Thread by @WeatherProf

Global Sea Surface Temperatures are at record levels, and not just by a little. The North Atlantic is a whole 1 degree F above record territory. From a meteorologist perspective there are few words to describe how out of bounds that is. So what is going on?? Thread...

Lots to discuss. There are a few marine heat waves you can see on this map. North Pacific. Equatorial Pacific. Tropical Atlantic. And NE Atlantic. Let's start with the Equatorial Pacific because that is the most obvious... El Nino.

There's a natural redistribution of waters in both basins every couple/ few years. Oscillations. These are normal. When the "relative" warmest water gathers around the Equator, esp across the Tropical Pacific because it is so large, you end up with large departures from normal..

It’s similar in the Atlantic. The basin is larger in the Tropics. And this year natural cycles have coincidently redistributed the relative warmest water into the Tropical Atlantic. Again causing large departures from normal. The Atlantic pattern is termed a +AMO but there more..

While these natural cycles act on a year to year basis, this is happening on top of human influence. Over decades ocean temps have warmed generally by around 1.5 to 2 degrees F. This is due mainly to greenhouse warming, but also the reduction of air pollution esp in Atlantic…

The oceans absorb just less than 90% of excess heat due to greenhouse warming. So they have been significantly heating. Also, on the man-made front, let’s talk about pollution and it’s impact…

After the Clean Air Act in the 1970s the air above the Atlantic has gradually cleared. That’s enabled extra sunlight to be absorbed and helped warm as well. Add to that, in 2020 ships were forced to significantly limit Sulphur emissions. Again limiting pollution’s cooling effect.

Lastly you need to consider weather. Sometimes resilient patterns set up that warm the underlying ocean. Bottom line: a multitude of factors have compounded to result in unprecedented ocean temps. But as long as we continue to warm the climate, the baseline will continue to rise.