- Oct 7, 2008
Zonal vs Meridional flow.
The entire atmospheric circulation in the Northern hemisphere is messed up because of climate change driven by high C02 levels and we continue to pump at record levels seriously messing with the Earth's climate and weather patterns are changing across the planet.
As a direct result of human induced climate change last couple of winters in North America have been brutally cold and many areas are experiencing their lowest temp ever recorded.
The current floods in the Adriatic and in UK are caused by a series of powerful cyclones steered south and towards the Mediterranean instead going over Scandinavia because of a persistent blocking patternt over Russia and well-established meridional flow.
In both Europe and the USA meridional flow dominates the weather for last couple of months.
In fact climate scientists have observed that last couple of years meridional flow dominates the weather during all seasons leading to unprecedented heat waves in summer and unprecedented cold waves in winter.
This is observed both in Europe and USA and to some extent in Asia.
High atmospheric C02 levels are clearly having a profound effect on Northern hemisphere jet stream making it weaker and more wavy allowing cold air from the North Pole to spill out towards the equator.
There is evidence that in Earth with lower atmospheric C02 levels the jet stream is stronger because there is a higher temperature gradient between the north pole and the equator. As a result zonal flow predominates in the mid-latitudes where most of human population lives and we have a relatively stable weather pattern with the seasonal changes we are all familiar with. A stronger jet stream keeps cold air tight around the pole.
In warmer climate temperatue gradient between the poles and the equator is reduced meridonal flow predominates during all seasons and hot air starts to invade and penetrate the poles while cold air spills out towards the equator.
In such scenario the jet stream weakens cyclones and anticylones often get stuck over an area for prolonged periods leading to historic heat waves in summer and historic cold in winter. Blocking weather patterns occur with increased frequency.
Stagnant conditions predominate in summer and winter, droughts and heat lasting months in Europe, USA and Asia will become more common as global warming intensifies.
From all of the above we can say with high certainty now that this pattern will contiue and winter 2019/2020 will be exceptionally cold in North America most likely one of the coldest in history.
Winter in Western and Southern Europe will be mild with increased flooding threat due to increased number of cyclones.
Scandinavia and European part of Russia will experience long periods of cold and snow throughout the season as a result of this same weather pattern.
Ontop of this a powerful sudden stratospheric warming event is expected to develop in the next couple of weeks and winds from Siberia will reverse and start to blow west towards Europe.
Comments and observations from your area welcome.