Just how does this global warming work?
They say global warming. Right now in London its global freezing.
Here’s why Russia is experiencing a lot of snow and the role global warming may have.
? First is an event known as an Arctic Dipole Anomaly (AO), this is where the weather over the Arctic goes into reverse and feeds cold air down into Europe and North America.
Ordinarily Arctic weather is dominated by cyclonic conditions over Canada and anticyclonic conditions over Russia, this ensures a counter-clockwise rotation of air masses over the Arctic.
Because the Arctic is warming faster than anywhere else on the planet the temperature and pressure of the atmosphere has been disrupted leading to a full reversal of normal weather patterns. This had long been predicted as a consequence of global warming and first occurred in 2000. Since then there have been about a dozen further instances, including the current one.
The result is that places that are normally bitterly cold experience unusually mild weather, whereas the places which would be milder receive the cold weather; which is what’s happening now.
? The second factor is an event known as Sudden Stratospheric Warming (SSW), it’s thought that the AO is a contributory factor to this.
During the Polar Night the arctic receives no sunlight and the stratosphere cools significantly, down to as low as –80°C. Around the periphery of the supercooled air mass is the Polar Night Jet (PNJ) – an anticlockwise rotation of air currents some 40 to 50km above Earth’s surface.
In normal circumstances both the stratospheric PNJ and the tropospheric Arctic circulation move in an anticlockwise direction but during times of an AO the air masses are rotating in opposite directions.
The AO conditions disrupt the overhead PNJ causing the air mass to distort and the PNJ to deflect from it’s normal course. The PNJ weakens and in some cases can start flowing in a clockwise direction. As the winds weaken and the air-mass distorts it begins to break apart and collapse downward into the troposphere. As it descends it compresses and warms rapidly, by as much as 30°C in just one or two days. The air is still bitterly cold at around –50°C but is substantially warmer than it was.
As this mass of cold air collapses toward Earth is spreads out over the Arctic region and drives cold air into the surrounding areas. Like the AO, this brings unusually cold air to Canada, the northern US, Scandinavia, Siberia, Russia, northern Europe etc.
? The third factor is the Polar Jet Stream (PJS). This is a fast moving ribbon of air that circumnavigates the mid to high northerly latitudes close to the top of the troposphere and also in a counterclockwise direction.
The collapsing air-mass caused by a SSW and the movement of air away from the Arctic during an AO can push the PJS further south than it’s normal position.
The PJS acts as a barrier against the north-south and south-north movement of weather systems. It’s high northerly latitude keeps cold air to the north and milder air to the south, but as the PJS itself is pushed southward it no allows cold air to move further south than normal.
Additionally, the PJS is increasingly meeting opposing Rossby Waves – another type of wind phenomenon and one that is closely linked to global warming. This head on collision between the two wind systems causes deflection, slowing and stalling of the PJS and this can have massive implications on the weather in the northern hemisphere. It was just such events that significantly contributed to the US heatwave last year, the European heatwave of 2010, the devastating flooding in China in 2011 and in Pakistan in 2010.
The result is, as has long been predicted, that the overall temperatures will rise, snowfall will decrease and winters will become wetter and milder. But when we do get events such as an AO, a SSW, PJS disruption or a combination of these events (or all three as is happening now), we will see bitterly cold temperatures and very heavy snowfall.
And that’s how global warming can cause a “tsunami of snow”.
GLOBAL warming. Not 'Russian warming'.
Why concentrate on what happens on land? 72% of our planet's surface is water.
My point is that you keep trawling up articles on how X place is cold despite global 'warming' in order to try and make some sort sneering comment on the validity of the science.
Great pictures.
More fun than having a friend who knows how to read look up the word "global" for you in a dictionary.
no weather event can be connected directly with climate but weirder weather is exactly what should be expected when the underlying climate is changed. Did you expect normal weather with abnormal climate?
if you cannot understand this, ask the Australians about their drought.
Well Sagey, That was easy for Trevor to say but for us morons, what happened to all the CO2, do none of us believe in that any more. Not that I ever did?
The way you'd expect it to. More severe weather, more often.
DK
http://rt.com/news/winter-snow-russia-weather-275/
Just how does this global warming work?
