Does this explain the current cold winter?

Does it explain the current cold winter? It may do, it may not, there isn’t enough data yet to say with any degree of certainty.

The article is describing conditions known as an Arctic Dipole Anomaly or Arctic Oscillation (AO). Ordinarily the Arctic weather is governed by anticyclonic conditions (high pressure) over Siberia and this feeds air into the cyclonic (low pressure) system that dominates northern Canada. This circumpolar flow of air establishes predictable patterns over the Arctic with winds, ice-floes and ocean currents rotating in a clockwise direction.

During times of an AO the pattern is reversed. First the winds begin to rotate anticlockwise, these push ice away from the shorelines and into open water and then the Transpolar Drift Current (TD) begins to flow in the opposite direction. In turn this reverses the flow of the Barents and Beaufort Gyres. Think of them like three cogs in a row where the TD is in the middle, the direction the TD flows in determines the rotation of the gyres.

Up until 50 years ago there was a steady 10 to 11 million square kilometres of ice in the Arctic each summer but in recent years it has receded to about 6 million km² thus exposing large areas of water that would otherwise be covered by the ice.

http://www.flickr.com/photos/trevorandclaire/49959...

New ice reflects about 80% of incoming energy from the Sun, the dirty multiyear ice reflects about 50% but the ocean waters only reflect about 15%. Therefore there is a significant increase in the amount of heat energy being absorbed into the waters of the Arctic region. This creates something of a catch 22 situation in that the extra heat melts more ice which then allows more heat to be absorbed and so on.

To apply the numbers: Historically 13.5 million km² ice annual average, today it’s 11 million, therefore reflectance of 2.5 million km² has decreased from approx 65% to 15%. At an average of 342 Watts per square metre per year incoming solar radiation, the increased absorption is equivalent to 171 W/m²/yr over 2.5 trillion m², a total of 427.5 terawatts. This compares to Earth’s energy budget of 174 petawatts or an increase of approx 0.25%, enough in itself to cause some 0.085°C of warming on a global scale.

Whilst this oscillation is a new weather phenomenon, one that first manifested itself in 2001, it didn’t come as a surprise as such an event had long been predicted as a consequence of global warming. There have been four such episodes so far and the most pronounced and disruptive has been this years.

Early this year we had similar conditions, this kept Arctic ice-extent at very low levels, we began the year at a record low for 1st Jan. As the oscillation reversed there was a rapid build up of ice, such that by the end of April the ice-extent was at it’s greatest for that time of year for several years. Then the ice began melting at an extraordinary rate, so much so that in the space of just one month it had gone from a recent high to an all time low.

The rapid melting continued until 29th June when the Arctic weather patterns went into reverse, the rate of melt slowed significantly and as the weather oscillated back and forth there were periods of rapid melting followed by periods of stability, something that’s never been known to happen before.

http://www.flickr.com/photos/trevorandclaire/50056... (note: graphic was created on 19th Sept 2010).

The Arctic is still misbehaving and despite the fact that it’s winter, the sea-ice extent is less today than it was a week ago, something that never happens at this time of year. This next graphic is right up to date:

http://www.flickr.com/photos/trevorandclaire/52834...

What does it all mean? It means that the Arctic has gone haywire, there’s ice receding in winter, the ocean currents are moving in the opposite direction to what they should be, ice levels are at record lows and the temperature at the most northerly permanent settlement in the world (Alert on Ellesmere Island) is warmer than it is in Edinburgh. Currently minus 2°C in Alert and minus 6°C in Edinburgh, normally at this time of year it’s about minus 30°C in Alert and plus 4 in Edinburgh

http://www.weather-forecast.com/locations/alert2/m...

http://www.metoffice.gov.uk/weather/uk/observation...

http://en.wikipedia.org/wiki/Alert,_Nunavut#Climat...

http://en.wikipedia.org/wiki/Edinburgh#Climate

Could it be that the Thermohaline Circulatory system has been shut down by the millions upon millions of gallons of thick, gloopy oil that is still sitting in the Gulf of Mexico? The oil was never removed; it was simply dispersed under the surface with the help of obnoxious quantities of toxic Corexit.

http://www.youtube.com/watch?v=YUOLXiK9xxE&annotat...

If you check out the jet stream you'll observe that if your particular piece of real estate is north of the jet stream you'll have 'cold' weather. Here in Arizona, southern California and most of the US southwest we're south of the jet stream. Because of that our weather is unusually warm for December. What does this mean? Because of gradual climatic changes, the result of an historically and geologically more robust 'greenhouse effect', the jet stream is beginning to dip down further south while the top of this wave has moved further north. This is a new thing in the world of climate...at least in an historical time frame. As this wave meanders across the planet the effect is either unseasonal cold or warmth depending which side of this river of moving atmosphere you're on. This of course is only the Cliff Notes version; there's a whale of a lot of higher math involved as to why the jet stream has become so erratic. What is known is that the less heat energy radiated into space in a 24 hour period requires atmospheric changes to balance the heat and energy equation....the jet stream's apparent greater amplitude is a part of balancing act. Adding increasing amounts of CO2 to the atmosphere makes this balancing act increasingly more erratic and more difficult to track and/or predict. This is a situation with a lot of moving parts, all of them tending to create problems or opportunities depending on where you live on Planet Earth. To say 'it isn't happening' when ALL of the data and the science reflects the opposite is a form of foolishness that borders on the creepy. The climate is changing, human activity is the cause and it's going to continue until a climatic balance is reached. No Al Gore required!

The air born ash from the Iceland volcano contribute to the extreme cold by preventing

some of the Winter Sun's Radiation from hitting the Earth's surface. The unusual

movement of air may also be enhanced by differences in temperature between zones

where the ash cause dimming and zones where it is not.

Winters tend and rebound with lots of cold.

This was mentioned in a sort of roundabout way in the original article, but just to make it clear for those who missed it, this absence of sea ice is largely what caused the surprisingly high global anomaly for November.

http://data.giss.nasa.gov/gistemp/2010november/Tem...

Some may remember this being discussed here a little while back.

http://answers.yahoo.com/question/index;_ylt=AoFKx...

Firstly, the contributors to the global warming section of Y!A are always in flux, but there are many who stick to just this forum. During periods of different news events we see people drop by for a question and answer or two and then make their way back to where they normally are. In the past week we've seen a large influx on "non-natives" with news events but there is an alarming trend to be found.

Those who stop by and ask a question typically in support of AGW theory tend to come from the science and mathematics sections (such as yourself)

Those who stop by with an ignorant rant about snow disproving AGW typically come from the politics section.

Anyways, to answer your question, it certainly seems that this could be a culprit for the unusual weather we're seeing around the globe. The climate is a complex system and radical man-made changes to the climate are going to have myriad effects. The false idea that global warming is going to lead to a conversion of temperate climates into tropical ones is 100% incorrect and seems to be held only by those who haven't taken a minute of time to actually understand the basis for AGW theory and the various effects it will have.

I give this question a thumbs up!

EDIT: Is this Paul B? Did you change your screen name? Am I just now catching on to this? I should have picked up on that with the way you give a link twice.

Personally I believe that, the earth is feeling the rising heat of the sun and is making every attempt to cool itself down. Covering the world in snow would help.

Wow! Talk about your cognitive dissonance. It reminds me of the justification for Antarctic cooling before the Steig et al paper came out. Antarctica was cooling but it was exactly what the models predicted. But when Steig came out with his paper that (wrongly) showed Antarctic warming, you turn around and said you see we were right. You want to have all of your bases covered. It does not matter if it is warming or cooling. It is due to global warming.

Thanks for that, both as a answer to the daft questions this cold weather brings, and a reassurance that we're not losing the gulf stream just yet!