The upper 3 meters of the world's oceans hold more heat than the entire atmosphere, so continual ventilation of just 10 meters
of warmer subsurface water will affect the global average for decades.
Intruding water maintains a thick layer
of warmer subsurface water several hundred meters thick.
Where things get a little mysterious is in the attribution
of the warming subsurface to a change in the NA gyre circulation, which is attributed to a switch in the NAO (North Atlantic Oscillation) from a positive to a negative phase.
Not exact matches
That remote winds on the opposite side
of Antarctica can cause such a substantial
subsurface warming is a worrying aspect
of the circulation at the Antarctic margin.»
The planets
of the TRAPPIST - 1 system could be complex worlds with volcanoes, atmospheres and
warm subsurface oceans.
The basal melting due to
subsurface warming represents an important component
of the current ice mass loss,» Ezat points out.
They based it on a
subsurface plume
of warm water, called a Kelvin wave, surging from west to east across the tropical Pacific.
The moon's south pole has strange,
warm fractures, and plumes
of liquid water from a
subsurface ocean many believed was impossible in such a small, cold world.
«The main result supports and extends earlier work, showing that human forcing contributes to changing winds that contribute to
subsurface ocean
warming, affecting some grounding zones
of the ice sheet,» Alley said.
The search for this
subsurface ocean
warmed up after scientists discovered plumes
of mineral - rich water vapor squirting out
of cracks near the south pole.
Closer investigation
of these plumes, originating from geysers blasting from polar fissures in Enceladus» icy crust, revealed this water was coming from a
warm subsurface salty ocean and the water was laced with hydrocarbons and ammonia, or «many
of the ingredients that life would need if it were to start in an environment like that,» Soderblom tells HowStuffWorks.
These episodes occurred toward the end
of a period
of hundreds
of millions
of years during which
warm water interacted with
subsurface rocks.
«Our interpretation is a shift from thinking that the
warm, wet environment was mostly at the surface to thinking it was mostly in the
subsurface, with limited exceptions,» said Scott Murchie
of Johns Hopkins University Applied Physics Laboratory in Laurel, Md., a co-author
of the report and principal investigator for CRISM.
There are fears that Arctic
warming will worsen wildfires that, in turn, burn through
subsurface layers
of soil and hasten the thawing
of permafrost beneath.
In the 3D simulations we find similar
warming of the
subsurface layers as in the 1D simulations (Figure 6).
Highly cited Holland et al 2008 (Acceleration
of Jakobshavn Isbræ triggered by
warm subsurface ocean waters) uses 20 year grided dataset
of subsurf ocean T from commercial fishing industry.
That suggests
warm Arctic air temperatures is largely due to ventilation
of the abundant
subsurface heat that resides between 100 and 900 meters below the surface.
... a pronounced strengthening in Pacific trade winds over the past two decades — unprecedented in observations / reanalysis data and not captured by climate models — is sufficient to account for the cooling
of the tropical Pacific and a substantial slowdown in surface
warming through increased
subsurface ocean heat uptake.
In contrast to the surface
warming trend
of the Indian Ocean, Alory et al. (2007) found a
subsurface cooling trend
of the main thermocline over the Indonesian Throughflow region, that is, near EEIO, in 1960 — 99, the interval using the new Indian Ocean Thermal Archive.
Abstract:... Here we show that a pronounced strengthening in Pacific trade winds over the past two decades — unprecedented in observations / reanalysis data and not captured by climate models — is sufficient to account for the cooling
of the tropical Pacific and a substantial slowdown in surface
warming through increased
subsurface ocean heat uptake.
Combine with Co2
warming the surface and it can just so happen that the two effects cancel at the surface for a «pause» while the wind / current driven heating
of the
subsurface causes extra heating in the
subsurface.
Given this, it is quite clear that any reduction in the efficiency
of upward radiation (by, say, reflecting it right back down again), will have to be compensated for by increasing the air / sea (skin) temperature difference, hence having a
warmer subsurface temperature.
s the
subsurface warms, the top
of the gas hydrate stability zone will move downward.
I suppose that for a 3,7 W / m2 forcing, the additional energy
of forcing + feedbacks is used for faster processes (melting ice, evaporation,
warming of subsurface oceanic layers, etc.) and the new equilibrium is reach on a quite short timescale.
And what happens to all
of the
subsurface warm water that had shifted east during the El Niño and had remained below the surface.
Yan, X-H., H. Su, and W. Zhang, 2014: Contribution
of global
subsurface and deeper ocean
warming to recent global surface
warming hiatus.
New research shows how easterly winds in the summer
of 2014 caused the anomalously
warm subsurface water
of the tropical Pacific — which presages an El Niño event and formed following the early 2014 westerly wind burst — to never discharge poleward, thereby remaining in the tropical Pacific and giving a head start to the developing 2015 - 16 El Niño.
dana1981 - An additional part
of that correction is that the deeper
subsurface Antarctic waters are (relatively)
warmer than surface waters, not colder as stated in the OP.
While many sources
of stress have caused corals to bleach, «mass» coral bleaching (at scales
of 100 km or more) has only occurred when anomalously
warm ocean temperatures, typically coupled with high
subsurface light levels, exceeded corals» physiological tolerances.
The
warm water and calm winds
of this periodic Pacific tropical condition are «a big way to get
subsurface heat back to the surface.»
Wang & Zhang (2013, http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-12-00721.1): «Both observations and most
of the phase 5
of the Coupled Model Intercomparison Project (CMIP5) models also show that the
warm (cold) phase
of the AMO is associated with a surface
warming (cooling) and a
subsurface cooling (
warming) in the tropical North Atlantic (TNA).
It is further shown that the
warm phase
of the AMO corresponds to a strengthening
of the Atlantic meridional overturning circulation (AMOC) and a weakening
of the Atlantic subtropical cell (STC), which both induce an anomalous northward current in the TNA
subsurface ocean.
«The authors write that «the El Niño - Southern Oscillation (ENSO) is a naturally occurring fluctuation,» whereby «on a timescale
of two to seven years, the eastern equatorial Pacific climate varies between anomalously cold (La Niña) and
warm (El Niño) conditions,» and that «these swings in temperature are accompanied by changes in the structure
of the
subsurface ocean, variability in the strength
of the equatorial easterly trade winds, shifts in the position
of atmospheric convection, and global teleconnection patterns associated with these changes that lead to variations in rainfall and weather patterns in many parts
of the world,» which end up affecting «ecosystems, agriculture, freshwater supplies, hurricanes and other severe weather events worldwide.»»
Because the mean meridional temperature gradient
of the
subsurface ocean is positive because
of the temperature dome around 9 ° N, the advection by the anomalous northward current cools the TNA
subsurface ocean during the
warm phase
of the AMO.
The temperature
of the water below the surface remained above - average, as the large area
of warmer - than - average
subsurface waters continued to move slowly to the east (a downwelling Kelvin wave).
In fact simultaneously with the strengthening
warming of the
subsurface western Pacific is an intensification
of the cold
subsurface tongue at the east Pacific (WUWT ENSO page).
report that ocean sediment cores containing an «undisturbed history
of the past» have been analyzed for variations in PP over timescales that include the Little Ice Age... they determined that during the LIA the ocean off Peru had «low PP, diatoms and fish,» but that «at the end
of the LIA, this condition changed abruptly to the low
subsurface oxygen, eutrophic upwelling ecosystem that today produces more fish than any region
of the world's oceans... write that «in coastal environments, PP, diatoms and fish and their associated predators are predicted to decrease and the microbial food web to increase under global
warming scenarios,» citing Ito et al..
Then, as the La Nina
of 1998/99/00 / 01 progressed, the trade winds, Pacific Equatorial Currents, and a phenomenon known as a Rossby wave returned the remaining surface and
subsurface warm water to the western Pacific.
The layer
of warm surface water that was blown west is then replaced by cooler water from the
subsurface, cooling the entire tropical Pacific.
The strong
warming of the
subsurface ocean is a testament to this.
Localized rapid
warming of West Antarctic
subsurface waters by remote winds (Nature Climate Change)
Warming of surface ocean waters is well known, but how the
subsurface waters are changing is less clear.
Based on a conceptual oceanographic model, the researchers propose a mechanism for the
subsurface warming of the glacial Arctic Ocean: A reduced influx
of freshwater to the Arctic Ocean acted to deepen the halocline and push the
warm Atlantic Layer downward.
The new study published as a Letter in Nature Geoscience shows that the
warm intermediate Atlantic Layer was displaced far downward in the glacial Arctic Ocean, resulting in a substantial
warming at depths between 1000 and 2500 m. Based on a conceptual oceanographic model, the researchers propose a mechanism for the
subsurface warming of the glacial Arctic Ocean: A reduced influx
of freshwater to the Arctic Ocean acted to deepen the halocline and push the
warm Atlantic Layer downward.
The study found that the Pacific Ocean is the main source
of the
subsurface warm water but some
of these waters have already been pushed to the Indian Ocean.
«If the southern ocean forcing (
subsurface warming)
of the Antarctic ice sheets continues to grow, it likely will become impossible to avoid sea level rise
of several meters, with the largest uncertainty being how rapidly it will occur,» the report states.
Reduced equatorial cloud cover during La Nina (due to the cooler sea surface temperature), combined with the strong upwelling (Ekman suction) in the eastern equatorial Pacific, does indeed lead to greater
warming of the ocean - because it's bringing cool
subsurface water to the surface, where it can be heated by the sun.
Seriously though, considering our lack
of measurement continuity it is conceivable (if not entirely believable) that energy from the sun that heated a surface that then emitted IR that would have been radiated to space but instead was absorbed because
of the slight increase in bandwidth coverage that a few extra CO2 molecules have provided and then emitted to Earth has been transferred through the sea surface unnoticed (cough, cough) and
warmed subsurface layers.
... then why do the vertical mean temperature anomalies (NODC 0 - 2000 meter data)
of the Pacific Ocean as a whole and
of the North Atlantic fail to show any
warming over the past decade, a period when ARGO floats have measured
subsurface temperatures, providing reasonably complete coverage
of the global oceans?
Based on discussions with my colleagues Rong Zhang and Mike Winton, this seems to be a consequence
of an AMOC (Atlantic Meridional Overturning Circulation) which builds in strength when the aerosol cooling is strong, trying to balance a part
of the cooling at the surface with
warm waters advected in from the tropics, but also — by a process that is not particularly straightforward — cools the
subsurface waters.