Has the frequency of hurricanes increased due to climate change?
Hurricanes are complex storm systems and we don’t have enough historical data to be conclusive on the question of increasing frequency. The science linking the increasing frequency of hurricanes to higher global temperatures is divided and may likely depend on which part of the world we are looking at.
Has the intensity of hurricanes increased due to climate change?
Based on a few simple principles of chemistry and physics and evidence of larger and more intense storms hitting coastal regions around the world, most scientists agree that the intensity of hurricanes increases with hotter global temperatures. Here’s why:
- Rising sea-levels, due to melting ice at the poles, gives the hurricane an extra step on to land. The “storm surge” (rising of the sea level associated with a storm) has a head start which makes it stronger when it hits the land and allows it to devastate people and places further inland.
2. Warmer air holds more moisture thus when it rains, it pours. The hurricane pulls the warm air and moisture from the ocean to the land where the air is cooler. As the warm air cools and condenses the moisture becomes heavy rain which combines with the storm surge to cause major flooding.
3. Warmer ocean temperatures provide more heat energy to the tropical storm or hurricane as it forms and fuels the storm as it travels towards land. The speed of the winds will likely be intensified.
Does climate change cause hurricanes?
No, there have always been and will always be hurricanes. Hurricane Harvey was not caused by increased global temperatures but it likely spun into a once-in-500-years storm because of the factors outlined above.
Understanding the science behind these severe weather events is about more than pointing fingers and “I told you so,” it is about identifying high risk areas and finding ways to mitigate the destruction. It is about being prepared for more refugees of the climate crisis as a greater expanse of the world becomes uninhabitable. It is about changing our behaviour in order to slow the planet’s warming and interrupt these trends.
It’s not just for us.