New Scientist: IN JANUARY, climate researchers warned that extreme El Nio events are likely to become more common as the planet warms. It now seems that the world will have a chance to rehearse for the future as early as the end of this year. A major El Nio is massing in the Pacific Ocean and is likely to cause cyclones, tornadoes, droughts, floods and sea level changes across the world (see "World is unprepared for major El Nio later this year"). Many leading scientists say the approaching El Nio looks similar...