Interactive Reading

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When a volcano in Iceland erupts, the ash can travel far beyond the island. Fine particles rise high into the atmosphere and are carried by strong winds across the ocean. In 2010, one eruption sent so much ash over Europe that thousands of flights were grounded for days. Airlines lost enormous sums of money, and millions of passengers were stranded. The danger was not the ash falling to the ground but the risk it posed to jet engines, which can stall if they suck in the abrasive particles. Since then, aviation authorities have developed more precise ways to track ash clouds.