More people are likely to take their own lives as the planet warms, say researchers at Stanford University and UC Berkeley in a study published Monday that suggests yet another worrisome impact of climate change. The multidisciplinary research team looked at nearly 1 million suicides in North America and found that hotter temperatures correlate with higher suicide rates. The warming projected through 2050, the group figures, could increase suicide rates by 1.4 percent in the U.S. and 2.3 percent in Mexico over that time, resulting in 21,000 additional deaths in the two nations. Lab co-director Solomon Hsiang, a co-author, explains the correlation.