World’s corals under threat
24 February 2016
The current El Niño weather phenomenon is taking its toll on coral reefs, prompting a field campaign to the middle of the Pacific Ocean to explore how Europe's Sentinel-2 satellite might be able to quantify the damage on a large scale.
El Niño is an irregular oscillation in tropical Pacific currents, with wide-ranging consequences.
It begins when a mass of warmer water from the tropical western Pacific moves east, eventually displacing cooler nutrient-rich waters off the west coast of Central and South America. This warmer water adds extra moisture to the air masses moving over the ocean and increases rainfall in the adjacent land areas.
It also disrupts atmospheric circulation, leading to large-scale weather anomalies across the globe.
The impact can include severe drought in Africa, increased rainfall in South America, fires across southeast Asia, severe winter storms in California, a heatwave in Canada and intense hurricanes raging along the Pacific Ocean.