This story was originally published by Grist and is shared here as part of the Climate Desk collaboration. So far, 18 Democrats have announced bids to tussle with Donald Trump for the presidency in 2020, with more expected to throw their caps in the ring. In such a crowded field, it’s hard to decipher where each candidate stands on any issue, including climate change — a topic that was conspicuously absent in the 2016 election but appears will be front and center this time around.