Last week on October 10, Hurricane Michael made landfall in Mexico Beach, Florida. Not stopping in Florida, the hurricane went on to affect Georgia, North Carolina, Alabama, and Virginia.
With winds of 155 miles per hour, the Category 4 hurricane killed at least 17 people, destroyed hundreds of neighborhoods, and downed power lines with over 1 million power outages have been reported since Hurricane Michael’s abrupt appearance.
The winds accompanying Hurricane Michael also brought toxic algae to the shores of Florida. This algae has killed marine life and caused breathing troubles for many people residing in the state.
Now, you would think scientists would be able to predict storms of this caliber. So why couldn’t they foresee the worst hurricane to affect the United States in the last 50 years?
How Michael Grew?
Well, Hurricane Michael was initially supposed to be a Category 1 tropical storm, with winds from 74-94 miles per hour. Read our earlier articles to understand how hurricanes form and what the various terms mean.
Then, the storm traveled through a patch where shear winds were so incredibly high. Shear winds refer to winds that change direction or speed as you go up in altitude. Scientists believed that those winds would either weaken the current Category 1 storm or completely break it apart. This is because Hurricane Michael’s eyewall -- a region of clouds, high winds and heavy rainfall surrounding the center of the storm (known as the eye), was punctured. Usually, a hole or an opening in the eyewall of a hurricane disables a storm from developing into its full potential.
However, Hurricane Michael was an exception. In a mere 48 hours after passing through the strong winds, Hurricane Michael strengthened into a storm with wind speeds nearing that of a Category 5 hurricane.
Scientists believe that the warm waters of the Gulf of Mexico caused the tropical storm to escalate into a Category 4 Hurricane Michael.
Warm waters are known to strengthen hurricanes as they add more heat and water vapor into the atmosphere that fuels the storms. Though it is hard to directly point to global warming as a cause, climate changes have been making our oceans warmer, and scientists urge us to consider the impact of more frequent and intense storms.
Hurricane Michael had another distinctive feature -- "hot towers." These are tall thunderstorms that form in the eyewall of the hurricane and extend all the way up into the stratosphere where planes fly! Think of it like a chimney or smokestack.
Why do hot towers form? When water vapors condense to form clouds, they release heat, which is known as latent heat. This can cause areas of instability in the eyewall of the hurricane and can cause the warm air to be swept up higher into the atmosphere. Studies have shown that hurricanes with hot towers are more likely to intensify.
Forecasting hurricanes is not an easy task and depend on conditions at any given moment as Michael has shown us. Check out this video that explains hot towers.
Sources: NASA, TheVerge, NYTimes, PBS, Phys.org