A new method for diagnosing radiative forcing and climate sensitivity

  title={A new method for diagnosing radiative forcing and climate sensitivity},
  author={Jonathan M. Gregory and William Ingram and Michael A. Palmer and Gareth S. Jones and Peter Stott and Robert B. Thorpe and Jason A. Lowe and Timothy C. Johns and K D Williams},
  journal={Geophysical Research Letters},
[1] We describe a new method for evaluating the radiative forcing, the climate feedback parameter (W m−2 K−1) and hence the effective climate sensitivity from any GCM experiment in which the climate is responding to a constant forcing. The method is simply to regress the top of atmosphere radiative flux against the global average surface air temperature change. This method does not require special integrations or off-line estimates, such as for stratospheric adjustment, to obtain the forcing… Expand

Figures and Tables from this paper

Climate Forcings and Climate Sensitivities Diagnosed from Coupled Climate Model Integrations
A simple technique is proposed for calculating global mean climate forcing from transient integrations of coupled atmosphere–ocean general circulation models (AOGCMs). This “climate forcing” differsExpand
Using an AGCM to Diagnose Historical Effective Radiative Forcing and Mechanisms of Recent Decadal Climate Change
AbstractAn atmospheric general circulation model is forced with observed monthly sea surface temperature and sea ice boundary conditions, as well as forcing agents that vary in time, for the periodExpand
Tropospheric Adjustment Induces a Cloud Component in CO2 Forcing
Abstract The radiative forcing of CO2 and the climate feedback parameter are evaluated in several climate models with slab oceans by regressing the annual-mean global-mean top-of-atmosphere radiativeExpand
The Climate Sensitivity and Its Components Diagnosed from Earth Radiation Budget Data
One of the major uncertainties in the ability to predict future climate change, and hence its impacts, is the lack of knowledge of the earth’s climate sensitivity. Here, data are combined from theExpand
An assessment of methods for computing radiative forcing in climate models
Because the radiative forcing is rarely computed separately when performing climate model simulations, several alternative methods have been developed to estimate both the instantaneous (or direct)Expand
A Temporal Kernel Method to Compute Effective Radiative Forcing in CMIP5 Transient Simulations
AbstractEffective radiative forcing (ERF) is calculated as the flux change at the top of the atmosphere after allowing rapid adjustments resulting from a forcing agent, such as greenhouse gases.Expand
Radiative flux and forcing parameterization error in aerosol‐free clear skies
A dependence on atmospheric conditions, including integrated water vapor, means that global estimates of parameterization error relevant for the radiative forcing of climate change will require much more ambitious calculations. Expand
Constraining climate sensitivity with linear fits to outgoing radiation
[1] Several papers have used correlations between outgoing radiation and surface temperature to estimate climate sensitivity via a linearized energy balance equation. A crucial assumption in suchExpand
Re-Examining the First Climate Models: Climate Sensitivity of a Modern Radiative–Convective Equilibrium Model
We revisit clear-sky one-dimensional radiative–convective equilibrium (1D-RCE) and determine its equilibrium climate sensitivity to a CO2 doubling (ECS) and associated uncertainty. Our 1D-RCEExpand
Multiannual Ocean–Atmosphere Adjustments to Radiative Forcing
AbstractIn radiative forcing and climate feedback frameworks, the initial stratospheric and tropospheric adjustments to a forcing agent can be treated as part of the forcing and not as a feedback, asExpand


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
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
The time-dependence of climate sensitivity
A doubled CO2 coupled ocean-atmosphere experiment has been run for over 800 years. The ‘effective’ equilibrium climate sensitivity to a doubling of CO2 (the equilibrium response of the model assumingExpand
Transient Climate Change in the Hadley Centre Models: The Role of Physical Processes
Abstract A comparison of the response to increasing greenhouse gas concentrations of two versions of the Met Office's (Hadley Centre) coupled atmosphere–ocean model reveals differences that result inExpand
The simulation of SST, sea ice extents and ocean heat transports in a version of the Hadley Centre coupled model without flux adjustments
Abstract Results are presented from a new version of the Hadley Centre coupled model (HadCM3) that does not require flux adjustments to prevent large climate drifts in the simulation. The model hasExpand
Long-term climate changes due to increased CO2 concentration in the coupled atmosphere-ocean general circulation model ECHAM3/LSG
Abstract The long-term adjustment processes of atmosphere and ocean in response to gradually increased atmospheric CO2 concentration have been analysed in two 850-year integrations with a coupledExpand
Reconstruction of solar irradiance since 1610: Implications for climate change
Solar total and ultraviolet (UV) irradiances are reconstructed annually from 1610 to the present. This epoch includes the Maunder Minimum of anomalously low solar activity (circa 1645-1715) and theExpand