https://earth.stanford.edu/news/polar-vortex-science-behind-cold#gs.t4z1tu

How do human activities affect the polar vortex?

AS: Increasing carbon dioxide in the atmosphere cools the polar stratosphere, which could increase the temperature difference between the pole and the equator and strengthen the polar vortex. There’s also some model evidence that the waves that are propagating upwards in the troposphere are getting more energetic as the planet warms, leading to a more perturbed polar stratosphere.


The polar vortex itself is not new, but it seems to be affecting weather on the surface every year now in a way that it didn’t in recent memory. What changed?

AS: The term “polar vortex” has been around since the late 1940s. It forms every winter and breaks up in the spring. But for the last 20 years or so, the polar vortex has been very, very disturbed in the middle of winter. Between 1989 and 1998, however, there were no split vortex events in midwinter. And if you look at polar vortex events starting in 1979, when satellite data begins, until now, the vortex either splits or becomes displaced on average only about once every other year.

We don’t understand what drives the variability of these events from decade to decade, but they’re definitely happening more frequently.

Bobby. wrote on Jul 31^st, 2019 at 6:38am:

I am sure Lee can with the aid of a graph or two.

I've done a search & found this:

https://www.wunderground.com/resources/climate/strato_cooling.asp

Greenhouse gases also cause stratospheric cooling

However, this recovery of the ozone layer is being delayed. A significant portion of the observed stratospheric cooling is also due to human-emitted greenhouse gases like carbon dioxide and methane. Climate models predict that if greenhouse gases are to blame for heating at the surface, compensating cooling must occur in the upper atmosphere. We need only look as far as our sister planet, Venus, to see the truth of this theory. Venus's atmosphere is 96.5% carbon dioxide, which has triggered a run-away greenhouse effect of truly hellish proportions. The average surface temperature on Venus is a very toasty 894 °F! However, Venus's upper atmosphere is a much colder than Earth's upper atmosphere. The explanation of this greenhouse gas-caused surface heating and upper air cooling is not simple, but good discussions can be found at Max Planck Institute for Chemistry and realclimate.org for those unafraid of radiative transfer theory. One way to think about the problem is that the amount of infrared heat energy radiated out to space by a planet is roughly equal to the amount of solar energy it receives from the sun. If the surface atmosphere warms, there must be compensating cooling elsewhere in the atmosphere in order to keep the amount of heat given off by the planet the same. As emissions of greenhouse gases continue to rise, their cooling effect on the stratosphere will increase. This will make recovery of the stratospheric ozone layer much slower.

Greenhouse gases cause cooling higher up, too

Greenhouse gases have also led to the cooling of the atmosphere at levels higher than the stratosphere. Over the past 30 years, the Earth's surface temperature has increased 0.2-0.4 °C, while the temperature in the mesosphere, about 50-80 km above ground, has cooled 5-10 °C (Beig et al., 2006). There is no appreciable cooling due to ozone destruction at these altitudes, so nearly all of this dramatic cooling is due to the addition of greenhouse gases to the atmosphere. Even greater cooling of 17 °C per decade has been observed high in the ionosphere, at 350 km altitude. This has affected the orbits of orbiting satellites, due to decreased drag, since the upper atmosphere has shrunk and moved closer to the surface (Lastovicka et al., 2006). The density of the air has declined 2-3% per decade the past 30 years at 350 km altitude. So, in a sense, the sky IS falling!

Johnnie wrote on Jul 31^st, 2019 at 6:55pm:

lee wrote on Jul 31^st, 2019 at 8:52pm:

So you got no graphs in relation to Bobbys question?

lee wrote on Jul 31^st, 2019 at 9:33pm:

I know about R744, we dodged bullet there.

So honey bunch, any graphs in the makings.

lee wrote on Jul 31^st, 2019 at 9:56pm:

Does wonders for the ozone.