Efficacy of climate forcings

  title={Efficacy of climate forcings},
  author={J. E. Hansen and Makiko Sato and Reto Ruedy and Larissa S. Nazarenko and Andrew A. Lacis and Gavin A. Schmidt and Gary L. Russell and Igor Aleinov and Mike Bauer and Susanne E Bauer and N. Bell and Brian Cairns and Vittorio Canuto and Mark A. Chandler and Y. Cheng and Anthony D. Del Genio and Gregory Faluvegi and Eric L. Fleming and Andrew D. Friend and Timothy M. Hall and Charles H. Jackman and Maxwell Kelley and Nancy Y. Kiang and Dorothy M. Koch and J. L. Lean and Jean Lerner and Ken K. Lo and Surabi Menon and Ronald Lindsay Miller and Patrick Minnis and Tica Novakov and V. Oinas and Jan P. Perlwitz and Judith Perlwitz and David Rind and Anastasia Romanou and Drew T. Shindell and Peter H. Stone and Shan Sun and N. L. Tausnev and D. Thresher and Bruce A. Wielicki and Takmeng Wong and M. S. Yao and S. Zhang},
  journal={Journal of Geophysical Research},
[1] We use a global climate model to compare the effectiveness of many climate forcing agents for producing climate change. We find a substantial range in the “efficacy” of different forcings, where the efficacy is the global temperature response per unit forcing relative to the response to CO2 forcing. Anthropogenic CH4 has efficacy ∼110%, which increases to ∼145% when its indirect effects on stratospheric H2O and tropospheric O3 are included, yielding an effective climate forcing of ∼0.8 W/m2… Expand
The impact of forcing efficacy on the equilibrium climate sensitivity
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There is no evidence for an efficacy effect on historical GSAT trend estimates based on simulations with an impulse response model, nor on the resulting estimates of climate sensitivity derived from the historical period. Expand
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Effective radiative forcing and adjustments in CMIP6 models
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[1] Observations and simulations (using the HadCM3 AOGCM) of time-dependent twentieth-century climate change indicate a linear relationship F = rDT between radiative forcing F and global mean surfaceExpand
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We present new calculations of radiative forcing at very high concentrations of CO2, CH4, and N2O, relevant to extreme anthropogenic climate change and paleoclimate studies. CO2 forcing is calculatedExpand
Effective radiative forcing and adjustments in CMIP6 models
The effective radiative forcing, which includes the instantaneous forcing plus adjustments from the atmosphere and surface, has emerged as the key metric of evaluating human and natural influence onExpand
LGM climate forcing and ocean dynamical feedback and their implications for estimating climate sensitivity
Abstract. Equilibrium climate sensitivity (ECS) has been directly estimated using reconstructions of past climates that are different than today’s. A challenge to this approach is that temperatureExpand
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Climate forcings in the industrial era.
Uncertainty in climate forcings have supplanted global climate sensitivity as the predominant issue for long-term climate projections: current trends in GHGClimate forcings are smaller than in popular "business as usual" or 1% per year CO2 growth scenarios. Expand
An alternative to radiative forcing for estimating the relative importance of climate change mechanisms
[1] Radiative forcing is widely used to measure the relative efficacy of climate change mechanisms. Earlier general circulation model (GCM) experiments showed that the global-mean radiative forcingExpand
Natural and anthropogenic climate change: incorporating historical land cover change, vegetation dynamics and the global carbon cycle
Abstract This study explores natural and anthropogenic influences on the climate system, with an emphasis on the biogeophysical and biogeochemical effects of historical land cover change. TheExpand
The missing climate forcing
Observed climate change is consistent with radiative forcings on several time-scales for which the dominant forcings are known, ranging from the few years after a large volcanic eruption toExpand
Climate forcings in Goddard Institute for Space Studies SI2000 simulations
[1] We define the radiative forcings used in climate simulations with the SI2000 version of the Goddard Institute for Space Studies (GISS) global climate model. These include temporal variations ofExpand
Radiative forcing and climate response
We examine the sensitivity of a climate model to a wide range of radiative forcings, including changes of solar irradiance, atmospheric CO2, O3, CFCs, clouds, aerosols, surface albedo, and a “ghost”Expand
A comparison of climate response to different radiative forcings in three general circulation models: towards an improved metric of climate change
Abstract. In order to review, and possibly refine, the concept of radiative forcing as a suitable metric for climate change, the responses of three general circulation models to distinct forcingExpand
Indirect Aerosol Forcing, Quasi Forcing, and Climate Response
Abstract The component of the indirect aerosol effect related to changes in precipitation efficiency (the second indirect or Albrecht effect) is presently evaluated in climate models by taking theExpand
Forcings and chaos in interannual to decadal climate change
We investigate the roles of climate forcings and chaos (unforced variability) in climate change via ensembles of climate simulations in which we add forcings one by one. The experiments suggest thatExpand
The 100 000-Yr Cycle in Tropical SST, Greenhouse Forcing, and Climate Sensitivity
  • D. Lea
  • Environmental Science
  • 2004
Abstract The key scientific uncertainty in the global warming debate is the equilibrium climate sensitivity. Coupled atmosphere–ocean general circulation models predict a wide range of equilibriumExpand