Repeating myself from previous discussions, but here is an overview of the actual temperature data, looking at the global temperature anomaly with reference to 1960-1990, using HADCRUT4 (NH+SH)/2. First, the whole instrumented record, showing the annual temperature anomaly (peaky curve) and decadally smoothed data (to give a better impressin of overall trends:
Now, raw monthly anomaly data (much more noise):
Now the same monthly data, zooming into the last 65 years, and adding a 12 month trailing average (to give a better idea of trends):
Now the same thing, but zooming in closer, to post-1995, to focus on the recent "pause" people talk about:
And finally, a closer view from 2005-present:
Spend some time looking at and thinking about these plots of real data and you can draw your own conclusions. Some key points:
- average global temperatures have increased about 1C since 1850
- there is a fair bit of variability on the illustrated time scales, with some long periods of fairly steady increase and decrease
- 1975-1995 had the most dramatic overall increase
- 1995-present, temperatures have been relatively consistent (the "paus" in global warming)
- looking closer, we see a ~ 2 year cycle (as one of many)
- if you squnit while you look, you might expect (as I do) that the anomaly is due for a drop over much of the next year or so
- if you squint again at one of the other graphs, you might expect this current "pause" in global warming to last another 10-20 years before temperatures increas again.
My naive predictions from all this are the following, in descending order of confidence:
- this time next year, the 12-month trailing average anomaly (from HACRUT4 (NH+SH)/2) will be 0.1-0.15C lower than it is this month
- over the next 10-20 years, the 12-month trailing average anomaly will stay within a band between 0.4-0.7 above the 1960-1990 baseline average
- by 2100, the 12-month trailing average global anomaly will be abour 1.5-2.0C above 19660-1990 baseline values
That will be $0.02, thanks!