Straight: We know that global warming is a reality and that we humans are its primary cause. And we know that carbon dioxide emissions, in large part from burning fossil fuels, are one of the biggest contributors to global warming. But we still have much to learn about the Earth’s mechanisms when it comes to regulating emissions and warming. Forests–along with grasslands, soils, and other ecosystems–are an important part of the equation, and a new report published in the journal Nature sheds …