At times scientists can be their own worst enemy. In an attempt to be accurate, scientists sometimes forget the most basic rule of communicating: know your audience. In the case of explaining climate change, and in particular, explaining rising global temperatures, scientists have chosen to use the phrase 'global average surface temperature anomaly.'
Here's an exchange between 'FiveThirtyEight.com science editor Blythe Terrell and Gavin Schmidt, a climate scientist at the Earth Institute at Columbia University and director of the NASA Goddard Institute for Space Studies.'
blythe: So 2016 was officially the hottest year on record on Earth. Gavin, can you tell us what that means?
gavin: We have a dense enough network of weather stations and ocean records since about the mid-19th century to be able to estimate the global average surface temperature anomaly, and 2016 is the warmest we’ve seen in that entire period.
That comes on top of records in 2015, and before that, 2014.
Scientists who already know what a 'global average surface temperature anomaly' is will nod in agreement at Schmidt's explanation. But, the general readership of FiveThirtyEight will do one of two things: 1) Wonder what the hell a 'global average surface temperature anomaly' is, or 2) Stop reading because scientists use fancy language to try to cover up a bunch of magic and handwaving leading to the inevitable conclusion that scientists are making shit up to fool 'the deplorables.'
Fortunately, FiveThirtyEight knows their audience so they ask:
blythe: And when we say “global average surface temperature anomaly,” what do we mean?
gavin: Good question. What we do is we take each of the weather stations and other records and calculate the difference from what you expect at each month and year — that’s the anomaly. It turns out that the anomalies from one station to another are highly correlated — much more so than the absolute temperature. There’s a good explainer of this at the Goddard Institute for Space Studies “Surface Temperature Analysis” website.
Which raises my main point: why call it an anomaly? Scientists know that when they use the word 'anomaly' they are referring to 'the amount of deviation of a meteorological quantity from the accepted normal value of that quantity.' (definition 6 on Dictionary.com). But, I have a hunch that most people, when they think of an anomaly, think of definition 1, 2 or 3: something, odd, or peculiar, a one-off event that can be thrown away, an outlier,...
So if the goal is to try to communicate the science behind and reality of the global temperature trend, calling it an anomaly seems counterproductive: we don't expect anomalies to happen year after year.
I propose that we call it the 'Worldwide Temperature Figure,' and abbreviate it WTF.
Then we can write headlines like "NOAA says WTF Temperature Readings are at an All Time High."