I have been saying how cold it is here in Southwestern Norway and that it is not usual. I've been expecting a lot of rain and strong winds, instead I get subzero temperatures, no wind, clear sunny skies and a lot of snow still on the grounds. Hmmm, what is going on? On TV, I hear news about the blizzards and snow in Northern Europe and also in Beijing, China. It is also very unusual for Beijing and the Chinese people there are not quite prepared for it. In Germany, I heard the news that some 9 homeless people have died, basically froze to death.
I don't really check on the weather patterms too much anymore because we are not sailing. Today, I decided to read up on what is causing this cold weather and more importantly, why people are caught unprepared for it. To me, the idea of living up north means it is cold! If somebody tells me "Alaska" - I think "cold, snow and igloos". Same with Norway - I would normally think "snow, cold and wind". But not apparently so. Yes, it is cold, but being in a coastal area, I really don't see much snow - not to the extent I see it now. Kjartan said that when he was young, it was like this - snow on the grounds until his birthday in March. Wow. That is 3 months too long for me.
Anyway, back to the "strange" phenomena". Here in the Atlantic ocean, there is a weather pattern called the North Atlantic Oscillation (NAO). The word "oscillation" denotes movement. So this NAO is actually what causes and determines the strength and movement of the wind. To make it simple from how I understand it, there is a difference in barometric pressures between the Icelandic LOW and the Azores HIGH. (Azores is a small country in the Atlantic ocean located west of Spain). The bigger the difference in pressures between that in Iceland and in Azores (positive NAO), the stronger the wind is from the west and Europe will experience wet and mild winters. If the difference in pressures is weak (negative NAO), the wind is very weak which then causes the arctic air from the north to be able to push and spill in southwards.
Based on the explanation above, I can then say we are in Negative NAO at the moment. This means the barometric pressure in Iceland and that in Azores is not that highly different. Below is the weather picture for today. I can see the low pressure system just above Iceland is 1008. Down in Azores, the high is at 1024. The difference is not that high, as compared to a low of, for example, 980, and a high of 1040.
I am not sure how they calculate the negative and positive NAO, but records show that this winter 2009/2010, there is a strong negative NAO between - 1.50 and - 2.10. The only winter months with a lower NAO index were February 1978 (-2.20) and January 1963 (-2.12). January 1963 was one of the coldest months on record in the UK and the Eastern US.
The wind is indeed very mild, and this is the reason the cold artic air from the north is spilling in to the south, all across Northern Europe, and from Russia into China.
There you go - that is the simple explanation for the "strange" weather up here. And NO - it is not because it is EL NINO year this year.
PS - The Viking sailors were the ones who first discovered the North Atlantic Oscillation pattern. Why do you think they were able to sail far far away and first discovered lands?