One square kilometer doesn't sound like much anymore. That would rank in size and population about 750th of modern American municipal centers or 3000th of Chinese.
You do realize why, for instance, oil spills which used to be measured in "barrels" are now reported in "gallons"?
I think the evolution of reporting them in teaspoons is now overdue.
Think about it. Grants, funding, yada yada.
Who do you suppose will get the grant? The one who reports a million square meters for study or the one who claims merely one square kilometer?