From the formula, we can see that the carbon footprint area is essentially calculated by dividing total anthropogenic carbon emissions remaining after accounting
for ocean uptake (i.e., 72 % of net human emissions) by the rate at which existing forests sequester carbon.
The 40 - 50 % range
for the ocean uptake refers to the fast uptake, which occurs mainly in few years or very rapidly in relation to the increase in the atmospheric concentration.
Not exact matches
«Copepod migrations are important
for the
ocean's CO2
uptake.»
The model also accounted
for natural drivers of change, including the direct influence of increased carbon dioxide on
ocean - carbon
uptake and the indirect effect that a changing climate has on the physical state of the
ocean and its relationship to atmospheric carbon dioxide.
For the change in annual mean surface air temperature in the various cases, the model experiments show the familiar pattern documented in the SAR with a maximum warming in the high latitudes of the Northern Hemisphere and a minimum in the Southern
Ocean (due to ocean heat uptak
Ocean (due to
ocean heat uptak
ocean heat
uptake)(2)
For one thing, the fit neglects lags in the system (such as those resulting from
ocean heat
uptake) and it also neglects changes in albedo and other radiative factors.
«We have to consider there are two sides of the coin: On the one hand, the
uptake of carbon dioxide moderates climate change but, on the other hand, it affects life in the
ocean — with consequences
for economy and society.»
Dr Peter Stott, commenting on Gavin's study in the Guardian, http://www.theguardian.com/environment/2015/jun/04/global-warming-hasnt-paused-study-finds says the term slowdown is valid because the past 15 years might have been still hotter were it not
for natural variations like deep
ocean heat
uptake.
The treatment of uncertainty in the
ocean's
uptake of heat varies, from assuming a fixed value
for a model's
ocean diffusivity (Andronova and Schlesinger, 2001) to trying to allow
for a wide range of
ocean mixing parameters (Knutti et al., 2002, 2003) or systematically varying the
ocean's effective diffusivity (e.g., Forest et al., 2002, 2006; Frame et al., 2005).
Further, it suggests a clear mechanism
for the «efficacies» of both
ocean heat
uptake and radiative forcing.»
The upper 95th percentile is not well constrained, particularly in studies that account conservatively
for uncertainty in,
for example, 20th - century radiative forcing and
ocean heat
uptake.
«Warming of the
oceans and increased
uptake of CO2 is of increasing concern
for the marine environment.
If I instantly quadruple CO2 in an experiment, I'd expect
ocean heat
uptake (OHU) to occur pretty uniformly in latitude
for the initial few years, but then become pretty localized to the subpolar
oceans after, say, year 100.
The authors note that more than 85 % of the global heat
uptake (Q) has gone into the
oceans, including increasing the heat content of the deeper
oceans, although their model only accounts
for the upper 700 meters.
Includes the company's proprietary natural
Ocean Kelp Formula, OptiLife3TM, which provides three key natural benefits
for pets: antioxidants to reduce the effects of normal environmental stress and to support a healthy immune system and prebiotics to promote nutrient
uptake and digestion.
His description should be read
for details, but the essence of the evidence lies in the observation that
ocean heat
uptake (OHC) has been increasing during the post-1950 warming.
[Response: I'm sure Eric won't mind me stepping in with some questions
for you instead — 1) why do you keep insinuating that terrestrial and
ocean uptake of anthropogenic CO2 is somehow not accepted by mainstream scientists?
Since OHC
uptake efficiency associated with surface warming is low compared with the rate of radiative restoring (increase in energy loss to space as specified by the climate feedback parameter), an important internal contribution must lead to a loss rather than a gain of
ocean heat; thus the observation of OHC increase requires a dominant role
for external forcing.
Dr Peter Stott, commenting on Gavin's study in the Guardian, http://www.theguardian.com/environment/2015/jun/04/global-warming-hasnt-paused-study-finds says the term slowdown is valid because the past 15 years might have been still hotter were it not
for natural variations like deep
ocean heat
uptake.
The estimated
uptake timescales are within the range he reports
for his data - driven calculation, 50 years or so, even though the mean
uptake time of the
ocean reservoirs in that model, weighted by their sizes, is 600 years.
Your attempt to estimate equilibrium climate sensitivity from the 20th C won't work because a) the forcings are not that well known (so the error in your estimate is large), b) the climate is not in equilibrium — you need to account
for the
uptake of heat in the
ocean at least.
Furthermore, the data shown in the same source show that
ocean CO2
uptake as a percentage
for the period 1980 - 1999 appears to be decreasing.
It is found that a radiative forcing from non-CO2 gases of approximately 0.6 W m -LRB--2) results in a near balance of CO2 emissions from the terrestrial biosphere and
uptake of CO2 by the
oceans, resulting in near - constant atmospheric CO2 concentrations
for at least a century after emissions are eliminated.»
... 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 these experiments the climate sensitivity was 2.7 deg C
for a doubling of CO2, the net aerosol forcing from 1940 to 2000 was around -0.7 W / m2 (55 % of the total forcing, -1.27, from 1850 to 2000), and the
ocean uptake of heat was well - matched to recent observations.
Further, it suggests a clear mechanism
for the «efficacies» of both
ocean heat
uptake and radiative forcing.»
The problems with Jacobson's calculation are (1) the assumption that the atmospheric pCO2 is relaxing toward preanthropogenic in Jacobson's equation 1, and (2) the wide range of
uptake time scales
for different parts of the
ocean, which interact with the accelerated rise in atmospheric pCO2.
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.
If one was to redo those papers, you would choose the efficacies most relevant to their calculations (i.e. the ERF derived values
for Otto et al) along with their adjustment
for the
ocean heat
uptake (in our sensitivity test), and conclude that instead of an ECS of 2.0 ºC [likely range 1.4 - 3.2], you'd get 3.0 ºC [likely range 1.8 - 6.2].
If I instantly quadruple CO2 in an experiment, I'd expect
ocean heat
uptake (OHU) to occur pretty uniformly in latitude
for the initial few years, but then become pretty localized to the subpolar
oceans after, say, year 100.
Indeed, Jim Hansen used such a diffusive mixing
for representing
ocean heat
uptake in several of his seminal papers.
But, we have explanation
for the «pause» ranging from reduction in solar activity, increase
ocean uptake, CFC curtailment and Chinese aerosol.
For example: 1) plants giving off net CO2 in hot conditions (r / t aborbing)-- see: http://www.climateark.org/articles/reader.asp?linkid=46488 2) plants dying out due to heat & drought & wild fires enhanced by GW (reducing or cutting short their
uptake of CO2 & releasing CO2 in the process) 3)
ocean methane clathrates melting, giving off methane 4) permafrost melting & giving off methane & CO2 5) ice & snow melting, uncovering dark surfaces that absorb more heat 6) the warming slowing the thermohaline
ocean conveyor & its up - churning of nutrients — reducing marine plant life & that carbon sink.
Then when they have partitioned themselves according to the original distribution, we will still have 15 % of the green molecules in the atmosphere, and these will only disappear over the longer time that it takes
for mixing with the deep
ocean and permanent
uptake in the terrestrial sink, possibly more than 1000 years.
For example, there are not sufficient observations of the
uptake of heat, particularly into the deep
ocean, that would be one of the possible mechanisms to explain this warming hiatus.»
For example, with some species of coccolithophores increasing in abundance at the expense of others, the
ocean ecosystem might shift towards species that carry more carbon away from the surface and into the
ocean interior, causing greater
uptake of carbon into the
oceans (See Langer et al., 2007).
Model simulations
for the North Atlantic
Ocean and thermodynamic principles reveal that this feedback should be stronger, at present, in colder midlatitude and subpolar waters because of the lower present - day buffer capacity and elevated DIC levels driven either by northward advected surface water and / or excess local air - sea CO2
uptake.
Cumulative land and
ocean uptake of carbon
for the period 1850 - 2005.
The graphs on the right show the mean carbon
uptake by land and
ocean for each latitude line corresponding with the adjacent maps.
What model have you assumed
for the rate of the
oceans» heat
uptake?
At constant salinity net O2 evolution never exceeded 0.5 mol l - 1 h - 1 while net CO2
uptake consistently averaged 3 mol l - 1 h - 1
for an apparent net production of 36 mg C m - 3 h - 1, which greatly exceeds the O2 changes and open
ocean 14C estimates from the literature.
Section 8.6 discusses the various feedbacks that operate in the atmosphere - land surface - sea ice system to determine climate sensitivity, and Section 8.3.2 discusses some processes that are important
for ocean heat
uptake (and hence transient climate response).
The coralline sponges also indicate that your formula doesn't hold
for the period after 1940, as increased plant
uptake + increased deep
ocean release of CO2 (the only other fast source of huge quantities of CO2) both should increase the d13C level of the atmosphere and the upper
ocean waters.
These scaling factors compensate
for under - or overestimates of the amplitude of the model response to forcing that may result from factors such as errors in the model's climate sensitivity,
ocean heat
uptake efficiency or errors in the imposed external forcing.
The same holds
for human CO2 releases: an initial increase in atmospheric CO2 levels will lead to increased
uptake by the
oceans and biosphere, but a part of the increase will remain in the atmosphere, as long as CO2 is constantly added.
Ocean warming: «Assessing recent warming using instrumentally homogeneous sea surface temperature records» «Tracking ocean heat uptake during the surface warming hiatus» «A review of global ocean temperature observations: Implications for ocean heat content estimates and climate change» «Unabated planetary warming and its ocean structure since 2006&r
Ocean warming: «Assessing recent warming using instrumentally homogeneous sea surface temperature records» «Tracking
ocean heat uptake during the surface warming hiatus» «A review of global ocean temperature observations: Implications for ocean heat content estimates and climate change» «Unabated planetary warming and its ocean structure since 2006&r
ocean heat
uptake during the surface warming hiatus» «A review of global
ocean temperature observations: Implications for ocean heat content estimates and climate change» «Unabated planetary warming and its ocean structure since 2006&r
ocean temperature observations: Implications
for ocean heat content estimates and climate change» «Unabated planetary warming and its ocean structure since 2006&r
ocean heat content estimates and climate change» «Unabated planetary warming and its
ocean structure since 2006&r
ocean structure since 2006»
Chance that increased GHGs are expected to lead to warming on the scale of the observed warming: this requires estimates of climate sensitivity,
ocean heat
uptake, etc., but I would think that basic theory suggests that increased GHGs could be responsible
for much more than the observed warming.
fanciful — has it ever been proposed that
ocean heat
uptake during interglacials might be the planets way of preparing
for the next ice age, when the
oceans give up the heat to preserve continuity of life on the surface — I know, sounds a bit link an intelligent Gaia mythology, but doesn't the notion of synergy suggest the possibility?
Thus the
oceans are a little stronger in CO2 release
for increased temperature than that vegetation is in more
uptake.
The cycle of extra heat
uptake by the
oceans may be over
for at least a decade.