redOrbit: Increasingly, the Earth’s climate appears to be more connected than anyone would have imagined. El Niño, the weather pattern that originates in a patch of the equatorial Pacific, can spawn heat waves and droughts as far away as Africa. Now, a research team led by Brown University has established that the climate in the tropics over at least the last 2.7 million years changed in lockstep with the cyclical spread and retreat of ice sheets thousands of miles away in the Northern …