Harvey came first, then Irma, followed by Maria. These are names millions of people won’t forget. Each represents a catastrophic hurricane that suddenly turned the lives of millions upside down, wreaking devastation, havoc, and prolonged hardship.
It’s easy to think climate change is to blame for these hurricanes. But, what do scientists say?
The fact is, it’s complicated. There are many complex factors in play. Nevertheless, certain facts lead to compelling conclusions.
What’s Causing These Massive Hurricanes?
A recent report produced by the National Climate Assessment, an interagency effort comprised of 13 federal agencies, indicates that the link between climate change and hurricanes is still not clear because they lack enough data beyond existing storm histories. And, each storm has its own unique conditions, which precludes it from an absolute link to climate change. In short, they need more time to find an emerging pattern.
What we can say with certainty is that hurricanes gain strength from unusually warm water in the Gulf of Mexico – a recent phenomenon. Warmer water is coincident with climate change. Temperatures are rising around the world, linked to greenhouse gases, which are linked to humans.
Thanks to global warming, there’s more atmospheric moisture. With Harvey, this increased moisture led to 51 inches of rainfall, triggering catastrophic flooding. Because of increased atmospheric moisture, scientists predict there will be more hurricanes like Harvey, with heavy rainfall.
Sea levels are also rising, making storm surges worse. Storm surges are seven inches higher than 30 years ago, according to a study by the National Oceanic and Atmospheric Administration. Rising sea levels are linked to rising ocean temperatures, and that has been linked to humans.
Expect Bigger, More Destructive Storms
Climate change doesn’t create hurricanes. They’re naturally occurring phenomena. But what’s different these days are the factors affecting them such as warmer water, more atmospheric moisture and rising sea levels. With these factors in play, once these storms form, they can rapidly intensify from a weak tropical depression to a Category 4 Harvey. Scientists predict that with these factors, there will be more destructive, more intense Category 3, 4, and 5 storms.
Summary & Implications
The reasons for these massive hurricanes are more nuanced than we might like. We might prefer simple answers to directly link or rule out climate change as a contributing factor. Nonetheless, scientific evidence proves that climate change has been linked to humans. Climate change is linked to global warming, and that, in turn, has affected ocean temperatures and the atmosphere. That said, how these factors contribute to the causes of storms like Harvey, Irma and Maria is complex.
While we await more data and studies, though, the facts speak for themselves. Within the last 10 years, significant storm events have increased along the Gulf Coast and East Coast. Rising sea levels and huge rainfall amounts put coastal areas at significant risk. How these states and cities will respond to the threat implies a strong commitment to tremendous infrastructure investments. In cities like Houston, uncontrolled growth and urban sprawl – along with a reluctance to address infrastructure vulnerabilities – reduced the city’s ability to cope with severe rainfall amounts. The new reality of these storms might require a new way of thinking about climate change.