I wrote Global Cooling almost exactly two years ago. In it I noted that my part of the UK had experienced a very cold winter, and I also observed that the database of the US National Oceanic and Atmospheric Administration (NOAA) was showing a 0.52C year-on-year fall in global land and ocean surface temperature between February 2020 and February 2021. Since I wrote that, I have been keeping an eye on NOAA’s monthly global climate report with a view to seeing whether or not that cooling trend was continuing.
The strange thing I have noticed is that although land temperatures don’t seem to be doing anything dramatic, NOAA’s monthly reports are full of hyperbole about global temperatures generally. For instance, the report published earlier this month in respect of April 2023 assures us that “April 2023 was the fourth-warmest April for the globe in NOAA’s 174-year record.” Yet, at the same time, we learn that although “Africa had its fourth-warmest April on record”, “South America tied 2007 for its ninth-warmest April” and it was only the 22nd warmest April on record in Asia, with the smallest April temperature anomaly since April 2010. In Pakistan, the national mean temperature for April was actually 0.26°C below the average. Meanwhile, North America, Europe and Oceania all saw April 2023 ranking outside the 20 warmest Aprils on record. Arctic sea ice saw only the eleventh smallest April extent on record (tied with April 2004). We are told that parts of Antarctica saw temperatures above average, but parts were below average, so there’s nothing much to see there either. Intriguingly, we also learn that “[l]ess than 1% of the world’s surface had a record-cold April.” That sounds pretty undramatic, but it does mean that some parts of the earth’s land mass saw a record cold month in records going back 174 years:
Coinciding with the release of the January 2023 Global Climate Report, the NOAA Global Surface Temperature (NOAAGlobalTemp) dataset version 5.1.0 replaced version 5.0.0. This new version includes complete global coverage and an extension of the data record back in time an additional 30 years to January 1850.
As for the year to date, it’s a similar story:
The January–April global surface temperature also ranked fourth warmest in the 174-year record at 1.03°C (1.85°F) above the 1901–2000 average of 12.6°C (54.8°F). According to NCEI’s statistical analysis, the year 2023 is very likely to rank among the 10 warmest years on record.
So, global warming continues unabated, then. Or does it? Not on land, it doesn’t. So far as the year to date is concerned, Europe and Africa apparently both come in with the third warmest, but South America saw only its seventh warmest first four months of the year, while Asia came in with the ninth warmest, North America with its fifteenth warmest, and Oceania tied with 1992 for the twenty-third warmest start to the year to date.
What is the explanation? It seems to be that sea surface temperature warming is ongoing (“Global ocean temperatures set a record high for Apr, and marked the second-highest ocean temperature on record for any month”), but that temperatures on land aren’t being so obliging to the alarmists. I thought I’d take a look at land temperature anomalies, and since 2016 is still said to be the warmest year on record, that seemed like a good place to start.
The global temperature across land surfaces for April 2016 set a new record, at 1.93C above the 20th century average. By April 2017 that anomaly had collapsed to just 1.37C above the twentieth century average, and was the joint fourth highest April temperature in the (then) 130 year record, the same as 2000 and 2010. April 2018 saw another fall, albeit more modest, to 1.31C above the average, and was thus only the ninth warmest April within the database. April 2019 saw rising temperatures, and came in at 1.48C above the average, making it the joint third April (tied with 2012). April 2020 saw another rise, to 1.66C above the average, and the excitement was palpable – it was second only to 2016. April 2021, however, saw the significant temperature drop I noticed when writing two years ago. It was just 1.25C above the twentieth century average, and was in a paltry twelfth place in the record books. April 2022 came in at 1.45C, warming alarmist hearts, as it was back up to sixth place. Yet April this year was cooler again, at just 1.31C above the twentieth century average, and registering 11th place in the record books. So here we are with land temperatures in April 2023 sitting at a whopping 0.62C below the record set in April 2016.
Of course, nobody will be talking about that. Interestingly, the northern hemisphere land temperature in April 2023 was only the 17th highest on record, yet the southern hemisphere land temperature is said to be the second highest on record. Year to date, by the way, sees southern hemisphere land temperatures as the tenth warmest on record, but northern hemisphere land temperatures as the fourth highest on record. Make of all that what you will.
Meanwhile, I would welcome an explanation as to how the southern hemisphere land temperature for April 2023 can be the second highest on record, while its constituent parts were all ranking much lower in the record books. Remember – South America joint 9th; Oceania outside the top twenty; Asia (granted it’s more a northern than a southern hemisphere continent), 22nd warmest; and Africa (also straddling the equator), fourth warmest.
I can’t help wondering if there’s really much point to all of this. I’d also like to know more about the latest dataset version, but that’s for another day.
Mark, I wonder if this has something to do with the constant adjustments to the temperature field algorithm, as I mentioned here ?
Alas, the value when it is announced is not a permanent record of what the temperature was. It is rather malleable. Another issue is the excessive precision, where NOAA claims to know the global temperature to within a hundredth of a degree. I doubt this is realistic.
Yes, very possibly. At first blush the NOAA work and website are very impressive, but I can’t help wondering if they’re worth a row of beans in reality.
Is this topic about weather or climate? I’m reasonably sure it doesn’t correspond to climate since the averages only involve time periods of maximum 31days, not 30 years. They are something in between. One might determine how temperatures progressively changed over 30 year periods using this data but I have never seen this done. Such changes averaged over years might indicate climate changes and in which season maximum changes might be occurring.. These are definitely occurring since I recall successive snowy Christmases in London as a boy (not occurring for many decades) and an absence of real pea-souper fogs in Novembers in Norfolk, something that definitely occurred each year when I first moved to Norwich but have been absent in successive recent winters.
It’s really about the utility (or otherwise) of statistics; about noting the warming sea surface temperature and observing that it doesn’t seem to be matched on land; about how that distinction is lost sight of by talking incessantly about combined sea surface and land temperature (how on earth do you establish such a thing?); and about how the mainstream media are oblivious to the difference.
For instance we are continually being told that warmer air is capable of holding more moisture, so a warming planet increases the chance of flooding. But what if the land surface and the air above it isn’t warming much, and the much-vaunted warming is mostly driven by rising sea surface temperatures?
I acknowledged in the global cooling article that this article follows on from, that these measures might be useful to ascertain medium to long term trends in climate, but even then we need to understand the numbers much better than the media do, rather than fudging them.
I also continue to have doubts about new temperature series replacing old ones, and things such as that mentioned above by Jit and discussed in his linked article.
I didn’t write a conclusion because I wanted people to contemplate the implications for themselves, and in doing so possibly making different points to the ones that occur to me.
Some extra statistics that I should perhaps have included in the article. Remember that we’re always being told that the high latitudes are warming far more quickly than equatorial and sub-equatorial regions. E.g.:
“The Arctic is heating up nearly four times faster than the whole planet, study finds”
Well, NOAA’s monthly report just in says that Antarctic land & ocean combined saw April 2023 as the 7th warmest on record and the Arctic saw April 2023 as the 22nd warmest. As for the year to date (i.e. Jan-Apr 2023), Antarctic is experiencing the 43rd warmest start to the year, while the Arctic has seen the 9th warmest.
These don’t mark anything of any great significance in themselves, long-term trends being the things to watch, but as with some of the other statistics, I don’t exactly see how they fit the ongoing alarmist narrative.