Phenology, the ancient art of tracking annual phenomena such as plant blooms and bird migrations, is now a crucial tool in tracking the Earth's warming.Details here. Even with the context of plants blooming set up, and knowing this word (though it was not active vocabulary for me until now, probably), it was still hard not to get the other reading.
And then, 10 minutes later the announcer (Steve Innskeep?) says, "let's put this in the passive tense". Mavens will go wild, I imagine.