Home/BlogThe Version 6.1 global average lower tropospheric temperature (LT) anomaly for September, 2025 was +0.53 deg. C departure from the 1991-2020 mean, up from the August, 2025 anomaly of +0.39 deg. C.
The Version 6.1 global area-averaged linear temperature trend (January 1979 through September 2025) remains at +0.16 deg/ C/decade (+0.22 C/decade over land, +0.13 C/decade over oceans).
The following table lists various regional Version 6.1 LT departures from the 30-year (1991-2020) average for the last 21 months (record highs are in red).
| YEAR | MO | GLOBE | NHEM. | SHEM. | TROPIC | USA48 | ARCTIC | AUST |
| 2024 | Jan | +0.80 | +1.02 | +0.58 | +1.20 | -0.19 | +0.40 | +1.12 |
| 2024 | Feb | +0.88 | +0.95 | +0.81 | +1.17 | +1.31 | +0.86 | +1.16 |
| 2024 | Mar | +0.88 | +0.96 | +0.80 | +1.26 | +0.22 | +1.05 | +1.34 |
| 2024 | Apr | +0.94 | +1.12 | +0.76 | +1.15 | +0.86 | +0.88 | +0.54 |
| 2024 | May | +0.78 | +0.77 | +0.78 | +1.20 | +0.05 | +0.20 | +0.53 |
| 2024 | June | +0.69 | +0.78 | +0.60 | +0.85 | +1.37 | +0.64 | +0.91 |
| 2024 | July | +0.74 | +0.86 | +0.61 | +0.97 | +0.44 | +0.56 | -0.07 |
| 2024 | Aug | +0.76 | +0.82 | +0.69 | +0.74 | +0.40 | +0.88 | +1.75 |
| 2024 | Sep | +0.81 | +1.04 | +0.58 | +0.82 | +1.31 | +1.48 | +0.98 |
| 2024 | Oct | +0.75 | +0.89 | +0.60 | +0.63 | +1.90 | +0.81 | +1.09 |
| 2024 | Nov | +0.64 | +0.87 | +0.41 | +0.53 | +1.12 | +0.79 | +1.00 |
| 2024 | Dec | +0.62 | +0.76 | +0.48 | +0.52 | +1.42 | +1.12 | +1.54 |
| 2025 | Jan | +0.45 | +0.70 | +0.21 | +0.24 | -1.06 | +0.74 | +0.48 |
| 2025 | Feb | +0.50 | +0.55 | +0.45 | +0.26 | +1.04 | +2.10 | +0.87 |
| 2025 | Mar | +0.57 | +0.74 | +0.41 | +0.40 | +1.24 | +1.23 | +1.20 |
| 2025 | Apr | +0.61 | +0.77 | +0.46 | +0.37 | +0.82 | +0.85 | +1.21 |
| 2025 | May | +0.50 | +0.45 | +0.55 | +0.30 | +0.15 | +0.75 | +0.99 |
| 2025 | June | +0.48 | +0.48 | +0.47 | +0.30 | +0.81 | +0.05 | +0.39 |
| 2025 | July | +0.36 | +0.49 | +0.23 | +0.45 | +0.32 | +0.40 | +0.53 |
| 2025 | Aug | +0.39 | +0.39 | +0.39 | +0.16 | -0.06 | +0.69 | +0.11 |
| 2025 | Sep | +0.53 | +0.56 | +0.49 | +0.35 | +0.38 | +0.77 | +0.32 |
The full UAH Global Temperature Report, along with the LT global gridpoint anomaly image for September, 2025, and a more detailed analysis by John Christy, should be available within the next several days here.
The monthly anomalies for various regions for the four deep layers we monitor from satellites will be available in the next several days at the following locations:
Warming goes on,
and Denying and Ignoring will goe on.
Same procedure as every month.
Richard M (last month):
“The change to the AMO cool phase is due soon.”
Oops. The latest value is the warmest in 5 months.
Third warmest September, though still a lot cooler than the previous two years.
Year Anomaly
1 2024 0.81
2 2023 0.80
3 2025 0.53
4 2019 0.44
5 2020 0.40
6 2017 0.39
7 2016 0.30
8 1998 0.28
9 2021 0.26
10= 2010 0.20
11= 2022 0.20
My projection for 2025 is now 0.475 +/- 0.068C, with a 90% chance that 2025 will be the 2nd warmest year on record.
As Roy noted the trend since the start is 0.16 deg/decade.
But the trend over the last 20 y is nearly double that, at 0.31 deg/decade.
The warming has accelerated.
True, but each and every deviation from a mean that takes place within a period of 30 years or less is part of the domain called ‘weather’. Nothing to do with climate right.
Yes, the trend is accelerating. The instantaneous rate of warming from a second order polynomial fit to the data is 0.27 deg/decade.
Called it 10 days ago (or so).
See https://oz4caster.wordpress.com/cfsr/.
It’s not controversial that the warming has accelerated since the ~1970s. It also decelerated (slightly) mid 20th century.
If there’s “settled” climate science, it’s the climate (temperature…) record of the last ~150 years. The global (AMO-like) pattern is supported by solid evidence.
Did Hunga Tonga erupt again?