README
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This dataset contains monthly SAT output from a study with the Norwegian Earth
System Model (NorESM) using proxy-based stochastic volcanic forcing to assess the
effects of volcanic uncertainty in probabilistic 21st century climate projections. 

Experiments:  
 historicalVolc: 1980-2005 simulations using historical volcanic forcing 
 historicalNoVolc (no-Pinatubo): 1990-2004 simulations with zero volc. forcing 
 rcp45Volc (VOLC): 2006-2099 simulations using different stochastic volc. forcings
 rcp45VolcConst (VOLC-CONST): 2006-2099 simulations using constant volc. forcing
 rcp45NoVolc (NoVOLC): 2006-2099 simulations with zero volcanic forcing 

Ensemble size and initialization: 
 Each experiment comprises 60 simulation members. 
 Note the original rcp45VolcConst from Bethke et al. 2017 comprised only 20 members 
 and members 21-24 have been produced later in support of the study Man et al. 2021. 

 The historicalVolc simulations are initialised from the three Jan 1 1980 states 
 of NorESM1's three CMIP5 historical runs (mem1-20 <- CMIP5 mem1, mem21-40 <- CMIP5  
 mem2, mem41-60 <- CMIP5 mem3). A small temperature anomaly i.e. micro-perturbation 
 is added the mixed layer temperatures of all members. Further details are provided
 in Section 4.2 in Outten et al. 2015. 

 The historicalNoVolc, rcp45Volc, rcp45VolcConst and rcp45NoVolc simulations are 
 all initialised from the historicalVolc experiment 

Variables: 
 tas - 2m air temperature 
 areacella - atmospheric grid cell area 

References: 
 Bethke, I., Outten, S., Otterå, O. et al. Potential volcanic impacts on future 
 climate variability. Nature Clim Change 7, 799–805 (2017). 
 https://doi.org/10.1038/nclimate3394

 Man, W., Zuo, M., Zhou, T., Fasullo, J. T., Bethke, I., Chen, X., et al. (2021). 
 Potential influences of volcanic eruptions on future global land monsoon 
 precipitation changes. Earth's Future, 9, e2020EF001803. 
 https://doi.org/10.1029/2020EF001803

 Outten, S., P. Thorne, I. Bethke, and Ø. Seland (2015), Investigating the 
 recent apparent hiatus in surface temperature increases: 1. Construction of 
 two 30-member Earth System Model ensembles, J. Geophys. Res. Atmos., 120, 
 8575–8596, doi:10.1002/2015JD023859