"However, some have insisted that there is a paradox here – how can a forcing driven by longwave absorption and emission impact the ocean below since the infrared radiation does not penetrate more than a few micrometers into the ocean? Resolution of this conundrum is to be found in the recognition that the skin layer temperature gradient not only exists as a result of the ocean-atmosphere temperature difference, but also helps to control the ocean-atmosphere heat flux. (The ‘skin layer‘ is the very thin – up to 1 mm – layer at the top of ocean that is in direct contact with the atmosphere). Reducing the size of the temperature gradient through the skin layer reduces the flux. Thus, if the absorption of the infrared emission from atmospheric greenhouse gases reduces the gradient through the skin layer, the flow of heat from the ocean beneath will be reduced, leaving more of the heat introduced into the bulk of the upper oceanic layer by the absorption of sunlight to remain there to increase water temperature. Experimental evidence for this mechanism can be seen in at-sea measurements of the ocean skin and bulk temperatures."The RealClimate post then shows the experimental evidence [a single paper] for the remaining claim that greenhouse gases reduce the size of the temperature gradient to reduce heat flow from the oceans to the atmosphere, showing this graph:
 |
| Figure 2: The change in the skin temperature to bulk temperature difference as a function of the net longwave radiation. |
and stating:
"There is an associated reduction in the difference between the 5 cm and the skin temperatures. The slope of the relationship is 0.002ºK (W/m2)-1. Of course the range of net infrared forcing caused by changing cloud conditions (~100W/m2) is much greater than that caused by increasing levels of greenhouse gases (e.g. doubling pre-industrial CO2 levels will increase the net forcing by ~4W/m2), but the objective of this exercise was to demonstrate a relationship."According to the IPCC, a doubling of CO2 levels allegedly increases forcing by 3.7 Wm-2 at the top of the atmosphere and by only about 1 Wm-2 at the surface. The paper cited by RealClimate is measuring the effect of longwave forcing at the surface, therefore we assume 1 Wm-2 from doubled CO2 at the surface. Using the slope of the relationship, 0.002ºK (W/m2)-1, we find that doubling of CO2 concentrations could only reduce the temperature gradient 0.002*1 = 0.002ºC.
Furthermore, a reduced temperature gradient of 0.002ºC could at the very, very most result in an increase in bulk ocean temperature of 0.002ºC. In reality, this will never happen since the heat capacity of the ocean is more than 1000 times greater than the atmosphere, and therefore the ability for a doubling of CO2 to warm the oceans is essentially zero.
Related: New paper finds world's oceans have warmed only 0.09°C over past 55 years
This is a topic close to my heart because the air will only get warmer if the oceans do.
ReplyDeleteThe fact is that the changes in the temperatures of the ocean surfaces in the late 20th century cannot be attributed to CO2 in the air because the energy involved is far too small given the huge thermal capacity difference between air and water.
After much work I came to the conclusions set out in this article:
http://climaterealists.com/attachments/ftp/TheSettingAndMaintainingOfEarth.pdf
Regards,
Stephen Wilde
I'm thinking that rain falling through a warmer atmosphere, either directly onto the oceans, or via rivers, will be a major driver in transferring heat from sky to sea, anyone know of papers on this?
ReplyDeleteDoubt it - it's really the other way around
DeleteThunderstorms cool the surface
If rain and runoff into the ocean is warmer than previously, they will be a driver towards a warmer ocean. Thunderstorms would only have an increased effect of cooling the ocean if the rain was cooler, or (assuming you're right that thunderstorms cool the ocean) if thunderstorms were larger and/or more frequent.
DeleteSuggest you read Willis Eschenbach's paper
Deletehttp://wattsupwiththat.com/2010/07/24/willis-publishes-his-thermostat-hypothesis-paper/
http://wattsupwiththat.com/2011/06/07/further-evidence-for-my-thunderstorm-thermostat-hypothesis/
Now I know why you focused on thunderstorms when I was referring to rain (and any other precipitation). Willis' hypothesis looks like a reworked version of Lindzen's iris hypothesis, it doesn't really have a lot to do with the effects of precipitation from a warmer atmosphere on ocean temperatures.
ReplyDeleteWell, best of luck in finding papers to support your theory. The fact is the heat capacity of the oceans is over 1000 times greater than the atmosphere, so even if your theory was correct [it isn't] the oceans would not warm.
DeleteHeh, "New paper finds world's oceans have warmed only 0.09°C over past 55 years"
ReplyDeleteWhich means there's enough additional energy in the oceans to raise the atmospheres temperature by around 45C (allowing for warming only being in the top 2000m of the ocean), or, as the paper says "Ocean accounts for approximately 93% of the warming of the earth system that has occurred since 1955."
Heh, 45C that's a good one.
DeleteIt is a shame that you and other alarmists fail to understand that only shortwave radiation from that huge fireball in the sky is capable of warming the oceans, as shown by this post and others. It doesn't have anything to do with man-made CO2 and there is nothing that man can do to control the temperatures of the oceans, which in turn control the temperatures of the atmosphere.
Well, the average ocean depth is 4.3km, warming in the top 2000m is 0.09C, you recon the ocean has a thermal capacity 1000 times that of the atmosphere, so we get:
Delete2000m/4300m X 1000 X 0.09 = 41.40C
Oh, and the "alarmist" label probably isn't quite fair, I accept AGW, not convinced on CAGW
You think 0.09C warming of the oceans is going to warm the atmosphere 41C, but you are not convinced on CAGW. I see.
DeleteThe atmosphere would have to contain more than three orders of magnitude more heat than it does presently to budge the bulk temperature of the oceans. Even if it did, the oceans still would not warm since the heat would continue to be shed by both oceans and atmosphere by convection, conduction, and radiation.
Obviously I've not made myself clear, I'm simply illustrating that a huge amount of heat energy has in fact been transferred from air to sea, despite your belief that such heat transfer is virtually impossible
Delete"I'm simply illustrating that a huge amount of heat energy has in fact been transferred from air to sea"
DeleteNo, you have absolutely not shown that whatsoever, and it is painfully obvious from this post and others that essentially all heat transfer has been from Sun > Oceans > atmosphere > space.
I am now finished with your commentary. Got much better things to do. Bye
a_ray_in_dilbert_spce said:
ReplyDeleteMS, it is a shame that you [snip- unscientific emotional vitriol - see comment policy] have never managed to visit an ocean and see that there are phenomena such as wind and waves that continually break up the skin layer on the water and promote mixing and transport of heat.
[snip- unscientific emotional vitriol - see comment policy]
The paper cited by RealClimate is based on in-situ observations in the ocean that were subjected to "phenomena such as wind and waves that continually break up the skin layer on the water and promote mixing and transport of heat" Those effects are already incorporated in the slope of the relationship.
Deletea_ray_in_dilbert_spce: if you want your comments posted you will have to remove ad homs and not violate the comment policy.
http://tallbloke.wordpress.com/2012/09/10/met-office-1981-2010-averages-released/
ReplyDeletehttp://lasp.colorado.edu/sorce/images/instruments/sim/fig01.gif
ReplyDeletehttp://www.populartechnology.net/2009/07/truth-about-realclimateorg.html
ReplyDeletehttp://wattsupwiththat.com/2013/01/09/commitment-studies-belie-consensus-claim-that-a-persistent-high-level-of-temperature-forcing-cannot-cause-continued-warming/#comment-1196204
ReplyDeletehttp://wattsupwiththat.com/2013/05/03/ocean-heat-content-0-to-2000-meters-why-arent-northern-hemisphere-oceans-warming-during-the-argo-era/
ReplyDelete"A little-known fact is that the oceans are almost exclusively heated by sunlight (shortwave radiation) entering the surface layers."