Tropical Storms and Hurricanes

Storm surges powered by tropical storms and hurricanes can wreak havoc along low-lying coasts. The settlers who founded New Orleans in 1718 along the lower Mississippi River experienced their first major flood the same year. Over time, many other floods have occurred in New Orleans and the lower reaches of the Mississippi, aided by the slow sinking of the floodplain as river sediments compact over time. 

The 53rd Weather Reconnaissance Squadron, known as the Hurricane Hunters of the Air Force Reserve, has been flying into tropical storms and hurricanes since 1944. The squadron s planes fly into the storms and send data directly to the National Hurricane Center by satellite. 

In our country there is a tropical climate with a high humidity and marine influence. Another significant aspect is the condition of island and our location in a region where the influence of cold fronts (north) and tropical storms and hurricanes (south) is received. 

The hurricane season in 2003 was extremely active in the basin of the Atlantic Ocean with sixteen tropical storms, seven hurricanes, and three super-hurricanes. Five of these tropical cyclones led to landslides in the northeast of Mexico. In 2003, destructive hurricanes devastated New Scotland and Bermuda. The formation of five tropical storms in the Gulf of Mexico turned out to be a specific feature of a region in the Atlantic Ocean. Three tropical storms formed outside the usual time interval (June-November), one formed in April, and two in December. In the eastern sector of the Pacific Ocean in the Northern Hemisphere, the activity of storm formation was below usual (there were no large-scale storms here at all). 

Cyclones (hurricanes/typhoons) develop over warm bodies of water and create high winds and thunderstorms. Many offshore oil and gas facilities, particularly in the Gulf of Mexico, are vulnerable to the effects of cyclones. Tropical storms and tropical depressions have the same causes as cyclones but generally do not generate such high winds—although they can create considerable rainfall. 

The hurricane began as a tropical depression on August 23, 2005, near the Bahamas. A tropical depression is characterized by surface winds blowing between 23 and 39 miles (37 and 63 km) per hour. By the next day, the tropical depression was upgraded to a tropical storm, an area with stronger winds and rain. It was given the name Katrina. The storm started moving toward the southeast coastline and did not officially become a hurricane until two hours before it struck land. 

Indices of losses caused by natural disasters depend much on the preparedness of the regional population to reduce the risk of losses. The heaviest losses are caused by floods and hurricanes. The spatial distribution of natural disasters is also non-uni-form (Table 7.16). For example, the percentage distribution of natural disasters by type and continent is as follows tropical storms 32%, floods 32%, earthquakes 12%, droughts 10%, other disasters 14% Asia 38%, America 26%, Africa 14%, Europe 14%, and Oceania 8%. 

Tropical storms, typhoons, or hurricanes, depending on their strength and geographical context, often deliver torrential rains. Increased river flow during such high intensity, low frequency rainfall events can transport a major portion of annual river N load to coastal systems. Historically, there has been a paucity of data on such events due to their irregular and extreme nature and the generally manual nature of water sample collection for nutrient analyses. However, with the use of in situ automatic water samplers and nutrient analysis systems, data from such events can now more readily be captured. 

The NWS issues warnings when hurricanes appear to be a threat to the US mainland, Puerto Rico, the Virgin Islands, Hawaii, and the Pacific Territories. As soon as conditions intensify to the tropical storm level even thongh thousands of miles from the mainland, the storm receives a name, and the Weather Service begins issning advisories. The advisories are issued every 3 h, or less, as it nears. Location, wind intensity, speed, and direction are given. As a hurricane moves toward the mainland, hurricane watch notices are issued. 

Announcement that hurricane conditions exist with sustained wind of 74 mph or higher and are possible within the specified interior area. Because hurricane preparedness activities become difficult once winds reach tropical storm force, the hurricane watch is issued 48 h in advance of the anticipated onset of tropical-storm-force winds. 

For coastal sites, the best protection is to use a dry site. To establish the reference level for such a site, the potential for coastal flooding has to be evaluated first. If the region of the site is subjected to tropical storm effects (typhoon, hurricane, cyclone) or if there is a history of tsunamis, historical data on the phenomena have to be collected. An analysis of available data can give a good indication of the maximum flood level at the site and, with an adequate margin, provides the minimum altitude for dry sites. Further guidance on a more sophisticated method is provided in Ref. [21]. 

Hurricanes predominantly effect the Gulf and Atlantic coasts of North America. These weather systems can also occur in other regions of the world where they may be identified by other names such as typhoons or tropical cyclones. Hurricanes that effect North America are spawned over the western Atlantic Ocean and usually develop between July and September. These weather systems are very powerful and can affect the weather pattern for hundreds of miles (kilometers) from the center of the storm. The National Weather Service can usually provide a 2-3 day warning to those areas in the expected path of a hurricane. 

Hurricanes are storms that develop when warm, moist air carried by trade winds rotates around a low-pressure eye . A large, rotating, low-pressure system accompanied by heavy precipitation and strong winds is called a tropical cyclone or is better known as a hurricane. In the Pacific region, a hurricane is called a typhoon. 

The National Centers for Environmental Prediction, part of the National Weather Service, oversees operations by several key specialized service oigani-zations run by professional meteorologists. The most important of these are the Hydrometeorological Prediction Center in Washington, D.C., the Tropical Prediction Center (includes the National Hurricane Center in Miami, Florida), and the Storm Prediction Center in Norman, Oklahoma, which maintains a constant tornado alert system for vulnerable gec raphical regions. Other operations include the Ocean Prediction Center, the Aviation Weather Center, the Climate Prediction Center, Environmental Modeling Center, and the Space Weather Prediction Center. 

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