Guest Post by Willis Eschenbach
After an unusual three years in a row of La Nina (cool) ocean temperatures, alarmists are all in a lather about the sea temperatures as we approach El Nino conditions. We get claims like this:
Global oceans are so hot right now, scientists all around the world are struggling to explain the phenomenon. Sea surface temperatures in June are so far above record territory it is being deemed almost statistically impossible in a climate without global heating.
These overwrought claims are generally accompanied by charts like this:
Figure 1. Title says it all.
YIKES! Thermageddon is just around the corner! Be very afraid!! …
So … what’s not to like? Well, for starters, they’ve omitted the colder areas of the ocean, those near the poles. That’s cherry-picking to exaggerate any warming. But that’s just the start.
Those who read my work know I don’t generally trust the numbers until I run them myself. So I went to their data source. The data they used is the NOAA Optimum Interpolation Sea Surface Temperature (OISST) data. From the OISST website:
“The NOAA 1/4° Daily Optimum Interpolation Sea Surface Temperature (OISST) is a long term Climate Data Record that incorporates observations from different platforms (satellites, ships, buoys and Argo floats) into a regular global grid. The dataset is interpolated to fill gaps on the grid and create a spatially complete map of sea surface temperature. Satellite and ship observations are referenced to buoys to compensate for platform differences and sensor biases.”
Downloading the data took a while. It’s in 15,259 files, one for each day, each one 1.7 megabytes, total of about 26 gigabytes… good fun.
After downloading it all, I graphed up the daily values. But not the anomaly values shown above. I graphed the actual daily values of the sea surface temperature (SST) of the entire ocean, so I could see what the SST is actually doing.
Figure 2. OISST sea surface temperatures (SST) for the global ocean.
There are a few things worth noting in Figure 2.
- You can see the peaks of the previous El Ninos in 1998-99, 2010-11, 2016-17, and the currently developing El Nino.
- As is common with natural datasets, it changes in fits and starts, warming for a while, then cooling, then warming a bit more, then cooling …
- You can see the recent cool La Nina years just before the 2023 peak
- The temperature peak occurred on April 2nd, 2023, and the temperature has dropped about a quarter of a degree since then.
Finally, is this “far above record territory” as folks are claiming?
Well … in a word, no. The April 2nd temperature is 0.04°C warmer than the previous record set back in 2016.
Four. Hundredths. Of. A. Degree.
(And if we only look at the cherry-picked ocean from 60°N to 60° south [not shown], it’s a whopping 0.06°C …)
To put this into perspective, as everyone who has climbed a mountain knows, as you go up in elevation, the air gets cooler. This cooling goes by the fancy name of the “adiabatic lapse rate”. In general, it cools about 1°C for every 100 meters in altitude.
So in human terms, 0.04°C is about as much warming you’d get by going from the second floor to the first floor in a building … in other words, not even detectable without a very expensive thermometer.
Of course, the question arises: why is there such a difference between Figures 1 and 2?
The reason is simple. The warming in 2023 is occurring earlier in the year. The temperature is not unusually high. It’s unusually early, which is not surprising since we’re coming off of a few years of La Nina (cool) temperatures.
And this is why using anomalies rather than actual values, while useful in some situations, can lead you far astray in other situations.
Moving on, much of the hyperventilation involves the North Atlantic. Here are the SST anomalies for that part of the ocean.
Figure 3. As in Figure 1, but just for the North Atlantic.
Again, this looks like impending Thermageddon … but here are the actual temperatures of the North Atlantic.
Figure 4. OISST sea surface temperatures (SST) for the North Atlantic.
Unlike the global ocean, because this is the northern hemisphere only, there is a strong annual signal.
And again, there’s nothing out of the ordinary regarding maximum temperatures. In fact, maximum North Atlantic temperatures have been pretty steady since 2010. All that’s happening is that, like the global ocean, this year it’s warming earlier than usual.
- The 2023 Thermageddon Festival is canceled, and there will be no ticket refunds.
Best to all on yet another cold, foggy Northern California day. Me, I say bring on the global warming, or at least some dang sunshine.
As Usual: I politely request that when you comment you quote the exact words you are discussing. I choose my words very carefully, and I am happy to defend them. But I cannot defend your interpretation of my words. Thanks.