N_r99PDX

Purpose of simulation: Estimate the effect of BC on global and Arctic climate

Contact person: Alf Kirkevåg (alf.kirkevag@met.no)

Data owner: Alf Kirkevåg (alf.kirkevag@met.no)

Revision Number: r99

Production computer used: Cray XT in Bergen (hexagon)

Production date: October - November 2010

Storage locations: NorStore (/norstore_osl/projects/NS2345K/noresm/cases/N_r99PDX), where X = yr116, noBCyr116, noBCdepyr116

Storage space: 1500 Gb at NorStore

Projects: EarthClim/ACCESS

Publications:

Papers in preparation: Sand et al. (submitted)

Simulation name(s): N_r99PDX, where X = yr116, noBCyr116, noBCdepyr116

Compset name used: NAER2000

Model type: Fully coupled

Type of run: Initial

Simulation period: 92 years

Spin-up period: 116 years

Initialisation:

Ensemble runs: No

Resolution: f19_g19 = 1.8×2.5

Emission year(s): 2000 (aerosols and precursors), but BC emissions set to 0 for X = noBCyr116. For X = noBCdepyr116 BC emissions are for year 2000, but deposition of BC on snow and sea-ice is set to 0.

Emission inventories IPCC AR5, see references in Kirkevåg et al. (2013)

Greenhouse gases: Prescribed concentrations (2000?)

Frequency for output: Monthly (for atm, ocn and lnd)

Active/changing forcing agents: Direct and indirect (1. & 2.) effects by anthropogenic SO4, POM and BC. The effects of all BC is found from the difference between the experiments N_r99yr116 and N_r99noBCyr116, and the effect of BC deposited on snow and sea-ice is found from the difference between N_r99yr116 and N_r99noBCdepyr116.

Special considerations:

Tuning parameters which are changed relative to the host model CCSM4:

rhminl: 0.90 lower RH threshold for formation of low stratiform clouds (0.91 in CAM4)

critrp: 5.0 mm/day maximum prcipitation rate for suppression of autoconversion of cloud water (0.5 mm/day in CAM4)

r3lc: 14 um critical mean droplet volume radius for onset of autoconversion (10 um in CAM4)

R_snw: 500 um grain size of cold snow overlaying sea-ice (250 um in CICE4)