Cement emissions?

[bpbond]

Email from @ssmithClimate

I’m in a CMIP harmonization call, and looking at some of the interfaces for emissions -> SCMs. One issue that may come up is hector wanting some ore specific LULUC input that won’t be available from the CMIP process (where it looks like only the old-style net LULUC CO2 emissions will be provided.).

The issue of CO2 carbonization from cement just came up as well. Do we have that pinned as a potential issue to address from either the GCAM or hector side? Ideally we should include that in our modeling - I don’t have an opinion at this point if this better to do in GCAM and adjust the CO2 passed to hector or do this on the hector side (If not we should flag that for discussion.). It's a separate line item now in the global carbon budget.

[ssmithClimate]

For context, here is the magnitude of the cement carbonation sink since 2000 (from GCP 2023). These represent a flux from the atmosphere to land. Historical values we have from GCP, but part of the issue will also be how to calculate these for the future using GCAM data, so there's a GCAM linking question as well.

Year cement carbonation sink
2000 0.083536938
2001 0.086109401
2002 0.090522969
2003 0.097275016
2004 0.104064894
2005 0.111160968
2006 0.121018477
2007 0.130367979
2008 0.134660751
2009 0.141512386
2010 0.150279147
2011 0.162719085
2012 0.169239681
2013 0.177229223
2014 0.184932111
2015 0.185938922
2016 0.188003953
2017 0.192072616
2018 0.198195623
2019 0.201583196
2020 0.206857741
2021 0.216462506
2022 0.217464615

From GCB: Full details of the method are described in Friedlingstein et al (2023).