We developed an experimental design for CMIP6, and are developing modifications to this for future experiments and towards CMIP7.

HighResMIP CMIP6 protocol

The HighResMIP protocol is described in detail in Haarsma et al 2016. It was one of the official MIP projects for WCRP’s CMIP6 HighResMIP.
The HighResMIP output requirements are described in the Data Request.
Below is a short outline of the protocol

Tier 1: Forced-atmosphere runs 1950-2014

Experiment name: highresSST-present: Using HadISST2.2.0.0 1/4 degree SST and sea-ice forcing dataset - see sst-and-sea-ice-forcing

Tier 2: Coupled runs 1950-2050

Control: 100 years with 1950’s forcing. Experiment name: control-1950
Historic: 1950-2014 with historic forcing. Experiment name: hist-1950
Future: 2015-2050 with SSP585 forcing. Experiment name: highres-future
Spin-up: 50 year spin-up from EN4 ocean climatology with constant 1950’s forcing. Experiment name: spinup-1950

Tier 3: Forced-atmosphere 2015-2050 (2100)

2015-2050 with SSP585 forcing (and future SST/sea-ice fields). Experiment name: highresSST-future

Motivation of these three Tiers

Focus of HighResMIP is on the 1950-2050 period (Tier 2). This period includes significant past changes and the time horizon for the future is relevant for decision makers.

The division of the forced-atmosphere (AMIP-style) runs in Tier 1 and Tier 3 is to enable NWP centers to participate. It also includes the possibility for end of the century simulations.

Resolution: Atmosphere 20-50 km; Ocean ~0.25 degree

Experiments are repeated with standard resolution. This version is also the entry for DECK runs.

HighResMIP philosophy: No or minimal additional tuning for high resolution version. If tuning is necessary it should be well documented.

Further proposed targeted experiments

We never had enough groups willing to do additional idealised experiments, but these may be ideas to take forwards into the updated HighResMIP:

Leaf area index (LAI) experiment highresSST-LAI
Smoothed SST highresSST-smoothed
CFMIP style experiments highresSST-p4K; highresSST-4co2
Abrupt 4XCO2 highres-4co2