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Interesting; could that be caused by most cities being near sea level and most people living near cities, and thus pollution rather than oxygen might be the roo
by nitrogen 7y ago
Interesting; could that be caused by most cities being near sea level and most people living near cities, and thus pollution rather than oxygen might be the root cause?
- copperx 7y agoI don't have a link to the study, but the researchers of the study I read were very meticulous and did discard all other obvious explanations before concluding that altitude was the best explanation.