University of Colorado
|RFMIP: RFMIP-ERF: ozone specification for HistNat (please be consistent with DAMIP)|
|In RFMIP-ERF-HistAer and RFMIP-ERF-Aer, ozone concentrations should be fixed at pre-industrial values. In concentration-based models, the concentrations of ozone should be fixed, and in emissions-based models, the ozone in the radiation code should be fixed. As solar and volcanic forcings affect stratospheric ozone, this effect will be included in the hist-nat integration of DAMIP. To get a consistent ERF estimate modeling groups should include the same dataset in the RFMIP-ERF-HistNat experiment. David Plummer, in collaboration with Michaela Hegglin, has kindly agreed to develop prescribed ozone datasets for DAMIP hist-nat, which account for solar and volcanic effects and that data will be published on input4MIPs in due course. Therefore, we suggest that modeling centers using models without coupled chemistry wait until the prescribed ozone datasets are available before commencing these experiments.|
|08/11/2017 9:19 a.m. by Robert Pincus|
|RFMIP: Revision to RFMIP-ERF-AerO3 and RFMIP-ERF-HistAerO3 protocols|
| The manuscript describing the RFMIP protocol (http://www.geosci-model-dev.net/9/3447/2016/) includes two experiments designed to infer the effective radiative forcing from aerosols at present-day (RFMIP-ERF-AerO3 ) and over the historical record (RFMIP-ERF-HistAerO3). In the original protocol we allowed for aerosol and ozone concentrations to change together to allow participation by models using either specified concentrations or specified emissions (in which aerosol and ozone depend on each other).
After discussions with the Detection and Attribution MIP and the Aerosol-Chemistry MIP we have agreed to follow the DAMIP protocol for these simulations. The RFMIP data request changes the names of these experiments to RFMIP-ERF-Aer and RFMIP-ERF-HistAer. The protocol is also changed: ozone is to be held fixed at pre-industrial concentrations either in the entire model or, for emissions-based models, in the radiative transfer calculations.
Please let us know if you have any questions.
Robert Pincus, Robert.Pincus@colorado.edu, on behalf of myself and Piers Forster
|11/16/2016 7:47 a.m. by|