To kick off Climate 2020, David Gelber and Jeff Nesbit discuss the whirlwind global climate strike and the UN Climate Action Summit, along with their initial impressions of the candidates' climate positions.

Then, we get insider insights from MSNBC's Chris Hayes, and we hear about a new climate news project from veteran journalist Kyle Pope. Then David and producer Janet Babin take a trip to a region of Pennsylvania that could decide the presidential election.