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What is a hurricane, typhoon, or tropical cyclone? (NOAA)

The terms "hurricane" and "typhoon" are regionally specific names for a strong "tropical cyclone". A tropical cyclone is the generic term for a non-frontal synoptic scale low-pressure system over tropical or sub-tropical waters with organized convection (i.e. thunderstorm activity) and definite cyclonic surface wind circulation (Holland 1993).

Tropical cyclones with maximum sustained surface winds of less than 17 m/s (34 kt, 39 mph) are called "tropical depressions" (This is not to be confused with the condition mid-latitude people get during a long, cold and grey winter wishing they could be closer to the equator ;-)). Once the tropical cyclone reaches winds of at least 17 m/s (34 kt, 39 mph) they are typically called a "tropical storm" and assigned a name. If winds reach 33 m/s (64 kt, 74 mph)), then they are called:

• "hurricane" (the North Atlantic Ocean, the Northeast Pacific Ocean east of the dateline, or the South Pacific Ocean east of 160E)
• "typhoon" (the Northwest Pacific Ocean west of the dateline)
• "severe tropical cyclone" (the Southwest Pacific Ocean west of 160E or Southeast Indian Ocean east of 90E)
• "severe cyclonic storm" (the North Indian Ocean)
• "tropical cyclone" (the Southwest Indian Ocean)

(Neumann 1993).

CyberFlight Into The Eye of a Hurricane (Air Force Hurricane Hunters, USAF 53rd WRS, www.hurricanehunters.com)

Welcome to the Hurricane Hunters! You're just in time... head across the hall to our auditorium, and join the crew for the pre-mission briefing. Then you can decide if you really want to do this!




You step out onto the flight line, and pause to catch your breath: it's a typical summer day on the Mississippi Gulf Coast. You see only three airplanes parked on the ramp, and your escort explains that of the ten aircraft owned by the 53rd WRS, one is flying Opal right now, and six have evacuated out of Opal's way. The others will evacuate later this evening.

As we fly over the Gulf of Mexico toward Opal, the weather is beautiful! It's an odd feeling, knowing that what awaits us is quite different. In Pilot Training, we were always told to stay far, far away from thunderstorms, now they want us to go right through them. We remind ourselves that we all volunteered for this job!

Hurricane Opal is nearly 300 miles away, so it will take only an hour and a half for us to get there. Do you want to now Hurricane Hunter flight deck or sleep until we get there.

After what seems like an eternity (was it really just three minutes?), the dark grey clouds outside the window begin to brighten, and suddenly blinding white light stings your eyes. The hiss of heavy rain shuts off in the same instant. One or two sharp bumps, and the plane flies smoothly again. You're not sure you've ever felt your heart pound so hard, but you survived...you're in the eye!

You fly another 105 nautical miles away from the eye to measure the extent of damaging winds in that quadrant of the storm, then turn to intercept the next inbound leg in the "Alpha pattern", which looks like a giant "X" crossing the storm. Less than two hours after the last time you penetrated the eye, you're there again! In fact, you'll penetrate the eye a total of four times on this flight, until the next Hurricane Hunter airplane is on its way to take over.



Thankfully, Opal weakened significantly before making landfall near Pensacola, Florida. She still caused $3 billion dollars in damage and nine U.S. deaths (most from falling trees). Even "minimal" hurricanes can wreak incredible destruction and must be taken seriously. Thanks for surviving your "Cyberflight Into the Eye"! We hope you enjoyed the trip--if you did, please tell your friends. We hope you'll accept this memento of your flight, a cyber-patch!!! Just point to the patch, "right-click" your mouse, save the gif file, and display it proudly on your computer...you earned it!

I Earned this lovely Hurricane Hunter Badge and so could YOU!

Experience the CyberFlight Through the Eye of a Hurricane yourself!

"The United States Hurricane Problem" (NOAA)

Population Growth

The United States has a significant hurricane problem. Our shorelines attract large numbers of people. From Maine to Texas, our coastline is filled with new homes, condominium towers, and cities built on sand waiting for the next storm to threaten its residents and their dreams.

There are now some 45 million permanent residents along the hurricane-prone coastline, and the population is still growing. The most rapid growth has been in the sunbelt from Texas through the Carolinas. Florida, where hurricanes are most frequent, leads the Nation in new residents. In addition to the permanent residents, the holiday, weekend, and vacation populations swell in some coastal areas 10- to 100-fold.

A large portion of the coastal areas with high population densities are subject to the inundation from the hurricane's storm surge that historically has caused the greatest loss of life and extreme property damage.

Perception of Risk

Over the past several years, the warning system has provided adequate time for people on the barrier islands and the immediate coastline to move inland when hurricanes have threatened. However, it is becoming more difficult to evacuate people from the barrier islands and other coastal areas because roads have not kept pace with the rapid population growth. The problem is further compounded by the fact that 80 to 9O percent of the population now living in hurricane-prone areas have never experienced the core of a "major" hurricane. Many of these people have been through weaker storms. The result is a false impression of a hurricane's damage potential. This often leads to complacency and delayed actions which could result in the loss of many lives.

Frequency of Hurricanes

During the 70's and 80's, major hurricanes striking the United States were less frequent than the previous three decades. With the tremendous increase in population along the high risk areas of our shorelines, we may not fare as well in the future. This will be especially true when hurricane activity inevitably returns to the frequencies experienced during the 40's through the 60's.

In the final analysis, the only real defense against hurricanes is the informed readiness of your community,your family, and YOU.