Anthropogenic CO2 is emitted to the atmosphere first, then a good part of it is absorbed by the ocean. An estimate of the oceanic anthropogenic sink for the period 1800-1994 shows that 48% of anthropogenic carbon emitted during this period is in the ocean (Sabine et al., 2004). In terms of warming, atmosphere warms first as an effect of the increased trapping of longwave radiation. Again, the ocean comes to the rescue absorbing part of the anthropogenic heat (I don't have a number for this, I'll look into it). After this initial atmosphere-to-ocean flux, both carbon and heat become part of complex and dynamic feedback cycles between atmosphere and ocean. One of them is what you mention, the effect of warming on the CO2 solubility in sea water.
Are there ocean temperature variabilities independently of atmosphere behaviour? If the ocean will be warmed indepedently of atmosphere interaction, the old CO2 which is included in the ocean will be released.
The source of heat for the ocean are the atmosphere and the sea-floor. I don't think the second one is big enough to cause significant reductions in CO2 solubility in sea water. Maybe locally, around hot-spots of geothermal activity but I don't think it has a global impact on the carbon cycle, at the timescsales relevant for human-induced climate change, at least. At geological timescales, to be honest, I have no idea.
Human activities are adding energy to the ocean-atmospheric interface. Some of thta extra energy immediately goes into the atmosphere where it quickly mixes away (i.e. build a fire, local heating only, 10 feet away, air is mixed).
What goes into the ocean works much more slowly because of the gigantic heat capacity of water.
As a result of this, changes in the surface temperature and/or temperature profile of the ocean take 100-1000 years to occur in a significant way. So yes, continued heating of the oceans lessen the ability for CO2 to get mixed into the surface ocean waters (the solubility effect) - the other effect which is a warming ocean exudes more CO2 from its various storage reservoirs occurs over much longer timescales.
The 2012 paper by Leavitus etall is a very good quantitative study of ocean heating
Yes the CO2 is emitted to the atmosphere and is later a part of it is sequestered to ocean warmer ocean will lower the CO2 uptake. The release of CO2 from ocean is not a very likely scenario in normal circumstances.
Heating starts in the atmosphere and is then transferred to the ocean. Heat enters the ocean by diffusion and mixing at the surface, and by thermohaline circulation for deep water. Recent evidence suggest that Antarctic Bottom Waters are already showing signs of warming. http://onlinelibrary.wiley.com/doi/10.1002/2014GL059923/abstract
If Bottom Waters are already showing signs of warming, what is the feedback of the ocean heating in the future? Will we observe increased heat exchange between ocean and atmosphere with a probably possitive heat forcing to the first meters of atmosphere and intensification of global warming effect? Because according to this assumption we will have a significant increase of total energy budget in the system of Air-Sea.
the heat stored in Antarctic Bottom Waters is likely to stay there for thousands of years, while the heat stored in the main thermocline is the fraction that will play a role in ocean-atmospheric feedbacks. That fraction will stay there (and increase) as long as the radiative forcing increases as a result of increasing atmospheric CO2. What happens if we stop CO2 emissions? An interesting paper about this, by Frolicher et al., 2013:
@ Raffaele: Great paper and I salute the expert :-) I have a question. I understand that AADW is slightly fresher than intermediate water but is more dense because it is so cold. How much does it have to warm before the buoyancy of deep and intermediate waters converge. And what happens?
David, I don't have an answer to neither of your two questions. However, AABW is formed mostly on the continental shelf where it starts sinking and mixing with other water masses and finally it reaches the bottom because it has a higher density than the rest of water masses, among them AAIW. The observed warming in AABW reflects changes occurring in its formation on the Antarctic shelf and during the complex mixing once it has left the surface. This changes are not enough to stop their formation, I guess. If and when these changes were to become strong enough to give AABW a density similar to AAIW, I guess there won't be any more formation of AABW, shutting the abyssal ocean off from any direct contact to the atmosphere.
This is absolute that oceans warmed first and influence to weather because water has a higher specific heat value and influences on the air above the water surface. So weather cant influence on the ocean water temperature. Factors due to global warming first increase ocean water temp.
@ David (Considering warming and density changes and how is influences the overturning)
Quite recently a publication by a group in Kiel under the title "Abyssal ocean warming around Antarctica strengthens the Atlantic overturning circulation" has analyzed their numerical model. Please see DOI 10.1002/2014GL059923 (http://dx.doi.org/10.1002/2014GL059923). The abstract says: "The abyssal warming around Antarctica is one of the most prominent multidecadal signals of change in the global ocean. Here we investigate its dynamical impacts on the Atlantic Meridional Overturning Circulation (AMOC) by performing a set of experiments with the ocean-sea ice model NEMO-LIM2 at ½° horizontal resolution. The simulations suggest that the ongoing warming of Antarctic Bottom Water (AABW), already affecting much of the Southern Hemisphere with a rate of up to 0.05°C decade−1, has important implications for the large-scale meridional overturning circulation in the Atlantic Ocean. While the abyssal northward flow of AABW is weakening, we find the upper AMOC cell to progressively strengthen by 5–10% in response to deep density changes in the South Atlantic. The simulations suggest that the AABW-induced strengthening of the AMOC is already extending into the subtropical North Atlantic, implying that the process may counteract the projected decrease of the AMOC in the next decades."
I agree with David that the warming starts in the air from the extra greenhouse CO2 gas and is transferred to the oceans. The oceans evaporate more, so we see an unprecedented increase in humidity worldwide that leads to health problems such as colds, asthma, blocked air pipe - this winter the demand for oxygen to help mostly old people to breath exceeded all records.
From the earth's history, the release of abundant CO2 from volcanoes contributed to the fatal Global Warming 250 million years ago - The Great Dying or the Permian Mass Extinction that killed over 90 % of all species (NOT the death of dinosaurs, that was mush later). Apparently, it triggered the release of methane from the ocean floor - it is happening in the Atlantic already as a result of our own Global Warming event - and the two gases together (CO2 and methane, both are "greenhouse" gases) raised the temperature some 10 degrees higher - that passed the Death sentence.
Today, we all know where this extra CO2 gas comes from - burning the dirty fossil fuels -, so if we don't want serious changes in the air, change into other forms of energy before it gets too late...
The oceans are about 850 times more dense than the atmosphere and both are fluids. About 97% of the excess heat produced by surface activities ends up in the oceans.
The oceans transfers this excess heat into the atmosphere through various processes on various timescales.. For the most part, the oceans have served as a giant buffer but buffer space is running out.
Nice answer... The oceans are directly heated by the sun, and by IR radiation from GHG the atmosphere. On average more energy enters the ocean surface (e.g. at night) from the atmosphere than directly from the sun. The buffer analogy is spot on. Great summary here.