Pending disappearance of Arctic ice has one more knock on effect.
Complete article quoted, as it's a 'media release'.
Potential implication of Arctic ice loss becomes more dire with each passing bit of data I seem to find.
http://www.sams.ac.uk/...
Media release 17 September 2009
Arctic sea ice pumps 50% more carbon dioxide into the oceans
Arctic sea ice plays a critical and hitherto unknown role in the removal of the greenhouse gas, carbon dioxide (CO2) from the atmosphere, as revealed in a study just published by an international research team that includes Prof. Ronnie Glud of SAMS.
The Nordic Seas have some of the highest uptake rates of carbon dioxide in the global ocean. Prior to this study, the mechanism by which the CO2 is absorbed into the ocean was believed to be driven largely by biological draw-down: micro-organisms remove inorganic carbon compounds from the water column, encouraging more CO2 to dissolve from the atmosphere.
.. in this study, the researchers have found that sea ice itself plays an important role in CO2 capture, effectively pumping this potent greenhouse gas out of the atmosphere. As sea ice forms, it rejects brine, rich in inorganic carbon compounds (derived from atmospheric CO2), into the underlying seawater, a process further stimulated by carbonate precipitation within the sea ice. The summer sea ice melt liberates water which is strongly depleted in CO2. The very low concentration of CO2 in this surface water then drives the extraordinary uptake of CO2 from the atmosphere.
Professor Glud of SAMS said: "The implications of these findings are immense – we know that the Nordic Seas have very high uptake rates of CO2 from the atmosphere. Until now we did not appreciate the importance of sea ice in this process."
"Current climate models do not factor in the role of sea ice, so our findings will require a reevaluation of the relationship between temperature changes and oceanic CO2 uptake."
The team took samples from 50 separate locations on the Arctic sea ice. As well as recording snow and ice thickness and temperature within the ice, they removed ice blocks and cores to examine the inorganic carbon concentration and CO2 captured within the ice lattice itself.
By entering various parameters into their model (including sea ice cover, partial pressure of CO2, and export rate of sea ice from the Arctic Ocean), the researchers have revealed that sea ice itself, during formation and melting, increases the seasonal uptake of CO2 in the region by 50%.
Prof. Glud continued:
"The total loss of summer sea ice from the Arctic, predicted to occur within the next few decades, may have dramatic effects on the ability of the Arctic Ocean to sequester CO2 from the atmosphere.
"We could see further increases in CO2 accumulation in the atmosphere, if reductions in this "the sea-ice pump" are not compensated for elsewhere."
The paper:
Rysgaard, S., J. Bendtsen, L. T. Pedersen, H. Ramløv, and R. N. Glud (2009), Increased CO2 uptake due to sea ice growth and decay in the Nordic Seas, J. Geophys. Res., 114, C09011, doi:10.1029/2008JC005088.
If this was posted earlier here, I missed it.
Combined with other factors, the potential loss of a CO2 sink of this size could serve to accelerate local atmospheric concentration of CO2 in the Arctic region, adding to the process local warming. As the effect of losing this 'sink' for carbon spreads, it will serve to intensify global climate change.
http://nsidc.org/...
July 6, 2010
Rapid ice loss continues through June
Average June ice extent was the lowest in the satellite data record, from 1979 to 2010. Arctic air temperatures were higher than normal, and Arctic sea ice continued to decline at a fast pace. June saw the return of the Arctic dipole anomaly, an atmospheric pressure pattern that contributed to the record sea ice loss in 2007.