Forecaster: Two phenomena responsible for world's bizarre weather
A graphic outlining sea temperature anomalies the first week in January shows drops in the Pacific as air temperatures rise between the U.S. and Europe (continents in gray). La Niña and the North Atlantic Oscillation are to blame, an expert says.
January 13th, 2011
03:35 PM ET

Forecaster: Two phenomena responsible for world's bizarre weather

The catastrophic weather events taking place across the globe – from Brazil’s and Australia’s flooding to the Eastern United States’ heavy snowfall – have two likely explanations.

Tony Barnston, lead forecaster at Columbia University’s International Research Institute for Climate and Society, said two phenomena – La Niña and the North Atlantic Oscillation – are likely responsible for the patterns we’re seeing.

Though La Niña is different every time, it can be simply defined as a drop in water temperature in the eastern and central tropical Pacific Ocean. This particular La Niña appeared in July, Barnston said, and will last through spring.

During La Niña, there is less rainfall in the tropical Pacific and a horseshoe pattern of warm water typically forms in the North Pacific, the coast of Southeast Asia and the seas around Indonesia and Australia (check out the graphic above).

In this case, though, “the whole globe looks to be compensating,” Barnston said, noting that it’s difficult to determine if  La Niña spawns individual weather events.

While Southeast Asia and Australia can typically expect warmer oceans and more rainfall during La Niña, the affected area stretches farther west this year and includes Sri Lanka and the southern tip of India, Barnston said.

There is presently a massive rescue operation under way in Sri Lanka to save victims of flooding that has already killed at least 13 people. Floods have killed another 40 people in the Philippines, and Australia has been inundated with deadly flooding reportedly estimated to cover an area the size of France and Germany combined. To the east of La Niña, South America's north coast has been slammed with rain, and hundreds have been killed in Brazil's flooding and mudslides.

La Niña usually means warmer temperatures in the United States, particularly the Southeast, but this year the North Atlantic Oscillation is trumping La Niña.

Since November, we have been in the negative phase of the North Atlantic Oscillation, Barnston said, meaning that air temperatures between the eastern U.S. and Europe will drop. This causes temperatures to rise in places like northeast Canada, Greenland and Iceland, as the mercury drops on thermometers in the eastern U.S.

Weather experts call it a see-saw pattern, and it will eventually affect water temperatures, though that’s a secondary effect, Barnston said.

So while La Niña would normally mean dryer, warmer weather for folks in the southern United States, “the North Atlantic Oscillation has superseded the La Niña” this year, bringing El Niño-like winter temperatures and snow to the Southeast, he said.

CNN meteorologists reported earlier this week that snow was present in every U.S. state but Florida.

Though La Nina typically lasts until April or May, the North Atlantic Oscillation can move from a negative to positive phase mid-winter. Barnston said the Southeast “could be warmer and dryer than normal later this year if the North Atlantic Oscillation ceases and desists.”

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Filed under: Australia • Brazil • India • Indonesia • Philippines • Sri Lanka • Tropical weather • U.S. • Weather • Winter weather
soundoff (963 Responses)
  1. Roland

    Hard to tell. Check bio fuel and algae fuel burned exhaust when it turned from liquid to gaseus state.

    January 14, 2011 at 1:47 am | Report abuse |
  2. Marley B

    The only thing bizarre about the situation in Brazil is building your house on the side of a muddy mountain and not expecting it to slide when it rains.

    January 14, 2011 at 1:49 am | Report abuse |
    • CaliForNia

      Yea, those darn crazy Brazilians... Why we would never do such silly things here!
      Oh, well apart from those crazy people in San Fransisco building an enormous metropolis on tectonic plate lines.. Oh and those fools in Los Angeles building their city in a giant bowl of jello like material...which really really works well during a quake.. or how about those idiots in Florida that continue building expensive homes on land that will soon be beneath the rising oceans? How about New Orleans? Oh and finally, if you love people building on those areas prone to mudslides....have you ever seen all the expensive homes in Laguna Beach...up on the canyon.. Did you see how well that worked out a couple of weeks ago.

      January 14, 2011 at 5:07 am | Report abuse |
  3. James

    It's obviously the end of the world. Next it'll be earthquakes and tsunamis followed by catastrophic weather changes. Seriously, didn't any of you watch 2012??? The signs are all here. Lol.

    January 14, 2011 at 2:01 am | Report abuse |
    • Arpad101

      One would have to be naive to believe in the crap about 2012.

      January 14, 2011 at 3:17 am | Report abuse |
  4. Mike

    There Is No 1 Cause To All Of This. Global Warming, Deforestation, Natural Disasters. The Truth Is That WE Are A Major Piece Of The Puzzle. If We Dont Learn How To Preserve This Planet. It Will Be Drastically Different In A Few Generations. The Future Is Always Changing. It Depends On OUR Actions.

    January 14, 2011 at 2:10 am | Report abuse |
  5. dtm

    So when all this happens Africa is not affected right!

    January 14, 2011 at 2:11 am | Report abuse |
  6. Man Clack

    Don't argue about The presence of God. God is there and God is real it just depends on yourself to believe. Who gives breathe?

    January 14, 2011 at 2:20 am | Report abuse |
  7. obviously

    Sarah Palin's causing it, of course.

    January 14, 2011 at 2:29 am | Report abuse |
    • Arpad101

      She can't notice global warming up there in Alaska.

      January 14, 2011 at 3:20 am | Report abuse |
  8. dtm

    Did I read someone's note saying there is no God! There is God and the devil. And that devil is you saying there is no God

    January 14, 2011 at 2:32 am | Report abuse |
    • At DTM

      I think the problem is that You believe in the Devil.. who then receives power from your belief...
      Its all your fault then!!

      You should join those of us who dont believe in the Devil, demons, leprechauns and faeries, werewolves and vampires. It makes for great scary movies or fun fantasy films... but it has only a basis in our imagination.
      And it has nothing to do with the weather.

      January 14, 2011 at 5:11 am | Report abuse |
  9. PraiseHim

    Praise Al Gore! The almighty bringer of tubes and monotone lullabies. We should have heeded his warnings, but it is not too late friends. Repent and be safe once again in his warming arms!

    January 14, 2011 at 2:34 am | Report abuse |
    • Arpad101

      Get out your hockey stick and skate on the ice but then it might be melting

      January 14, 2011 at 3:19 am | Report abuse |
  10. peta

    How about chemtrails and HAARP...

    January 14, 2011 at 3:08 am | Report abuse |
  11. Sally Li

    The truth is that we've never had such comprehensive knowledge of worldwide weather. These "unusual" patterns have always been with us – but we never had the technological ability to see these patterns on a worldwide basis, all at once, as they were happening. We only noticed them each in our own respective parts of the earth, without knowing what was going on anywhere else. To ignore this factor is to fall into the logical fallacy of believing that better reporting and collation of events necessarily means that more frequent occurrences have taken place.

    January 14, 2011 at 3:21 am | Report abuse |
    • Arpad101

      That is one of the most intelligent things I have heard here. You took the words right out of my mouth.

      January 14, 2011 at 3:48 am | Report abuse |
    • RUKEAL

      While technology affords us a far more accurate world view of weather and events, this does not mean that mankind of previous centuries were fools. The world of past centuries was not oblivious to these events and they are recorded in our history. News travelled slower (ship/train/horseback etc.) in those days but events were still reported. You'd have to be blind to not acknowledge that in the past few years there has been a spate of disasters, floods, tsunamis etc – 'Climate change'/'Global Warming' (whether man-made or not) would not exist as a theory/problem in our current lives if this unprecedented state of affairs was the norm.

      January 14, 2011 at 4:59 am | Report abuse |
    • Chris

      nice sally lee – level headed or what

      January 14, 2011 at 5:03 am | Report abuse |
  12. Ines

    Oh please...are we to believe this horse crap? The earth has it's cycles that go through thousands of years, we can't estimate or guess because we have only been recording climate for 100 years. The earth is billions of years old, and it's always going through climactic changes, stop using science as a measure or guess...mother earth is doing what it has been doing for thousands and billions of years period.

    January 14, 2011 at 3:26 am | Report abuse |
    • sssimon

      All those thousands of climate scientists did not know this. Thanks for pointing it out. I hope you get a Nobel Prize for you brilliant scientific work. [/sarcasm]

      January 14, 2011 at 12:32 pm | Report abuse |
  13. FstEti

    This Global Warm, uh Climate Change, touted by Liber, uh, Progressives, is the biggest scam since I convinced Cindy Lou to remove the snake that had fallen inside the front of my jeans......

    January 14, 2011 at 3:45 am | Report abuse |
  14. Tara

    What a pile of croc this article is. Wake up!

    January 14, 2011 at 4:03 am | Report abuse |
  15. charles

    ask the Mayans, might help lol. Can we say 2012? This is what they meant by 2012, mother earth is changing and we are seeing it now.

    January 14, 2011 at 4:19 am | Report abuse |
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