Friday, December 09, 2016

Yes, Antarctic sea ice extent is at record lows right now for it's date, but its trend is still very much upward. Which lately some people (ie. Chris Mooney, who has been an exaggerating hyper-alarmist his entire career -- here for November -- while being utterly ignorant of basic physics) wants to overlook the long-term trend for short-term results. Don't we castigate deniers for the same every day of the year(?):

Maybe there is some tipping point. I haven't seen anyone explain that -- have you?

Otherwise Antarctic sea ice is going to have a statistically signifant positive trend for a very long time.


Unknown said...

Yeah the November 2016 Antarctic sea ice measurement looks impressive because it is only a month's worth of data and the scale is exaggerated. I think all it is saying is the melting started early compared to previous years, so we are seeing say the December measurement in November.

Unknown said...


JoeT said...

David, I think many have missed the big story here, which is that the decrease in Antarctic sea ice extent was pretty much expected by Meehl and co-workers due to the change in sign of the IPO. Here's the money quote as reported by Carbon Brief:

As for the future, evidence suggests that the IPO shifted to a positive phase in 2014, says Meehl: “In that case, we would expect the Antarctic sea ice expansion to slow and perhaps start shrinking a bit, depending on what the influences from the tropical Atlantic do.”

What's startling is that the shrinkage wasn't just 'a bit', but fairly dramatic. In this case I would conclude by saying that it is clear this has nothing to do with 'tipping points', that natural variability should not be underestimated and that trend analysis gives little insight into what is really going on.

Layzej said...

It looks like a flip of the IPO may also have implications for the rate of global surface temperature warming. - Initialized decadal prediction for transition to positive phase of the Interdecadal Pacific Oscillation (Meehl, Hu, & Teng)