Can we say for certain that Hurricane Matthew was caused by climate change? Scientists say no, with a big
but. No,
but the trends of climate change symptoms certainly point towards hurricanes, which need warm water, moist air and converging winds to form. No,
but a number of studies have found that warmer ocean temperatures are fueling stronger North Atlantic hurricanes. No,
but the number of North Atlantic Category 4 and Category 5 hurricanes has roughly doubled since the 1970s. In the case of Matthew, ocean waters were at record high temperatures because the North Atlantic has warmed more than other oceans at 0.7°C since the 1980s.
"We expect to see more high-intensity events, Category 4 and 5 events, that are around 13% of total hurricanes but do a disproportionate amount of damage," Kerry Emanuel, a professor of atmospheric science at MIT,told The Guardian. "The theory is robust and there are hints that we are already beginning to see it in nature."
"Last year was the warmest our oceans have ever been on record. And that's critical context," Michael Mann, a professor of atmospheric science at Penn State University, told Democracy Now. "It's that warmth that provides the energy that intensifies these storms. And it isn't a coincidence that we've seen the strongest hurricane in both hemispheres within the last year."
By 2100, tropical hurricanes are expected to be 2% to 11% more intense because of global warming,according to the National Oceanic and Atmospheric administration, citing UN data.
Global warming also is expected to make hurricanes produce about 20% more rain near the eye of the storm, according to a US government report. That's critical because freshwater flooding is the second deadliest feature of hurricanes, Emanuel told CNN.
There was previously far more certainty among climate scientists over the increase of temperatures than trends in hurricanes, but government officials arenow confident enough to say there has been a “substantial increase” in Atlantic hurricane activity since the 1980s, with the destruction set to ratchet up further as the world warms.
As the Guardian explains, “Hurricanes draw their energy from the ocean, which is currently acting like a sponge for the extra heat accumulating in the atmosphere due to human activity. Warming is thereby supercharging hurricane wind speed, with increased moisture delivering buckets of extra rain to affected areas,” like those who suffered from Hurricane Matthew.
An article posted by the Union of Concerned Scientists states: Globally, sea level has risen around 8 inches, and local factors have caused greater increases in some places, especially on the East Coast. Since the early 1900s, seas have risen about 10 inches at Mayport, Florida, and about 12 inches at Fort Pulaski, Georgia, and Charleston, South Carolina (based on NOAA tide gauges). This means that storm surge in those areas is riding in on seas 10 and 12 inches higher, and as a result the surge reaches further inland. Keep in mind, the water keeps moving inland until the ground rises slightly, and many states in the Southeast are very flat near the coast.
So in conclusion, no Hurricane Matthew was not 100% certainly caused by climate change,
but…
Sources:
CNN,
The Guardian,
Union of Concerned Scientists
