Papering over “overshoot”
What’s going on with these “overshoot” scenarios coming out of the IPCC?
In his latest ode to collapse, Umair, our resident Casandra here on Medium, mentions how many of our more recent IPCC climate scenarios involve the idea of “overshoot”, which he describes as a process in which:
“the temperature rises, and then it comes down, doing a whole lot of damage along the way”
One commentator replied that maybe Umair didn’t understand the term “overshoot”, which has a well-known and long-established different meaning. Another commentator replied that Umair was using the term correctly, but this was a newer meaning of “overshoot”, not the original one.
I added a reply to the thread, raising a related question: why obscure a well-established term by giving it a new meaning unrelated to its original meaning? Let me just say it got my Spidey Sense tingling. Here’s what I wrote (I’ve added some references for context).
You are right that Umair is not using the term “overshoot” here as it has traditionally been used since Catton’s 1980 book. This is a new use of the term introduced recently to describe climate scenarios that go over a threshold temp in an initial period, but then are brought back down to below the threshold in later years.
