Temperature Update - August 2018, GISTEMP

Quick and dull update for GISTEMP.

GISTEMP has the anomaly for August 2018 at 0.77°C, making this the 5th warmest August on record.

August was almost identical to July's 0.78°C, and 4 of the months this year have been between 0.75 and 0.78°C, and all but two month have been within a 10th of a degree of each other.

Monthly temperatures continue to be very close to the trend since 1970, of 1.8°C / century.

Prediction

The prediction for 2018 is now 0.819 ± 0.067°C, compared with last month's prediction of 0.823 ± 0.079°C, and the average of the first 8 months of 0.811°C.

Probability forecasts based on previous variability suggests there is now a better than 90% chance of finishing in 4th place, with less than 1% chance of finishing below 4th.

GISTEMP

Rank	Year	Anomaly	Probability	Cumulative
1	2016	0.99	0.00%	0.00%
2	2017	0.9	1.23%	1.23%
3	2015	0.87	7.09%	8.31%
4	2014	0.73	91.01%	99.33%
5	2010	0.7	0.64%	99.96%
6	2005	0.67	0.03%	100.00%

Personal Prediction

I think it is almost certain that GISTEMP will finish in 4th place. To finish above 2015 would require an average anomaly over the last 4 months of 0.99°C. The only time the last 4 months of the year were this warm was in 2015, which was at the start of a massive El Niño, and then the average was only slightly warmer at 1.01°C, it seems highly unlikely that this will be repeated this year.

Conversely, to finish below 2014 for 5th place would require the last 4 months to average around 0.57°C, almost a quarter of a degree cooler the the average of the year to date. The last time the end of the year was this cold was 2011, during a moderate La Niña, following on from a very strong La Niña the previous year.