Video: Dr. Kevin Trenberth explains
general climate sensitivity on Earth.
The United Nations» Intergovernmental Panel on Climate Change, a global effort involving hundreds of climate scientists and the governments of 100 nations, projected in 2001 that, depending on the rate of greenhouse gas emissions and
general climate sensitivities, the global average temperature would rise 2.5 to 10.4 degrees Fahrenheit between 1990 and 2100.
Not exact matches
Thus in summary, a change in
sensitivity of one of the primary actors in
climate variation has only effect for the
general sensitivity of
climate, if all the feedbacks are essentially similar for all primary actors involved, which is highly probably not the case...
Hourdin, F., et al., 2006: The LMDZ4
general circulation model:
Climate performance and
sensitivity to parameterized physics with emphasis on tropical convection.
We look to the real world and the paleo record to constrain those aspects of the
climate system that have non-negligible uncertainties (most often
climate sensitivities in a
general sense).
(in
general, whether for future projections or historical reconstructions or estimates of
climate sensitivity, I tend to be sympathetic to arguments of more rather than less uncertainty because I feel like in
general, models and statistical approaches are not exhaustive and it is «plausible» that additional factors could lead to either higher or lower estimates than seen with a single approach.
If Judge Alsup needs further just cause for being fed up with Watts Up, Judge Judy's latest
climate sensitivity ruling in concord with Obfuscator
General Lewis may provide it.
Thus in summary, a change in
sensitivity of one of the primary actors in
climate variation has only effect for the
general sensitivity of
climate, if all the feedbacks are essentially similar for all primary actors involved, which is highly probably not the case...
If
climate sensitivity is higher than thought as so much evidence keeps suggesting recently, when do actually take this seriously and just stop using fossil fuels on a personal and
general level?
Steve McIntyre's failed
sensitivity analysis has been used by a much wider audience to dispute the Yamal hockey stick, accuse scientists of fraud and undermine the credibility of
climate science in
general.
Given that our best bet of
climate sensitivity has remained the same (1.5 — 4.5 C) for over 30 years with all new information «pretty much cancelling out», at one point do we begin to focus this investment more on mitigation or another approaches to
climate change in
general?
The
general picture is that current policy would have to work as intended (not a guarantee in the United States or internationally) and
climate sensitivity would have to be very low to prevent exceeding the international target of 2 °C (let alone, 1.5 °C, which will be a policy and technological challenge even in a low -
sensitivity world).
That would be the
General Fluid Dynamics Laboratory which produced the lower «
climate sensitivity» range, (Manabe) which was «averaged» with the much higher GISS estimate to produce a high end estimate that was assumed to be real science, when it was actually an average of WAGs.
This is computer model crap based on
General Circulation Models that fails to predict anything and the
climate sensitivity is feeded in the model even though they do nt have a clue what it is.
Climate sensitivity is defined in a
general way.
«Seasonal Cycle Experiments on
Climate Sensitivity Due to a Doubling of CO2 with an Atmospheric
General Circulation Model Coupled to a Simple Mixed Layer Ocean Model.»
«The
Sensitivity of Monsoon
Climates to Orbital Parameterization Changes for 9000 Years BP: Experiments with the NCAR
General Circulation Model.»
«
Climate Sensitivity Due to Increased CO2: Experiments with a Coupled Atmosphere and Ocean
General Circulation Model.»
In
general, diversity shifts towards the coast and northwards, and the degree depends on the dispersal assumptions, emission scenarios, and the
sensitivity of
climate simulations.
Within this
general definition, several specific forms of
climate sensitivity exist that differ in terms of the types of
climate feedbacks they include.
The three successive IPCC reports (1991 [2], 1996, and 2001 [3]-RRB- concentrated therefore, in addition to estimates of equilibrium
sensitivity, on estimates of
climate change over the 21st century, based on several scenarios of CO2 increase over this time interval, and using up to 18
general circulation models (GCMs) in the fourth IPCC Assessment Report (AR4)[4].
Computer simulations of the
climate, referred to as «
general circulation models» (GCMs), can be used to assess the
sensitivity of
climate to changes that might result from increased greenhouse gases.
Beyond the specific issue of
climate sensitivity, it raises the more
general problem of optimal model complexity.
A
general agreement that IF this trend continues for another «X» years despite continued increase of GHG concentrations, there will be enough evidence in the red column to seriously question the ability of the GCMs cited by IPCC: a) to correctly assess human attribution of past
climate change b) to estimate
climate sensitivity c) to make meaningful projections of future
climate changes due to AGW
Due to computational constraints, the equilibrium
climate sensitivity in a
climate model is usually estimated by running an atmospheric
general circulation model coupled to a mixed - layer ocean model, because equilibrium
climate sensitivity is largely determined by atmospheric processes.
Pfeiffer, M. & Lohmann, G. Greenland ice sheet influence on last interglacial
climate: global
sensitivity studies performed with an atmosphere — ocean
general circulation model.
So many estimations of
climate sensitivity have now been made, involving many different methods and eras, that I have the sense that our confidence in the
general range of values that has emerged is reinforced by the convergence of data.
Nevertheless, in
general, Annan's comments are consistent with the body of mainstream
climate science research, and most of his colleagues believe that
climate sensitivity is most likely close to 3 °C surface warming in response to doubled CO2; unlikely to be more than 4.5 °C or less than 2 °C.
What counts here is it looks like the warming has been significantly over-estimated, Paper after paper is coming out with the same
general conclusion, that
climate sensitivity is looking much less dire.
Since
climate models in
general screw the «
sensitivity» estimating pooch and the absolute temperature, it should be pretty obvious who should never have been involved in the debate.
IF temperatures rise by < 2 C, as appears centrally likely based on current re-estimates of
climate sensitivity using improved analysis of aerosols and taking into account the pause and the
general lack of tropospheric warming, then it is more likely to be more expensive to mitigate.
13.2.1 Incremental Scenarios for
Sensitivity Studies 13.2.2 Analogue Scenarios 13.2.2.1 Spatial analogues 13.2.2.2 Temporal analogues 13.2.3 Scenarios Based on Outputs from
Climate Models 13.2.3.1 Scenarios from General Circulation Models 13.2.3.2 Scenarios from simple climate models 13.2.4 Other Types of Sc
Climate Models 13.2.3.1 Scenarios from
General Circulation Models 13.2.3.2 Scenarios from simple
climate models 13.2.4 Other Types of Sc
climate models 13.2.4 Other Types of Scenarios
And, in
general, cloud changes caused by internal
climate dynamics seem much more likely to lead to the Forster / Gregory 06 method over-estimating
sensitivity than under - estimating it, as pointed out in the article.
My main interest is in understanding what, if anything, we can say about
climate sensitivity that does not rely on
General Circulation Models.
The
sensitivity of NPP to
climate change is especially uncertain because it depends on changing soil water availability, which varies significantly between
General Circulation Models (GCMs), with some models suggesting major drying and reduced productivity in tropical ecosystems (Cox et al., 2004).
Here is the skeptical side of Abelson at a time, almost 2o years ago, when
climate science in
general operated on a much smaller set of data (but note that he quotes more or less the same wide range of
climate sensitivity estimates that are the norm today)-- Abelson
The introduction to the debate gives a
general background on the various estimates for the equilibrium
climate sensitivity (ECS) and transient
climate response (TCR to a doubling of CO2 and asks these questions:
-LSB-...] «
Sensitivity training directly on the battlefield» sounds like something libs would do NOAA Misrepresents Inspector
General Report New report exonerates U.S.
climate researchers What would you expect from this -LSB-...]
Contrary to Schlesinger's result, the majority of state - of - the - art four - dimensional «
general circulation models» (GCMs)- the kind used in the Trenberth and Fasullo study - estimate the
climate sensitivity is closer to 3 degrees C.
Indeed, since in
general GCMs significantly overestimate aerosol forcing compared with observations, they need to embody a high
climate sensitivity or they would underestimate historical warming and be consigned to the scrapheap.
Nic Lewis in the post at BishopHill does a very nice empirically based
sensitivity analysis following the
general methodology of the Gregory et al (2002) heat balance change derived value of the equilibrium
climate sensitivity, determining a value of ECS of 1.6 - 1.7 C.
For this and other reasons, it is not possible to obtain
climate sensitivity numerically using
general - circulation models: for, as Akasofu (2008) has pointed out,
climate sensitivity must be an input to any such model, not an output from it.
Climate responds to many internal and external factors, and understanding how it varied 1000 years ago informs us about factors that might have operated then (and perhaps about climate sensitivity in general), but little about the current mix of f
Climate responds to many internal and external factors, and understanding how it varied 1000 years ago informs us about factors that might have operated then (and perhaps about
climate sensitivity in general), but little about the current mix of f
climate sensitivity in
general), but little about the current mix of factors.