I had an email the other day that comes with a pretty simple answer:
Hello Frank. I have a question regarding the Gulf Coast. Why is the Gulf Coast so hot and generating so much warm moist air since we had a rather mild summer? … It just seems the Gulf Coast is the center of all the weather this year.
Thank you, Jacqueline
Let’s start with basics in that, yes, the water across the world (and the world is 70% water) continues to warm. Just today you can see all that red indicating so much warmer-than-normal water, especially north of the equator:
National Oceanic and Atmospheric Administration, or NOAA, offers this graphic below which shows how the ocean heat content has continued to increase above normal, showing cooler waters from 1960 to 1990 and warmer since:
What causes this warming?
The sun, more than anything, naturally heats the ocean, but factor in greenhouse gases, clouds and water vapor which give off heat and that extra heat is absorbed. Global warming is, as much as anything, ocean warming.
This warming creates at least two alarming phenomenon. First, when you heat anything, it expands (cooling contracts). So a warmer ocean expands and sea levels rise. This is in addition to any melting glaciers or ice sheets adding more liquid water to the equation. Clearly, higher tides create an issue for coastal residents. Second, warmer waters threaten ecosystems, coral and marine life. This, in turn, threatens those people who depend on our oceans for a living. Here’s a full report from NOAA.
Warmer water = wilder weather
Back to Jacqueline’s email, the Gulf waters are much warmer than normal. Take a look from temperatures today:
That warmer water, in addition to expanding and rising, translates to warmer air. Warm air rises. When it rises, it cools in the upper part of the atmosphere where it releases its energy, and that energy means stronger hurricanes and more severe weather moving on shore.
Just look at how quickly Hurricane Ida increased in strength last year: On Aug. 29, at 1 a.m., Ida had winds of 115 mph and five hours later, at 6 a.m., those speeds were at 150 mph! By 11a.m., Ida tore up Louisiana with those winds.
Hurricane Michael in 2018 exploded from a 110 mph storm to 155 mph in less than 24 hours before moving into the Florida Panhandle. Even Hurricane Hanna into Corpus Christi in July 2020 went from a 65-mph tropical storm to a 90-mph hurricane in less than a day. Matagorda County residents were walloped last September as Nicholas strengthened to a hurricane minutes before landfall.
Then, you look at this past December’s deadly tornado outbreaks in Illinois and Kentucky as warm, humid Gulf air met a cold front from the west. A disastrous winter event. Here in Southeast Texas just this month on Jan. 8 we saw a Gulf low drop 8-12″ of rain in Liberty County and produce five tornadoes. In JANUARY. The warm Gulf air is, for a very good reason, the center of attention these days.
The list goes on and on and so back to that simple answer: warmer world, warmer water, wilder weather.