Verbose descriptions of ensembles experiments for the ensembles questionnaire #998
Hi Charlotte,
The ENSEMBLES decadal experiment we will document is the equivalent to
"Experiment 1.1 decadal ":
The text describing it should change to:
Ensemble of 10-year hindcasts and predictions. Assess model skill in
forecasting climate change on time-scales when the initial climate may
exert some influence.
The atmospheric composition (and other conditions) should be
prescribed using some estimate of the observed greenhouse gas and
anthropogenic aerosol concentrations and the A1B scenario from 2000.
Total solar irradiation variations should be prescribed too. No
observed volcanic aerosol load information should be used during the
hindcast, and only some sort of persistence of the load at the initial
date is allowed. Ocean initial conditions should be in some way
representative of the observed anomalies or full fields for the start
date. Land, sea-ice and atmosphere initial conditions are left to the
discretion of each group. Simulations should be initialized on the 1st
of November of 1960, 1965, 1970, 1975, 1980, 1985, 1990, 1995 and 2000
and 2005. A minimum ensemble size of 3 should be produced for each start date.
Note that some sentences have disappeared, such as the need to have
complete years, which implies running until the 31st of December of
the last year.
Among the requirements, I'd leave the following:
1.1.ic.oc InitialCondition
Ocean Initial Conditions must represent in some measure the observed anomalies for the start date used
1.1.bc.ant_wmg BoundaryCondition
Imposed changing concentrations of well mixed gases (anthropogenic)
1.1.bc.ant_aer BoundaryCondition
Imposed changing concentrations or emissions of aerosols (anthropogenic)
1.1.bc.solar BoundaryCondition
Imposed changing solar forcing
1.1.bc.!NoVolc2005 BoundaryCondition
No volcanic aerosol emissions beyond 2005
1.1.bc.seaice BoundaryCondition
Sea ice observations forcing (unless modelled) must precede start date of simulation
1.1.stc.decadal_10yr SpatioTemporalConstraint? Run for 10 years
Required Duration: !1960-09-01T00:00:00Z to !1970-10-31T23:59:59Z plus 10 years
Required Resolution: None
1.1.bc.a1b_wmg BoundaryCondition
Imposed changing concentrations or emissions of A1B well mixed gases, including CO2
1.1.bc.a1b_sls BoundaryCondition
Imposed changing concentrations or emissions of A1B short lived gas species
1.1.bc.a1b_aer BoundaryCondition
Imposed changing concentrations or emissions of A1B aerosols
---
Hi Charlotte,
following Paco's descriptions please find here the ensembles centennial descriptions and conformances aspects.
The ENSEMBLES centennial experiment we will document is very close to the - Experiment 3.2 historical: http://q.cmip5.ceda.ac.uk/cmip5/15/experiment/50/ - Experiment 4.1 rcp45: http://q.cmip5.ceda.ac.uk/cmip5/15/experiment/3/ - Experiment 4.3 rcp26: http://q.cmip5.ceda.ac.uk/cmip5/15/experiment/44/
If you have any questions do not hesitate.
Regards. Sébastien
Experiment 20C3M:
Simulation of recent past. Evaluate model performance against present climate and observed climate change. Simulation of recent past (1850 to 2000). Impose changing conditions (consistent with observations).
For the 1860 to 2000 (present day) period, the 20C3M (twentieth Century in Coupled Climate Models) model run specifies anthropogenic forcings (GHGs, aerosols as concentrations or precursor emissions, ozone, and land use change), in most cases without any variation in natural (solar and volcanic) forcings. Some additional 20C3M simulations were also conducted including solar and volcanic forcings as specified in previous AR4 simulations, to allow a better comparison with observed changes for validation purposes, and two models only ran 20C3M simulations with anthropogenic plus solar and volcanic forcing.
| 2.1.ic | InitialCondition? | Initial conditions are from experiment 3.1.piControl |
| 2.1.bc.ant_wmg_conc | BoundaryCondition? | Imposed changing concentrations of historical anthropogenic well mixed gases, including CO2 |
| 2.1.bc.volc_wmg_conc | BoundaryCondition? | Imposed changing concentrations of historical volcanic well mixed gases, including CO2 |
| 2.1.bc.sls | BoundaryCondition? | Imposed changing concentrations or emissions of historical short lived gas species |
| 2.1.bc.nat_aer | BoundaryCondition? | Imposed changing concentrations or emissions of historical natural aerosols |
| 2.1.bc.ant_aer | BoundaryCondition? | Imposed changing concentrations or emissions of historical anthropogenic aerosols |
| 2.1.bc.nat_aer_pre | BoundaryCondition? | Imposed changing concentrations or emissions of historical natural aerosol precursors |
| 2.1.bc.ant_aer_pre | BoundaryCondition? | Imposed changing concentrations or emissions of historical anthropogenic aerosol precursors |
| 2.1.bc.solar | BoundaryCondition? | Imposed historical changing solar forcing |
| 2.1.bc.LU | BoundaryCondition? | Imposed historical changing land use |
| 2.1.stc.1860_141yr | SpatioTemporalConstraint? | Begin in 1860 and run for 141 years |
| Required Duration: | 1860-01-01T00:00:00Z to 2006-01-01T00:00:00Z plus 141 years | |
| Required Resolution: | None | |
Experiment A1B
Provide estimate of future antrhopogenic climate change. Future projection (2001-2100) forced by A1B.
Within the SRES set, the A1B scenario forms a medium-high emission scenario driven by high economic growth, strong globalization and rapid technology development. The scenario also assumes a material-intensive lifestyle so energy consumption grows rapidly despite population growth being relatively low (the population peaks around 9 billion in 2050 and declines to around 7 billion in 2100). The energy supply as a balance between fossil fuel and non-fossil fuel sources. The A1B scenario has been chosen as the baseline scenario for the ES2 simulations because it provides overlap with earlier climate modelling work.
| 3.1.ic | InitialCondition? | Initial conditions are from the end of experiment 20C3M |
| 3.1.bc.wmg | BoundaryCondition? | Imposed changing concentrations or emissions of A1B well mixed gases, including CO2 |
| 3.1.bc.sls | BoundaryCondition? | Imposed changing concentrations or emissions of A1B short lived gas species |
| 3.1.bc.aer | BoundaryCondition? | Imposed changing concentrations or emissions of A1B aerosols |
| 3.1.bc.aer_pre | BoundaryCondition? | Imposed changing concentrations or emissions of A1B aerosol precursors |
| 3.1.bc.LU | BoundaryCondition? | Imposed changing A1B land use |
| 3.1.stc.2001_100yr | SpatioTemporalConstraint? | Begin in 2001 and run for 100 years |
| Required Duration: | 2001-01-01T00:00:00Z to 2100-01-01T00:00:00Z plus 100 years | |
| Required Resolution: | None | |
Experiment E1
Provide estimate of future antrhopogenic climate change. Future projection (2001-2100) forced by E1.
The experiment contrasts the A1B baseline with a corresponding aggressive mitigation scenario E1 (Lowe et al. 2009) developed with the IMAGE 2.4 IAM. Meinshausen et al. (2006) indicate that stabilization of GHG concentrations at 450 ppmv (CO2-equivalent) would provide a 20–75% probability of stabilizing temperatures below a 2 K warming target. Starting from an A1B baseline, a ‘‘peaking’’ scenario was developed which initially peaks at around 530 ppmv CO2-e and then decreases gradually to approach 450 ppmv from above during the twenty-second century. Den Elzen and van Vuuren (2007) show that peaking scenarios may be preferable to stabilization scenarios, on the basis of cost-effectiveness considerations, for reaching long-term temperature targets. The GHG concentration data for this experiment has been calculated using the IMAGE model.
| 4.1.ic | InitialCondition? | Initial conditions are from the end of experiment 20C3M |
| 4.1.bc.wmg | BoundaryCondition? | Imposed changing concentrations or emissions of E1 well mixed gases, including CO2 |
| 4.1.bc.sls | BoundaryCondition? | Imposed changing concentrations or emissions of E1 short lived gas species |
| 4.1.bc.aer | BoundaryCondition? | Imposed changing concentrations or emissions of E1 aerosols |
| 4.1.bc.aer_pre | BoundaryCondition? | Imposed changing concentrations or emissions of E1 aerosol precursors |
| 4.1.bc.LU | BoundaryCondition? | Imposed changing E1 land use |
| 4.1.stc.2001_100yr | SpatioTemporalConstraint? | Begin in 2001 and run for 100 years |
| Required Duration: | 2001-01-01T00:00:00Z to 2100-01-01T00:00:00Z plus 100 years | |
| Required Resolution: | None | |
