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  • One of DNews' camerapeeps is going to the Caribbean, even though she KNOWS a hurricane

  • is bearing down right now!

  • How do we know storms are going to hit so far in advance?

  • Hope it doesn't ruin your vacay, Liz!

  • From a scientific perspective, hurricanes are amazing to behold.

  • They're raw, powerful nature in all its destructive glory.

  • But humanity's constructions and alterations to our environment don't hold up well to hundred-mile-per-hour

  • winds or the sea's violent encroachment onto the shore.

  • Hurricanes form when warm, moist tropical air rises, letting cooler air fall into the

  • now-low pressure area below.

  • As that heats, it rises too, letting more cool air move in...

  • Over time, this causes a cycling, swirling mass of air, pressure and wind that speeds

  • up before being thrown away from the tropics, sometimes in the direction of land.

  • Category 5 hurricanes, the most powerful storm on Earth, can create 155 mph (250kph) winds

  • and 19 plus foot (5.8M) surges of water called storm surge.

  • Needless to say, it helps to know they're coming so we can hightail it out of the way.

  • In 1937, a surprise hurricane hit New England and killed 600 people.

  • Before we could predict them, we had to learn how they formed and how to track them.

  • In the earliest days of hurricane prediction, the best we could do was fly out and meet

  • it.

  • Pilots literally flew toward a storm to learn more about them!

  • We've been flying INTO HURRICANES since 1943, when members of the Army Air Corps flew into

  • a hurricane off the coast of Texas sporting 132 mph winds (212kph).

  • These brave men learned about how hurricane air temperature changes from the edge of the

  • storm moving to the interior; and were able to track the storm on a path, laying a foundation

  • for the first hurricane warning predictions.

  • A year later, in 1944, pilots were able to get warning to New England and only 50 were

  • killed when a hurricane struck.

  • Hurricane prediction can save hundreds of lives!

  • Now in the 21st centurywith all this technology around uswe're still flying into storms.

  • IT'S STILL ONE OF THE BEST WAYS TO LEARN ABOUT THEM!

  • The Hurricane Hunters are part of the 53rd Weather Reconnaissance Squadron/403rd Wing

  • and they are the "only operational unit in the world flying weather reconnaissance on

  • a routine basis."

  • They provide surveillance of tropical storms and hurricanes all over the world and deliver

  • that information to the World Meteorological Association's Miami Regional Specialized Meteorological

  • Center or RSMC.

  • Today, the planes are equipped with more than just thermometersthey have data-gathering

  • tools to map winds and formations, and planes deploy "Dropwindsondes" throughout the storms

  • Dropwindsondes are expendable parachuted cylinders that measure "temperature, pressure, winds,

  • and humidity every half-second."

  • That information is supported by satellites from NASA, ocean buoys from NOAA and ground

  • stations and monitoring platforms spread across the Earth's continents, island and oceans.

  • All the data is relayed to the RSMCs in Miami, Honolulu, New Delhi, Tokyo, Nadi in the Pacific

  • and Launion (off the coast of Madagascar).

  • RSMCs are the front line for informing the public about any coming storms, but first,

  • we have to know what we're dealing with.

  • Once they have the data, scientists plug it into constantly revised and updated computer

  • models.

  • NOAA the National Oceanic and Atmospheric Administration has two supercomputers that

  • only run simulations of storms.

  • These computer models churn through all the new data and all past data to render the storms

  • in 3D and predict where they'll go and how strong they'll be.

  • Like with any science, as more data is gathered, the predictions get more accurate.

  • But even still, hurricane prediction is not an exact science.

  • Since 2003, predictions on hurricanes in the U.S. have been delivered 120 hours before

  • landfall, 96 hours before, 72, 48, 24, and 12.

  • At 120 hours before landfall (or five days out), the margin of error for where the storm

  • will actually hit can be 350 MILES (563km) off!

  • 350 mile margin of error means they could evacuate New Orleans, only to have the hurricane

  • smack into Pensacola, Florida or East Texas!

  • That's a big difference.

  • By the last 24 hours, they've got it down to 100 mile error margin (160km) or less.

  • Predictions get more accurate as the hurricane gets closer, and more data is collected, but

  • bad predictions severely affect residents being forced to evacuate, and can cost lives,

  • and money.

  • The reason it's so hard, is because data can be flawed or incomplete, the flights couldn't

  • get to where the meteorologists needed, ocean monitoring buoys could be damaged, or a ground

  • station might be!

  • And still, sometimes, the satellites aren't good enough, or the computer models just aren't

  • accurate enough.

  • It's a constant battle to make prediction better, and to add to the arsenal NASA is

  • launching eight microsatellites to track global hurricanes and forecast their movements.

  • CYGNSS or the Cyclone Global Navigation Satellite System will work together, and with GPS satellites,

  • to measure winds and waves on the ocean surface, as well as surface and cloud temperatures,

  • heat radiation, ocean roughness and hurricane intensity, and also how temperatures move

  • WITHIN storms (called convective dynamics) -- just like those 1940s pilots.

  • CYGNSS will be ready before the 2017 hurricane season, which is good, because Earth's hurricanes

  • seem to be intensifying and becoming more common; so every little bit helps.

  • Thanks to this vast network of collaborating applied sciences, we know a hurricane is coming

  • many days in advance!

  • Which is a huge leap in only 70 years.

  • Thanks to these systems, scientists can monitor and inform the public about every tropical

  • cyclone, hurricane, and typhoon anywhere in the world.

One of DNews' camerapeeps is going to the Caribbean, even though she KNOWS a hurricane

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B1 中級 美國腔

我们如何知道飓风何时来临?(How Do We Know When Hurricanes Are Coming?)

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    joey joey 發佈於 2021 年 04 月 16 日
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