TEXAS, USA — You often hear that our planet is warming. In fact, we keep breaking records. But at the same time for the last two years, Texas has been hit by arctic blasts. So how can that happen?
Turns out we are still learning how a warming arctic affects the frequency and severity of cold spells in Texas.
When it comes to cold, there are several factors to monitor:
- The polar vortex (if it's strong or weak)
- El Nino or La Nina pattern (which can make us wetter or dryer than normal)
- Position of the jet stream
When the polar vortex is strong, it traps the cold air and keep it across the arctic. When it's weak, it can wobble and allow some of that cold air to be pushed to the jet stream.
And that's basically what happened the past two Februarys. You get that kink in the jet stream and arctic air is rushed across the central and southern parts of the country.
Recent research suggests the polar vortex is breaking down more frequently thanks to warming in the arctic. Melting ice leads to more water that absorbs the suns radiation. That accelerates warming in the Arctic which then disrupts the polar vortex and can lead to those kinks in the jet stream.
But more research needs to be done. Another argument is that the disruption of the polar vortex is just a natural variation. It will take more time to understand if those changes in the artic will lead to more February freezes in Texas.