Rice cultivation contributes 2.5 percent of human-induced greenhouse gases. Two particular gases are the culprits. One is methane, a short-lived greenhouse gas that is 25 to 80 times more impactful than CO2. Rice contributes 12 percent of total global methane emissions. Nitrous oxide (N2O) is the other contribution. It is a long-lived greenhouse gas emitted by rice and is 300 times more potent than CO2. Read more in the New Security Beat