Yale Environment 360: The majority of Americans have limited understanding of the planet’s climate system and the causes and threats of climate change, according to a new study by Yale University. Only 1 in 10 of those surveyed by the Yale Project on Climate Change Communication said they are “very well informed” about climate change issues. And while 63 percent believe that global warming is occurring, many do not understand why. According to the survey, 57 percent of respondents know that the greenhouse …