Regional and temporal subsetting option can be found at: https://www.acom.ucar.edu/cam-chem/cam-chem.shtml. Note there is a limit to download data in chunks of 32 days.
*** Boundary conditions usually lag by approximately 6 months due to input file availability. Currently with COVID-19 the lag is longer. ***
Buchholz, R. R., Emmons, L. K., Tilmes, S., & The CESM2 Development Team. , (2019). CESM2.1/CAM-chem Instantaneous Output for Boundary Conditions. UCAR/NCAR - Atmospheric Chemistry Observations and Modeling Laboratory. Subset used† XXX, Accessed* dd mmm yyyy, https://doi.org/10.5065/NMP7-EP60.
†Please fill in the "subset used" with region and/or date of the subset you used (e.g. Lat: -10 to 10, Lon: 100 to 150, September 2015 - February 2016).
*Please fill in the "Accessed" date with the day, month, and year that you last accessed the data (e.g. - 5 Aug 2011).
We suggest to also cite the following paper that discusses the new configuration of CESM2/CAM-chem and assesses chemical species, including using output from this boundary condition simulation.
, , , , , , et al., (2020). The Chemistry Mechanism in the Community Earth System Model version 2 (CESM2), JAMES, submitted August, 2019.. Journal of Advances in Modeling Earth Systems, 12, e2019MS001882, https://doi.org/10.1029/2019MS001882.
Directions to access other experimental output can be found here: Benchmarks and Production