Radiation From Fukushima Would Take 7 Days To Reach U.S
March 15, 2011 Leave a comment
“You can calculate how long the release of a radiation would take to cross the Pacific from Japan to the U.S. by choosing different speeds that the radioactive particles might be moving and using the direct distance between given locations- say Sendai, Japan, and Seattle, Wash.,” according to Expert Senior Global Meteorologist Jim Andrews.
However, even that calculation may not reflect how long the particle would take to cross the Pacific, since it would not likely cross the ocean in a direct path. This is the case because the wind flow is often a complicated pattern. A typical wind trajectory across the Pacific is westerly, since there is often a large dome of high pressure over the central Pacific and an area of low pressure in the Gulf of Alaska. Any storm systems moving across the Pacific would add kinks in the westerly flow that would make the path of a particle crossing the Pacific longer.
“In other words, it would be a very intricate and difficult calculation,” said Andrews.
On a local level, it is easier to break down the direction of the wind.
On Monday, the winds at the Fukushima power plant and the Onagawa power plant will generally be out of the north to northwest. So, the wind flow will still be directed offshore into the Pacific. This would be a protective wind that would blow most of the radiation out to sea. The wind direction will switch to an onshore direction Monday night into Tuesday, threatening to send the radiation toward the population.
“We are getting into the time of year where onshore winds occur most often,” said Andrews.
This is not good news, since an onshore direction would blow most of the radiation toward populated areas. An added threat is that with higher elevations just about 4 miles inland from the power plants, if a temperature inversion sets up in the atmosphere, radiation could be trapped. Authorities have warned residents to keep windows and doors closed and air-conditioning fans switched off to eliminate the intake of air from outside.
Calculated time for radioactive particles to cross the Pacific from the power plants in Japan to big West Coast cities if the particles take a direct path and move at a speed of 20 mph: Source
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