Temperature Update - August 2018, UAH

A quick update from Dr Roy Spencer with the UAH satellite data for August. This was 0.19°C above the 1981-2010 average, down from 0.32°C last month, closer to most of the year's anomalies, suggesting July was a bit of a spike in the satellite data. This makes 2018 the 9th warmest August.

August returns UAH back to the cluster of months just below the long term warming trend, which is currently 1.27°C / century. Though in contrast to the surface data the average of the last 12 months remains above the trend.

Predictions

Little change to the prediction for 2018, at 0.252±0.066°C, compared with last month at 0.256±0.074°C.

This compares with the current average over the first 8 months of 0.228°C. In order to hit the forecast will require an average of over 0.3°C for the next four months, about as warm as the warmest month this year. I suspect therefore unless there is an el Niño, the prediction will continue to fall, and the following should be taking with a moderate amount of salt.

At present and with the above in mind my statistical method suggests 6th or 5th place is most likely, with just over 50% chance of 6th place and just under 30% chance of 5th. There's a reasonable (~ 1 in 6) chance of finishing below 6th in which case the rankings could fall quickly with 10th being a distinct but small possibility.

UAH 6.0

Rank	Year	Anomaly	Probability	Cumulative
1	2016	0.52	0.00%	0.00%
2	1998	0.48	0.00%	0.00%
3	2017	0.38	0.02%	0.02%
4	2010	0.34	0.47%	0.49%
5	2015	0.27	28.40%	28.89%
6	2002	0.22	56.87%	85.76%
7	2005	0.2	8.88%	94.64%
8	2003	0.19	2.78%	97.41%
9	2014	0.18	0.84%	98.26%
10	2007	0.16	1.40%	99.65%
11	2013	0.14	0.29%	99.94%
12	2001	0.12	0.05%	99.99%
14	2009	0.1	0.01%	100.00%

It is remarkable how resilient the predicted value for UAH has been throughout the year, with the current prediction little changed from January.

Other data sets have seen more movement and it might be worth investigating the differences later.