This week’s brief but bitter cold snap over more than half the country prompted intense discussion about the polar vortex ranging from educational to bombastic.
|Figure 1: A depiction of the “average” polar vortex on Jan. 6. The winds of the vortex correspond to the narrow “rainbow” areas. The map is an average of the upper atmosphere’s “topography” (specifically, the 500 millibar height) from all the January 6ths between 1980 and 2010.|
|Figure 2: The polar vortex on Jan. 6, 2014. The ridge (“R”) and trough (“T”) responsible for relatively warm weather in much of the West and bitterly cold weather in the Midwest and East have been labeled.|
So let’s be clear: The cold snap this week was unusual but not entirely unprecedented. A few super-cold days don’t disprove global warming, just like a day of rain doesn’t end a drought. At the same time, we don’t yet know whether climate change will change the odds of future outbreaks of bitter cold. Research is still underway, and as of now, we shouldn’t necessarily expect these events to be more or less frequent in future winters.
Here’s a Q&A to cut through the hype:
- What is the polar vortex? The polar vortex describes the air circulating aloft (thousands of feet above the ground) about the North Pole, and its extent is marked by a ribbon of strong winds that is often called the “jet stream.” (We most commonly focus on the North Pole, but a similar circulation is present around the South Pole, too).
In the map (Figure 1), which is from the point of view of the North Pole, the vortex corresponds to purple and blue colored areas. The band where the colors change from blue/purple to red/yellow indicates the location of the jet stream, or the outer edge of the vortex. Winds are strongest where this color gradient is tightly packed (e.g., over the Pacific Ocean and North Atlantic Ocean). It tends to be quite cold at the surface below the purple areas, and warmer under the red/yellow areas.
It’s important to note that this figure is an average of many winter days. On any given day, we would see a number of deviations from this average pattern.
- What happened this week? Comparing this week (Figure 2) to the average picture (Figure 1), we can see that the purple area of the vortex has contorted and moved farther south. Along with this pattern, there are substantial “wiggles” in the jet stream. These deviations in the circulation helped bring cold air into the continental United States that normally stays in northern Canada and the Arctic. Meteorologists look for these wiggles, called “ridges” and “troughs” (“R” and “T” on the map) when putting together a forecast. While the trough brought notable cold to the Midwest and the East, the ridge has kept parts of the West warmer than average and relatively dry (much to the dismay of skiers).
Sales of electric vehicles (EVs) in the United States nearly doubled last year—and with consumer acceptance broadening, sticker prices dropping, new models on the way, and policy support growing, the outlook is even better for 2014.
In 2013, EVs increased their market share by 70 percent from 2012 levels, while all-vehicle sales grew 8 percent to reach a six-year high. Still, EV sales continue to lag forecasts made when these cars hit the market in late 2010, accounting for less than 1 percent of new light-duty vehicle sales. The strong growth in vehicle sales is mostly due to rising sales of gas-guzzling pickup trucks.
Optimism for EV market expansion is warranted, however, not only due to steady sales growth but also due to three key developments in 2013.
A recent "60 Minutes" story highlighted the demise of a few high-profile clean-tech companies that received federal funding. The story neglected to report why clean technology is vital to the future of our economy and environment in the first place, and therefore why it makes sense for the government to promote the development of wind and solar energy, electric vehicles, and other clean tech. Simply put, the goal is to transform our economy from one based on fossil fuels that emit heat-trapping gases to one based on clean energy that won't contribute to global climate change.
Private finance is playing a critical role in accelerating the deployment of clean energy technologies that will reduce the impacts of our energy use on the global climate. Can some of these innovative financing tools – or new tools – also help spur alternative fuel vehicles (AFVs) and fueling infrastructure?
That’s a question we have set out to answer in a new initiative with the National Association of State Energy Officials. As a first step, we’ve explored some of the key barriers in the AFV market that private investment could help address.
Happy New Year! It’s time to think about your resolutions for 2014. Consider making one that will result in a cleaner environment, a more stable climate … and a happier you. Here are a few ideas:
- Pledge to save energy. Take these actions to save money and energy, and leave the environment healthier for everyone in the New Year.
- Keep your gatherings food-waste free. Americans throw away 34 million tons of food every year. To reduce your waste, take what you know you’ll eat and make leftovers with any remaining food. Learn more in this blog.
- Compost it. Composting can be done in a pile in the yard, an outdoor bin, or even in a vermicompost (worm) bin indoors. You can build your own or purchase one online. Composting can help reduce the 1.3 billion tons of food that goes to waste globally and help reduce methane, a highly potent greenhouse gas.