Weather isn’t happening the way it did. We didn’t think it was possible, but air from the northern hemisphere is jumping the equator. That didn’t happen before. The tropics acted as a barrier between the hemispheres. Air from the north heading south and air from the south heading north were turned at the tropics and recirculated towards the poles. Now, lobes of air are breaching the border. The most likely cause is the dramatic warming of the poles. When the poles were colder there was a steeper temperature gradient between them and the tropics making it easier for the air to flow between them. Now, the poles are warming twice as quickly as the rest of the planet, reducing the gradient. The result is more of a tendency for the hemispheres to exchange air, effectively exchanging seasons. The seasons will continue to be driven by the Earth’s tilt, but pockets of weather are now more likely to mix summer with winter and winter with summer. Climate change is more than rising temperatures and rising seas; evidently, it will also be shifting and interrupting growing seasons chaotically. Planning for food production just became much more difficult.
(Click on the map for the link.)