

This is the third in a 10-part series about the ongoing global impacts of climate change. These stories will look at the current effects of a changing planet, what the emerging science suggests is behind those changes and what we all can do to adapt to them.
Hurricane Harvey slammed into Houston, Texas, on August 25, 2017. Normally, hurricanes keep moving. Their high winds and torrential rains tend to last for only a brief time. But Harvey just sat over the city. For days. And it dumped a lot of rain. Really, a lot. By the time the storm had moved on, on August 29, it had drowned Houston with a whopping 164 centimeters (64.6 inches) of water, according to one rain gauge. That’s a record rainfall from one storm in one place in the continental United States. In fact, Harvey dumped so much rain that the National Weather Service had to add new colors to their rainfall maps of the event.
Rising waters inundated more than 300,000 homes. That drove around 40,000 residents to take refuge in shelters across Texas and Louisiana. And of the some 100 people who died during the storm, more than 65 perished from flooding. Including damage from strong winds, researchers estimate that the storm caused more than $125 billion in damage. That tally makes Harvey the second-costliest hurricane to hit the U.S. mainland.
Hurricanes are a normal part of summertime weather. Since 1966, when satellites began daily monitoring of the North Atlantic Ocean, there have been an average of six hurricanes — and never less than two — per year. But more and more studies are revealing that human-caused climate change is influencing the size and fury of these storms.
And heavier rains and stronger storms are not the only ways in which a warming world is making our weather weirder. Higher temperatures can trigger droughts. Heat waves become more likely, and droughts can make them even worse. There can be changes to both global and local weather patterns. And the effects won’t always be what’s expected. In one truly odd twist, the continuing loss of summertime sea ice in the Arctic Ocean — one big result of a warming world — could make Siberian winters colder. What could be wackier than that?