Nature: Scientists have found an unexpected link between El Niño climate episodes and human health. El Niño episodes, which entail a weakening of the Trade Winds across the South Pacific, can induce droughts in southeast Asia by suppressing monsoon rains; the lack of rain allows people to burn more land for agricultural use. As a result of increased levels of carbon particulates and ozone, air quality is diminished. The additional pollution can account for as many as 15 000 deaths in El Niño years, according to a study conducted by Miriam Marlier of Columbia University and colleagues. The good news, says Guido van der Werf, who studies global fire emissions at VU University Amsterdam, “is that these fires are all caused by humans, so in principle they can be prevented.”