After the weather forecasters were way off their predictions for the last hurricane season (mercifully, thanking the sky-stream god), we have a renewed chit-chat weather concept to bounce around: Thermohaline Circulation...won't that make you sound smarty-alecky on your little bar stool!

Colorado State University’s Tropical Meteorology Project...recently released their closely watched forecast for 2014, which calls for just three hurricanes, with only one becoming a major storm reaching Category 3 or higher.
The annual forecast— followed by a handful of other expert predictions, including from the federal government — has become a kind of opening bell for the hurricane season, which begins June 1.

Technology and ever-improving computer models have dramatically improved the ability to forecast the path of storms once they have formed. But, as last year illustrated, there are still flaws in long-range, preseason predictions.

(An ex-pert) attributed the botched forecast to the dramatic weakening of a deep current called the Thermohaline Circulation, which carries denser, saltier water from the Earth’s polar oceans. When it is strong, more hurricanes tend to form.

The collapse of the current last year...was the biggest observed since 1950.
Making matters trickier is the inability to predict the current, which scientists describe as the ocean’s conveyor belt..."You can’t really see it until it’s happening. That’s the problem.”

Forecasters basically use two models to predict storms.
Gray and Klotzbach rely on historical data and statistics.
NOAA and Florida State create climate models, using existing sea temperatures and crunching more than 200,000 lines of computer code in the week leading up to the season to factor in atmospheric conditions such as wind speed, rainfall, sunlight and cloud cover across the globe, said Tim LaRow, an associate research scientist at FSU’s Center for Ocean-Atmospheric Prediction Studies...“It incorporates all the physical understanding that we have of the atmosphere,”...“And it gives us the equations of motion to calculate the flow of the air.”

In the six years...running the complex climate model — which NOAA’s Miami chief of hurricane specialists, James Franklin, described as one of the most reliable around — it has proved about 70 percent accurate.
But 2013 also foiled the model, even when he later ran it using actual conditions.

This year’s less-intense forecast stems largely from an expected El Niño — a recurrent global climate pattern — that has already started warming Pacific waters...An El Niño pattern generally produces stronger wind shear and fewer storms in the Atlantic.


Miami Herald/Wash Post Link:
www.washingtonpost.com/national/health-science/hurricane-predictions-were-off-la st-year-will-this-year-be-any-better/2014/04/21/a08e2590-c642-11e3-bf7a-be01a9b6 9cf1_story.html