOMAR, the principal investigator of the study.

The reason for this weakening: While the photosynthetic build-up of biomass by planktonic algae shows only a minor response to warming, its consumption by bacteria strongly increases with rising temperature. This causes a greater portion of algal biomass to be degraded before it can sink to deeper waters. Thus, more CO2 is retained in the surface layer, which, in turn, will take up less CO2 from the atmosphere.

“This study underscores the importance to improve the incorporation of biological processes and feedbacks in Earth system models”, Julia Wohlers points out. For a global estimate of the magnitude of the observed feedback, however, it is still too early at this stage. “Data in this research area are still sparse and further research efforts are needed to fill this gap of knowledge”, says Wohlers.

EDIT/END

http://www.sciencedaily.com/releases/2009/04/090408074403.htm

[eppur_se_muova]

1. Damn, where are the NEGATIVE feedback loops?

Everything seems to be working against stability.

[Dead_Parrot]

7. we cut them down to make paper. nt

[XemaSab]

2. So is this good news or bad news?

Would this serve to protect the oceans, destroy the oceans, or just totally hose us even more than we were already hosed? :shrug:

[phantom power]

3. Sounds like it will alter the microbial base of the food chain. Surface to floor.

[hatrack]

4. Acidification slows, but more CO2 remains in the atmosphere

Pretty much rack vs. iron maiden . . . . take your pick.

[XemaSab]

5. Iron Maiden?

http://www.youtube.com/watch?v=cE4FHolkO94&feature=related

:headbang:

[Dead_Parrot]

6. That would be "totally hose us"

One of the few things that takes CO₂ out of the atmosphere (via the upper ocean) will pack in, leaving us with a cooking planet and no food chain for the ocean.

We are really fucked if this pans out.