Earlier quoted context omitted.
The chart is a chart of the yearly "anomaly". So even a 0.3 degree deviation is plotted in the chart as an "anomaly". Clearly you don't understand the issue, which is exactly my point. It is a misleading label. I am not saying the rise by whatever many degrees is not an anomaly. That is simply not what they plot. They don't call the steep rise an anomaly, they call every deviation from the arbitrary average an anomal…
Pre-1920 is roughly in-line with average, 1920-1970 looks to be above average but could be argued to be within normal range of variation, post-1970 is clearly above normal range of variation. Your concern seems to be (1) that there is some negative connotation to the word "anomaly", (2) that the chart labels small differences anomalies rather than just large differences, despite small differences being possibly withi…
Except you also seem to misunderstand the use of the word, as it is completely unrelated to there being a "deviation towards higher temperatures". At most you could argue that it doesn't matter if people misunderstand it, as there happens to actually be an "anomaly" anyway.
About the reference time frame - I think things were going on before, like mini ice ages and what not. However I merely wanted to point out that the timeframe is arbitrarily chosen, not that it is necessarily a bad choice. In combination with the word "anomaly" it becomes more questionable as it kind of implies that those 10 years were "normal".