Input data set: Atmospheric composition (ISIMIP3a)

Climate related forcing: Globally averaged co2 and ch4 annual data covering the periods 1850-1900 (transclim), 1850-2021 (obsclim, spinclim), and 1901-2021 (counterclim).

The co2 data for 1850-2005 is taken from Meinshausen et al. (2011), and for 2006-2019 from Dlugokencky & Tans (NOAA/GML). The ch4 data for 1850-2014 is taken from Meinshausen et al. (2017), and for 2015-2019 from Ed Dlugokencky (NOAA/GML).

When referring to the co2 data sets, the following papers should be cited:
- Meinshausen, M., Smith, S.J., Calvin, K. et al. The RCP greenhouse gas concentrations and their extensions from 1765 to 2300. Climatic Change 109, 213 (2011). https://doi.org/10.1007/s10584-011-0156-z
- Ed Dlugokencky and Pieter Tans, NOAA/GML (https://gml.noaa.gov/ccgg/trends/)

When referring to the ch4 data sets, the following papers should be cited:
- Meinshausen, M., Vogel, E., Nauels, A., et al. Historical greenhouse gas concentrations for climate modelling (CMIP6), Geosci. Model Dev., 10, 2057–2116 (2017). https://doi.org/10.5194/gmd-10-2057-2017
- Ed Dlugokencky, NOAA/GML (https://gml.noaa.gov/ccgg/trends_ch4/)

For ISIMIP participants, these files are available for download on the DKRZ cluster server using the path ISIMIP3a/InputData/climate/atmosphere_composition/

For external users, these data can be downloaded from the ISIMIP Repository using the link below.