Enter a long narrative song and dance (absent experimental science to test the narrative of course) about
ocean cool skin layer being the man in the middle.
Adding further greenhouse gases to the atmosphere warms
the ocean cool skin layer, which in turn reduces the amount of heat flowing out of the ocean.
Kevin, even with greater evaporation, when one considers all the energy fluxes into and out of
the ocean cool skin layer, as long as the change in net energy flux causes the cool skin to warm, the temperature gradient between the cool skin layer and the bulk ocean below it will decrease.
Not exact matches
When greenhouse gases increase, more longwave radiation is directed back at the
ocean surface, which warms the
cool -
skin layer, lowers the thermal gradient, and consequently reduces the rate of heat loss.
So the mechanism should cause a decline in
skin temperature gradients with increased cloud cover (more downward heat radiation), and there should also be a decline in the difference between
cool skin layer and
ocean bulk temperatures - as less heat escapes the
ocean under increased atmospheric warming.
Increased warming of the
cool skin layer (via increased greenhouse gases) lowers its temperature gradient (that is the temperature difference between the top and bottom of the
layer), and this reduces the rate at which heat flows out of the
ocean to the atmosphere.
As I understand this article, the decrease in temp gradient in the
cool skin layer is what allows increases in atmospheric CO2 concentrations to further warm the
oceans.
The rate of flow of heat out of the
ocean is determined by the temperature gradient in the «
cool skin layer», which resides within the thin viscous surface
layer of
ocean that is in contact with the atmosphere.
Because of their effect on lowering the temperature gradient of the
cool skin layer, increased levels of greenhouse gases lead to more heat being stored in the
oceans over the long - term.
The same concept applies to the
cool skin layer - warm the top of the
layer and the gradient across it decreases, therefore reducing heat flowing out of the
ocean.
The rate of flow of heat out of the
ocean is determined by the temperature gradient in the «
cool skin layer»
Perhaps you can explain to me how a micro-physical effect, such as the reduced thermal gradient in the
cool skin layer, is simulated in the
ocean models?
Nice misconception you have going there but the real argument is that CO2 can lower the temperature gradient of the
cool skin layer, which slows the heat loss to the atmosphere and increased levels of greenhouse gases lead to more heat being stored in the
oceans over the long - term.
The downwelling radiation from GHG's is a major factor in preventing the surface of the
skin layer from
cooling and this keeps the
ocean warmer.
This results in what's known as the
cool skin layer of the
ocean which is the topmost 1 millimeter being about 1C
cooler than the bulk mixed
layer (~ 300 meters) below it.
The appropriately named «
cool skin layer» of the
ocean is there because of it.
One effect among many is to reduce the temperature gradient within the
skin layer of the
ocean and hence reduce the rate of
cooling of the upper mixed
layer (the first few meters of which are warmed by the Sun) to the atmosphere and also, radiatively, through the atmospheric infrared window, directly to space.
So how then does it turn out that the
ocean has a 1 mm
cooler layer at the top above the
ocean bulk and below the
skin?
Since the part of the atmosphere exchanging photons with the surface of the
ocean is generally
cooler than the surface (you model handles this poorly), LWR is a net loser for the
skin layer even before evaporation and conduction are considered.
So long as the
skin remains
cooler than the
ocean below it (the hook shape you refer to), the absorbed DLR wont directly heat the mixed
layer / bulk
ocean (same diff).
Otherwise that 1 mm
layer below the
skin which is 0.3 C
cooler than the
ocean bulk can not exist, yet it does.
For this reason, the
skin layer of the
ocean is almost always
cooler, not hotter, than
ocean a few cm below.
As long as we are confident that the
skin layer of the
ocean is
cooler than the water below — from observation or estimated energy flux — we know that excess DLR will reduce the energy flux from below.
This
layer is referred to as the molecular sub-
layer, the
skin layer or the
cool skin of the
ocean.
The emissivity and absorptivity of the
ocean are set to 1, there are no
ocean currents, the atmosphere doesn't heat up and
cool down with the
ocean surface, the solar radiation value doesn't change through the year, the top
layer was 5 mm not 1μm, the
cooler skin layer was not modeled, a number of isothermal
layers is unphysical compared with the real
ocean of continuously varying temperatures..
SW: So how then does it turn out that the
ocean has a 1 mm
cooler layer at the top above the
ocean bulk and below the
skin?
Yet it is the temperature of that
layer that the sensors interpret as a surface warming notwithstanding the further
cooling of the
ocean skin below it.
f) all the additional energy coming from the increase of the back radiation is thermalized within the
skin layer and then emitted back to the air by increasing radiation, convection, conduction and evaporation into the air so that none part of it is delivered to the
ocean — otherwise it would give us the decrease of the
cooling of the bulk temperature of the
ocean;
It can not do so because the 1 mm deep
layer above the
ocean bulk and 0.3 C
cooler than the
ocean bulk below (the subskin) effectively insulates the
skin layer from the
ocean bulk.
At night, convection brings as much energy to the surface of the
ocean as needed to prevent an unstable temperature gradient from forming, so evaporation doesn't
cool the
skin layer of the
ocean (without
cooling the bulk).
In terms of upward energy flow the
cooler interacting
layer pulls energy upward exactly as much as the warmer
skin slows it down for a zero net effect on the upward rate of flow from the
ocean.
Hartmut Grassl, (1976), The dependence of the measured
cool skin of the
ocean on wind stress and total heat flux, Boundary
Layer Meteorology
In a sense, the
ocean is heated from below the
skin layer by SWR and
cooled from the
skin layer by net LWR and evaporation.
Increased DLR - > warming of the knudsen (or evaporation)
layer - > evaporation that takes more energy than the DLR provides - > flux of energy upwards from
skin layer and below - >
cooling of the bulk
ocean.
This is due to the slowing down of the
cooling of the
ocean skin layer due to the reduction of the net flow of heat by radiation.
The
cool skin is recognized as an important feature of the
ocean viscous
layer as a result of new satellite remote sensing methodologies emerging for air - sea fluxes estimates [Chou et al., 2003].
The ocrean bulk probably does not change at all because the deepening and / or
cooling of the 1 mm
ocean skin layer restores the equilibrium between
ocean bulk and
ocean skin.
Yet the
skin layer does show warming and the sub
skin is
cooler than the
ocean bulk Observations rule and as we have seen already the science on these issues is vague and inconclusive so I wouldn't use the term «impossible».
3) That energy can only get from the
ocean to the atmosphere (and then to space) when the
skin layer is
cooler than the water immediately below.
The addition of water vapor and CO2 to the air
layer will reduce somewhat the total net flow, which means that the
cooling of the
ocean skin layer will be slightly slower.
CO2 doesn't heat the
ocean itself, it prevents
cooling with higher and higher concentrations via changing the temperature gradient of the
skin layer.
R Gates - There are two aspects to
ocean warming; increased greenhouse gas content of the atmosphere warms the
cool -
skin layer of the
ocean and lowers the thermal gradient through that
layer.
I'm willing to say that happens in some circumstances such as when the air above the water is saturated and also when breaking waves destroy the
cool skin layer but these are exceptions to the rule — RH is seldom 100 % over the
ocean and the
cool skin layer only breaks up in whitewater and reforms in about 10 seconds.
arncliffe - the thin
cool -
skin layer of the
ocean already is an insulating barrier.
My post on the
cool -
skin layer of the
ocean hyper - links to 3 different papers on the topic, and those three papers cites numerous others in support of the physics, math, and observations involved.
Instead of a decline in
ocean heat content, we have seen a dramatic increase - as the greenhouse gas - forcing of the
ocean's
cool -
skin layer predicts.
In simple terms it seems that the effect of downwelling LR radiation is not to heat the
ocean directly, but to turn the thin
cool skin layer into a thermal insulating barrier and thus increase OHC by reducing heat transmission to the atmosphere.