part and that same year the government created the epa and now people concerned about the regulations being rolled back. are you concerned at all? >> yeah, i think the challenge for me is that a lot of these problems i feel science isn't partisan. i feel that for us to come up with solutions, we need to understand the problem. i personally believe that science is what is going to help us define the problems and then we can start having political discussions. >> reporter: so those are the sentiments here in san francisco. >> thank you so much, sara sidner and miguel marquez, our appreciation to both of you being out in the crowds. up next here in the newsroom, another airline controversy, this time involving american airlines. now a flight attendant is suspended after video of an altercation with a page went viral. the video and the back story just minutes away here in the "cnn newsroom." [ceo] welcome.