A new study calculates that human-caused climate change doubled the likelihood of the tinderbox weather conditions that sparked Canada’s massive summer wildfires. Thursday’s study by extreme weather research group World Weather Attribution says greenhouse gases make fire weather conditions such as heat, dry air and wind two times more common than they would be in a world without climate change. The fires spread smoke and raised the ire of U.S. President Donald Trump. He blames Canada for not managing its forest properly. Experts say Trump should look in the mirror. One Canadian fire scientist faulted the U.S. and Canada for not cutting back enough on fossil fuels and said the consequences could be deadly.