Jawoo Koo has the lowdown on that decision to use the SPAM crop maps for the yield gap atlas rather than, as it turns out, MIRCA2000’s:
The workshop organizer distributed MIRCA’s crop distribution maps to each country expert and asked for feedback on whether the maps adequately represented where the crops are (or aren’t) in terms of harvested area. Reviewing all the feedback comments and comparing the results against the SPAM data, the organizers established that “… In nearly all cases, the SPAM maps were more consistent with the feedback we received from the GYGA agronomists at the workshop.”
There are caveats, though. Read the full story.