OK,
@Dexter, I read through the paper. Here's my brief take:
Global mean surface temperature is the most frequently cited indicator of climate change, with a steady upward trend since the 1970s
This is the first sentence of the introduction. It is not true. There have been many corrections, most of which have occurred fairly recently (within the last 10 years), as problems with older data and data collection techniques have been identified. Depending on erroneous, debunked, and outright falsified data renders the whole research invalid. I suppose that there is a tiny chance that they used the wrong data and got the right answer, but I'm not giving that much credence.
The authors use a period of 36 years. That is simply not enough time to demonstrate a true climate trend.
One of the most complex aspects of studying ETEs is that there is no formal definition of what an ETE is; indeed, in one recent paper 16 different definitions of heat indices were evaluated for the United States with differing spatial patterns of mean and, to a lesser extent, trends, based on the metric used ...
I'll let you ponder that one on your own.
And, my last point, which I can't prove, but have merely observed over time: I have read and evaluated a great number of research papers. The denser and more oblique the language, the less value to the paper. This one is particularly dense and appears to use language to baffle rather than make clear.
Thanks for posting the link. It was very enlightening.