As this cooling turn progresses, the ‘cold loop’ of the Jet Stream is getting colder. Folks on the US East Coast or elsewhere that a ‘warm loop’ from the tropics sits on your head are benefiting from the hot flow to the pole where the heat leaves. This does not mean that your area is “heating up”, just that the heat from the tropics is leaving by running over you… Here on the West Coast we are under the cold air headed south (to be warmed in the process of sucking heat out of the Tropics.)
This is, IMHO, a direct result of the sun going sleepy, having the UV drop off a cliff, and having the atmospheric height shorten. (All the steps are in evidence, only the proof of causality is ‘a work in progress’.)
We’ve already seen one example in the Snows Of Mount Hamilton that were here much later than in the last several decades. Now we have a “Winter Storm Warning” for Memorial Day up in the Sierra Nevada mountains. No, not unheard of, but just not all that common in the last few decades of an extra hot solar cycle.
Greater Lake Tahoe Area
Special Weather Statement
Statement as of 2:39 AM PDT on May 25, 2012
… Light snow accumulations possible in the Sierra and northeast
California through early Saturday morning…
An unseasonably cold low pressure system will is moving into the
Sierra today. This storm will produce snow across the higher
elevations of northeast California and the Lake Tahoe basin by
this morning… with additional snow showers through Saturday
During this time… several inches of snow will be possible in the
Tahoe basin above 7000 feet and in northeastern California above
6000 feet. Up to an inch of snow will be possible down to Lake
Tahoe level and between 5000-6000 feet in northeastern California.
Snow may accumulate on Road surfaces early this morning over
higher passes of the Sierra and again Friday night. Most Road
surfaces will be wet but slick patches will be possible above 5000
feet. Little to no accumulation is expected during the day on
roadways due the late may sun angle, despite the fact that it may
be snowing much of the day. By tonight… .some light accumulations
of snow are possible in the Lake Tahoe basin and highways
89… 49… 36… 44 and 299 in northeast California.
Although heavy snow accumulations are not expected… anyone
planning travel in the Sierra tonight or Saturday morning
should slow down and prepare for chain restrictions and possible
So about those mountain glaciers around the world… think snow in late May (and maybe even early June in some places) might make a difference?
So about those GHCN biases: Think having places like Tahoe IN the record in the baseline period and into the warm phase but OUT of the record now might, just maybe, be missing something important?
So about that 1200 km “fill in” done by GIStemp: Think calibrating it in the 1980’s and then using it in the 2010s-2020’s might just be giving fake warmer grid cells at altitude? Given that California had 4 GHCN thermometers in v2 (I’ve not checked v3 yet) and ALL of them were at the coast, I think “this matters”.
Here is an historical report for May 1982 ( 30 years or 1/2 cycle back) and the report for May 2012 so far. Notice that the scales are different, so the barometric pressure ‘wobble’ in 1982 is between narrower bounds. The present wind scale is shifted by a wind spike (that I suspect is bogus as it is hurricane type wind). Still, it HAS been more windy in this phase of the cycles. Notice the blue “wind gust” dots make regular “hats” on the wind pattern in 2012, while in 1982 there are just a couple of scattered dots.
IMHO the shift to much more wind that I first noted a couple of years back is a key feature of things. That it is entirely ignored by the Global Warming theories is, IMHO, a lethal omission. In the ’70s and ’80s there were many more incidents of aircraft turbulence injury and more crashes. Then in the ’90s and ’00s there were nearly none. Flying was typically very smooth and folks mostly got used to just not wearing seat belts while in flight. Since 1998 we’ve lost a couple of more aircraft and there have been a few reports of in flight injuries from turbulence. I think this anecdotal evidence indicates a fundamental change in air flow. There’s a lot more of it as the heat leaves.
It isn’t just a one month or weather event, either. We’ve got more gusts showing up all year long:
What does it all mean? Who knows.
My suspicion is just that the lowered atmospheric height comes with a stronger stratospheric flow and stronger decent of cold air at the polar vortex. This, then, shows up as a “loopy jet stream” as the Rossby Waves get deeper. It also shows up, IMHO, as a more ‘gusty’ wind paradigm and as faster air flows.
I’ve seen that pattern of more gusty winds in many graphs from different places. It isn’t just a Tahoe thing. I first noticed it in my own back yard. A tree that I look at every day through a picture window was spending much more time moving in the wind than in prior years.
Why does this matter? Well, pretty simply, fast moving air can transport more heat at the same temperature when compared to slow air. It is that whole “heat vs temperature” thing. The “Global Warming Climate Scientists” constantly harp on temperature when what really matters is heat flow. Any Engineer can tell you that moving more mass through a heat exchanger at a constant temperature moves more heat. Yes, eventually the temperature will shift to reflect the heat changes, but it is heat flow that is important in a calorimetry experiment.
Back in about the late ’50s and early ’60s I would watch the local (Chico California area) weather man do the weather reports. They would have a map of the Jet Stream up pretty much all the time and he would explain what was happening. We had great weather reports as it was Farm Country and it basically was THE major determinant of who would make money and who would not.
I got a brain full of those maps over time. They very frequently had a ‘loopy jet stream’. Then in the ’80s and ’90s the jet stream went more ‘flat’. That ‘flatter jet stream’ was not as interesting, and frankly the “nightly news” became infotainment and the nightly weather became the ‘nightly natural disaster’ report with little weather technology displayed. (A sad day…)
Is there an archive of the Jet Stream location over time? I don’t know. I’d love to have some analytical evidence for my assertion that we’ve shifted regimes from “loopy” to “flat” and back to “loopy”. (And then can connect it to winds historically; and on to precipitation and heat flow. EVENTUALLY having an impact on temperatures…) But other things are demanding attention at the moment. Still, I think that would be a very productive investigation of a 60 year pattern of linkages.
It ought to be possible to identify other areas under ‘equatorward’ Jet Stream Loops and find similar effects at altitude in their mountains. It ought, too, to be possible to find ‘polarward’ loops and find them warmer and wetter. As my ‘personal database of the mind’ is only stocked with North American Jet Stream maps, perhaps someone in Europe, Asia, South Africa, South America, Australia / New Zealand etc. can identify where they have ‘polarward’ vs ‘equatorward’ persistent loops.
Also remember that last year we even had springtime snow in the Los Angeles area. This isn’t just a one time one year fluke.
I think these will also map to historic periods of drought and flood, but haven’t had the time to get into the precipitation data. Still, when one area gets enhanced wet air from the tropics while an adjacent area gets drier colder area from the pole, it must change the precipitation. So, for example, does Eastern Australia get more rain now, but does Perth get a drought then? I just don’t know how the “loops” behave in the Southern Hemisphere…
But what I can say is that the cold air from “up north” is making it to California and the snows are returned to the mountains. Even on Memorial Day.