World's Oceans At Record Warm Levels. Why You Should Worry

Chart shows ocean temperature trends. Click on the 
image to make it bigger and easier to see.
That black line is this year's overall ocean temperatures
and shows record high levels since late 
March of this year. Yellow line is 2022 and
the dotted gray line is the long 
term average temperatures 

 Here in landlocked Vermont, we should worry too much about warm ocean temperatures, right? Or even if you take an excursion to the New England coast this weekend, you'll turn numb immediately if you dip your toe in the water. 

So, everything's great, right?

Um, no. Not at all. 

The world's oceans, if you add up the water temperatures everywhere on Earth, are at record high levels. This has been going on for weeks now. And it's about to get more intense. 

As nature.com reports:

"What is remarkable is its occurrence ahead of - rather than during - an El Nino climate event that is expected to bring warmer, wetter weather to the the eastern Pacific region later this year." 

You and me both really don't care if it rains a lot over the eastern Pacific. But we do care a lot if this makes the weather get wonky and scary here or anywhere else on Earth where we might have loved ones or any kind of interest. 

The El Nino will continue to drive up ocean water temperatures in concert with climate change.  Warmer oceans contribute more moisture to the air than cooler water, so this trend toward toastier sea water will boost storms. 

Those storms will have an extra shot of moisture, so rainfall from some of these systems will be intense. Flooding will surely be an even more frequent visitor to news headlines than now.  Of course, it's not really possible to tell precisely who gets the storms and when. 

The warmer oceans also release heat back to the atmosphere, increasing the odds of record-shattering, dangerous heat waves. 

Regions of some oceans get temporarily very warm compared to normal. These are called marine heat waves. These heat waves can decimate fisheries and other marine life, and kill coral in affected areas.  

Ocean water temperatures began rising rapidly while a La Nina pattern was ongoing last year and early this year. La Nina is the opposite of El Nino and tends to suppress ocean water temperatures overall.  But lately, not really. Scientists worry about ocean water temperatures climbing more steeply in the coming months, especially if the El Nino that's coming on is particularly strong. 

Here's one other thing that might be suddenly making things worse. 

New rules put in place back in 2020 required ships plying the oceans to use fuel with a much lower sulfur content. This reduced sulfur dioxide emissions, which is a good thing in general. Pollution is bad after all, right?

The new standards mean much less acid rain falling into the oceans, which is a plus for marine life. However, an unintended side effect of this pollution fighting effort was to clear the skies over the ocean. Again, at first glance, this is a  good thing. The sulfur pollution from ships caused a haze over the oceans that dimmed the sun, preventing some of its heat from reaching the water surface,

Now, the sun is stronger without all that sulfur dioxide pollution, so more heat is entering the oceans in mid-latitudes, contributing to the upward trend in water temperatures. 

These high ocean water temperatures mean that the rough weather and climate ride the Earth has been on recently will get even more rough.