As we await official word that 2014 was the warmest ever, global warming seems to be on hold in the eastern United States, thanks to an outbreak of arctic air.
The equatorial Pacific is warm enough for Decoded Science to declare an El Niño. And there’s weather news from Turkey and the Far East. Let’s go Around The World.
Arctic Air Outbreak in Central and Eastern US
It’s always there in the winter. Most of the time it minds its own business and covers Canada, making an occasional foray into the northern plains. But once in a while it gets up a head of steam and barrels through much of the eastern two-thirds of the United States.
We’re talking about cold, winter-time air that originates in central and northern Canada and Alaska. With little sunshine in this region, the earth radiating continuously, and the snow cover reflecting what little solar radiation there is, temperatures routinely fall to 40 degrees below zero (Fahrenheit).
The unleashing of the normally bottled-up cold air correlates with the position and orientation of the jet stream. The jet stream then, in turn, governs the position and intensity of the polar vortex. The polar vortex has generally bifurcated in the past couple of years, and last winter a lobe refused to budge from central North America.
The US experienced a return of the arctic air in November, but since then the vortex has behaved and December was warmer than normal. Now, it’s ba.a.a.a.ck — and with a vengeance.
Temperatures are already below zero in the northern plains and upper midwest, and they will get colder through Thursday. Dangerously cold temperatures will linger in the plains, midwest and northeast through the end of the week at least, as fresh surges of cold air plunge south.
The Weather and Flight QZ1801
We can blame the weather for many things, including some airplane crashes, but the AirAsia flight that went down between Indonesia and Singapore last week is not one of them. It’s clear that there was no excuse for this accident, and that human errors caused it:
- AirAsia did not have license for this flight. The airline was licensed to fly this route four days a week, but not on Sunday. How do air traffic controllers allow an unlicensed flight to take off?
- There was bad weather on the route, but many other planes traversed the area without trouble.
- No one transmitted the weather report, which clearly predicted strong thunderstorms, to the pilots.
An unlicensed plane with no weather briefing. Don’t blame the meteorologists.
Bad weather continues to hamper the search for bodies and black boxes. The crash area is in the intertropical convergence zone (ITCZ), an equatorial band of thunderstorms, which is especially active at the moment.
Western Drought Continues Despite Recent Rain
The recent rains connected with Extreme Weather Event Cucumber helped some, but much of California is still in extreme drought. Hopefully an El Niño will bring additional rain to the US southwest.
At the present time, there is a tug-of-war between simmering El Niño conditions (see below) and the anomalously high water temperatures over the Gulf of Alaska.
The former, El Niño, would bring a branch of the jet stream from the central Pacific into California; the latter, unusually high water temperatures, would cause high pressure over the west coast. This week, the Pacific Coast high is dominant and is coupled with the Canadian polar vortex to bring the cold weather to the eastern US.
Long range forecasts are ambiguous, so either side could be ascendant two weeks from now.
Another Snowstorm in Turkey
Decoded Science pointed out that the jet stream over Europe split in the fall, with a southern branch flowing across Italy and the rest of southern Europe.
Turkey has been particularly hard hit with storms, including one going on currently. Snowfall is exacerbated by a ‘Lake Effect’ from the Black Sea. As the saturated air hits the mountains of central Turkey, the uplift causes heavy snow.
Decoded Science Names El Niño Event Eggplant
The water in the equatorial Pacific Ocean is anomalously warm, and though the departure from normal and duration of the anomaly do not yet meet NOAA’s criteria for declaring an El Niño event, Decoded Science feels there’s no justification for the formal criteria. Proof is in the pudding, as they say, and the recent episode of the pineapple express (to continue the gastronomic metaphor) is just one instance of the effect the warm Pacific is having on weather around the world.
Australia has just experienced two record warm and very dry months, and this is another of the metrics that correlates with El Niño.
Decoded Science will have a full explanation of the current event Eggplant and its ramifications for weather in many parts of the world later this week.
Let’s Not Let Naming Winter Weather Events Get Out of Hand
In the last ten days, The Weather Channel has named three storms, none of which amounted to anything more than normal seasonal variations in snowfall. Decoded Science has been in favor of naming winter weather events for the purpose of accurate communication. But it serves no purpose to name every modest occurrence. At the rate The Weather Channel is going, they’ll be giving names to individual thunderstorms and snow squalls. They are beginning to justify the claims of critics who say TWC names winter storms just for publicity.
Decoded Science believes that extra-tropical weather cannot be defined precisely enough to provide the same kind of criteria for naming used in the case of tropical cyclones. We hope we can exercise good judgment in naming weather events that are either very unusual or affect a large number of people. El Niño Eggplant is already implicated in drought in Australia and record rain in California, so it meets these criteria.
Decoded Science invites TWC to engage in a discussion about standards for naming winter storms and other weather events.
How Are Record Cold Temperatures Related to Global Warming?
Climate change will involve more than just an increase in temperature. Models of the atmosphere indicate that more extreme weather will occur. The current cold spell is, therefore, consistent with global warming.
What changes in the weather do you see in your neighborhood?