Walked out the door this morning to a very pleasant 10° C breeze. It was only supposed to get up to 8° C today, so that’s a pretty good way to start the week.
It stays mostly warm and dry this week but with a chance of some drizzle today and tomorrow. It might clear up Thursday which means we could get below zero but overall we should stay quite mild during the day.
The reason for the warm weather is a ridge of high pressure setting up over top of us as you can see below.
You can see our barometer rising as the ridge builds in.
The green line shows we are currently at 102.5kPa and rising. The wind has also been steady for the past 24hr or so. Not super strong, but definitely persistent. There were plenty of tree branches down on the roads this morning.
This high pressure is causing the jetstream to bend up and over us again.
By Thursday it’s going to bend up even more.
As I’ve mentioned on this blog before, the “waviness” of the jetstream over the past few years has caused a whole new line of research by climatologists theorizing that the 75% decrease in Arctic sea ice, and faster Arctic warming than mid latitudes has caused changes in the jetstream, particularly in the October, November, December timeframe.
These changes, it is said, lead to the jetstream travelling further north (dragging warm up with it) and travelling further south (dragging cold air down like last week) and then lingering when it does (causing events like the Alberta and Toronto floods).
So is it true? Well if you want to see a fantastic debate between two scientists on this active area of research, I highly recommend reading the comments at this post at Cliff Mass’s weather blog in Seattle. This is real scientific debate that has gone far past whether global warming is happening or whether we are responsible, both agree on that, but rather how we are feeling the effects right now.
The debate is between Cliff Mass of the University of Washington, who believes there is no evidence of such a phenomenon occurring (based on recent research here). And Jennifer Francis, a graduate of UW and now at Rutgers University, who is a main proponent of this hypothesis and who points out that both hers, and the new research, show all of the effects expected, happening to the jetstream in that seasonal period.
So if you have made it this far, please do take the time to read Cliffs post from last week and the subsequent debate it sparked in the comments afterwards. It is very important, and enlightening, and at times entertaining, reading… At least for us weather geeks. 🙂