Greenhouse gas emissions

series_id definition change

The reporting_entity field shows that about 15% of rows have changed their entity code between the first and second half of the year, which is unusual. If the same location can report under different codes, that creates a matching problem in the time series. Should we standardize the entity codes, or should we note the instability?

The Copenhagen series resets completely in 2003, with no bridge data, and the notes say "new methodology adopted." Without overlap data, there's no way to establish whether the new series is at the same level or offset by a constant. Should we flag this as a comparability break, or do we have bridge-year data somewhere else?