http://www.sciencemag.org/news/2018/06/hurricanes-are-slowing-down-wreaking-havoc-coastal-communities

In 2017, Hurricane Harvey stalled for 4 days over southern Texas, dropping more than a meter of rain and causing $125 billion in damage (above). It isn’t clear whether climate change is to blame, but ultimately, the storm’s sluggish speed is part of a bigger pattern: Tropical cyclones around the world—including hurricanes and tropical depressions—have slowed by 10% over the past 70 years, according to a new study.

Scientists have been predicting that cyclones will move more slowly as the world warms and tropical air circulation patterns—which ferry storms from one place to another—weaken. But one scientist with the U.S. National Oceanic and Atmospheric Administration decided to look back in time, to see what happened in the past. He looked at tracks of 7585 tropical cyclones from 1949 to 2016 and calculated their speeds before and after landfall.