Friday, June 10, 2016
Words Best Left Unspoken
Ever notice how a word or phrase can abruptly disappear from our language almost without anyone noticing much less wondering why?
I wonder whatever happened to "tipping points"? Where did that term go? Why did it fall off the radar?
Just a few years ago, back when we thought tipping points were decades off in the future, we read about them a lot. We were told we had to keep manmade global warming increases to this limit or that if we didn't want to awake the Sleeping Giant of nature and trigger runaway global warming.
What we were doing was bad enough. It wasn't going to be easy getting by in a climate that was 2 degrees Celsius hotter. That kind of man made warming would be awful but it was at least survivable, not like what awaited us from far greater warming resulting from natural feedback loops triggered should we cross these invisible, unknowable lines called "tipping points."
I suppose tipping points are a bit like a blind man parallel parking. That's why we had to be very, very conservative. This was no time to be pushing our luck, testing limits.
The fact is there are signs, very obvious signs, that we've already crossed some major tipping points. Nature is now running with the ball and has a clear path to the end zone.
The most obvious of these is the Arctic sea ice. Just a few years ago the Inter-Governmental Panel on Climate Change (IPCC) was warning that, if we didn't mend our GHG emission ways, the Arctic could be ice free by the end of this century, 2100. End of the century. That gave us food for thought - tomorrow, maybe. Update: now we're looking at an ice free Arctic Ocean this year, probably, if not then next year for sure. Why did the IPCC get it so incredibly wrong? Easy, they were working on man made warming. What we're seeing today is nature's doing. We've crossed a major tipping point. Best we stop using that word, eh?
How about a new term, "Arctic amplification"? What it means is that the loss of reflective Arctic sea ice warms the ocean and the atmosphere which warms and energizes the Polar Jet Stream which accelerates the melting of the entire Greenland ice sheet and creates these things called Rossby Waves that brings polar air deep into southern latitudes and warmer southern air high into the Arctic that increases the polar melt and on and on and on.
Think of it as a progression: tipping point, change, knock-on effect, knock-on effect, knock-on effect, more change, knock-on effect, knock-on effect... you get the picture. It's called a "feedback loop" or a positive feedback loop to be exact. Positive in that it accelerates the process of change.
You can't see the Polar Jet Stream that's playing such an important role in this but you can see its handiwork, from space no less.
Yes, the Arctic is greening which is a good thing in some ways. Nice to see plants growing and migrating but nobody can be sure how this rapid ecological change will play out.
One downside is that our northern, Boreal Forest is browning, dying out. The changes underway will cause changes to precipitation, energy and carbon cycles across the far north.