Cyclone mitigation encompasses the actions and planning taken before a tropical cyclone strikes to mitigate damage and injury from the storm. Knowledge of tropical cyclone impacts on an area help plan for future possibilities. Preparedness may involve preparations made by individuals as well as centralized efforts by governments or other organizations. Tracking storms during the tropical cyclone season helps individuals know current threats. Regional Specialized Meteorological Centers and Tropical Cyclone Warning Centers provide current information and forecasts to help individuals make the best decision possible.
Tropical cyclones out at sea cause large waves, heavy rain, flood and high winds, disrupting international shipping and, at times, causing shipwrecks.On land, strong winds can damage or destroy vehicles, buildings, bridges, and other outside objects, turning loose debris into deadly flying projectiles. The storm surge, or the increase in sea level due to the cyclone, is typically the worst effect from landfalling tropical cyclones, historically resulting in 90% of tropical cyclone deaths. The broad rotation of a landfalling tropical cyclone, and vertical wind shear at its periphery, spawns tornadoes. Tornadoes can also be spawned as a result of eyewall mesovortices, which persist until landfall.
Over the past two centuries, tropical cyclones have been responsible for the deaths of about 1.9 million people worldwide. Large areas of standing water caused by flooding lead to infection, as well as contributing to mosquito-borne illnesses. Crowded evacuees in shelters increase the risk of disease propagation. Tropical cyclones significantly interrupt infrastructure, leading to power outages, bridge destruction, and the hampering of reconstruction efforts. On average, the Gulf and east coasts of the United States suffer approximately US$5 billion (1995 US $) in cyclone damage every year. The majority (83%) of tropical cyclone damage is caused by severe hurricanes, category 3 or greater. However, category 3 or greater hurricanes only account for about one-fifth of cyclones that make landfall every year.
Although cyclones take an enormous toll in lives and personal property, they may be important factors in the precipitation regimes of places they impact, as they may bring much-needed precipitation to otherwise dry regions.Tropical cyclones also help maintain the global heat balance by moving warm, moist tropical air to the middle latitudes and polar regions, and by regulating the thermohaline circulation through upwelling. The storm surge and winds of hurricanes may be destructive to human-made structures, but they also stir up the waters of coastal estuaries, which are typically important fish breeding locales. Tropical cyclone destruction spurs redevelopment, greatly increasing local property values.
When hurricanes surge upon shore from the ocean, salt is introduced to many freshwater areas and raises the salinity levels too high for some habitats to withstand. Some are able to cope with the salt and recycle it back into the ocean, but others can not release the extra surface water quickly enough or do not have a large enough freshwater source to replace it. Because of this, some species of plants and vegetation die due to the excess salt.In addition, hurricanes can carry toxins and acids onto shore when they make landfall. The flood water can pick up the toxins from different spills and contaminate the land that it passes over. The toxins are very harmful to the people and animals in the area, as well as the environment around them. The flooding water can also spark many dangerous oil spills.
Recent windstorm activity, in the United States in particular[ citation needed ], has focused interest in measures that can be used to lower the likelihood of damage to structures. Billions of dollars of damages have resulted from such strong winds and the manner in which structures have been built in the affected areas in the United States. Some building codes address mitigation measures. For example, the Florida Building Code, specifies the type of nail used to secure roof sheathing. The specification was determined by scientific research conducted by Florida International University's International Hurricane Research Center.
There have been many lessons learned about individual preparedness since Hurricane Katrina. The biggest responsibility was helping the children of New Orleans. Supplies were sufficient until there was more damage than the hospitals were prepared for. People were afraid that their safety was in danger due to lack of security and support at hospitals.
An important decision in individual preparedness is determining if and when to evacuate an area that will be affected by a tropical cyclone.Tropical cyclone tracking charts allow people to track ongoing systems to form their own opinions regarding where the storms are going and whether or not they need to prepare for the system being tracked, including possible evacuation. This continues to be encouraged by the National Oceanic and Atmospheric Administration and National Hurricane Center. Some agencies provide track storms in their immediate vicinity, while others cover entire ocean basins. One can choose to track one storm per map, use the map until the table is filled, or use one map per season. Some tracking charts have important contact information in case of an emergency or to locate nearby hurricane shelters. Tracking charts allow tropical cyclones to be better understood by the end user. If evacuation is not possible or necessary, other preparedness actions include storing supplies, securing a home against extreme winds and rain, and making plans with others prior to the storm's landfall.
Hurricane preparedness kits usually include drinkable water, sealed pre-prepared meals MRE, first-aid kits, prescription medications in sealed containers, waterproof battery-powered or hand-crank-powered flashlights and radios, a whistle or other sound-signaling device, a multi-tool with a knife, identification and medical cards, any necessary medical records, waterproof bags or portable waterproof containers, and other supplies helpful to a survival situation. If your pets will be with you make sure you include canned or dry food for them as well (any dry food included should be rotated every 2 months).You should also include veterinarian records and proof of vaccinations for all of your pets.
Preparedness also may include having discussed evacuation plans and routes, and informing others of those plans before a disaster occurs.
Evacuation to hurricane shelters is an option of last resort[ citation needed ]. Shelter space is first-come, first-served and only intended preserve human life. Buildings designated as shelters in Florida are required to only have been constructed to meet minimum code requirements applicable at the time of design[ citation needed ]. Some shelters are expected to protect occupants from wind and water but are not expected to provide food, water, sanitation, or bedding.
Based on preparedness of the people in a region, the preparedness level was greatly affected by the salary, race, age, etc. Many people are not prepared for the worst-case scenario, but they should be. Being prepared for a huge disaster is what will ultimately save your life if worse comes to worst.
Hospitals are needed to be prepared in advance for huge natural disasters. Nurses are in high demand when people are in trouble. They need to be prepared for ready for any situation that enters the hospital. After hurricanes such as Katrina and Rita, nurses are needed to be fully capable of any possible scenario.
An important decision a homeowner should make is to locate the building outside of range from the coast that is exposed to storm surge. Regardless of protection from the effects of wind, a building can be flooded or destroyed by storm surge waters.
To mitigate the effects of high winds and associated debris impact, the home can be examined out by an experienced hurricane mitigation professional. Many hurricane protection companies offer free consultations as part of their marketing strategy. The State of Florida has taken steps to help its homeowners in the area of hurricane preparedness through its My Safe Florida Home grant program. [ citation needed ]Qualified homeowners receive a free in-home assessment of their home's hurricane readiness. The state matches funds spent by the homeowner, up to a $5,000 limit.
When making these types of home improvements, there are two major areas of focus: the roof and the openings.
Homes may be retrofitted to withstand the extreme conditions of a tropical cyclone. Common modifications include reinforcing gabled roofs, applying additional adhesives to roof shingles, installing hurricane straps and clips to ensure the roof stays in place despite high winds.Hurricane resistant shutters, as well as impact resistant glass may help keep windows closed from driving rain, despite flying debris.
External patio and pool screen enclosures are especially vulnerable during a hurricane. A homeowner who anticipates sustained winds greater than 100 mph may use a razor knife taped to a telescopic pole to cut down the screens from the enclosure's skeleton structure. This will prevent the screens from acting as a sail and pulling down the entire enclosure structure.
Reinforcing garage doors and entry doors is also common practice for hurricane preparing a home.Garage doors may be protected by fabric screens, made of a strong woven fabric, to keep out projectiles and to reinforce the door.
The goal of these mitigation measures and products is to decrease the likelihood of severe damage to a home. There is no guarantee that these measures will safeguard any home against any kind of storm and the projectiles that may come with a storm, but a well-protected home is far more likely to come through a hurricane in better shape than a home that has little or no protection.
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Hurricane mitigation uses policies to make buildings and other infrastructure more resistant to the effects of tropical cyclones. In addition to facilities themselves being at risk, the internal contents of the structures can be damaged as result of exposure to water if the building envelope is breached, usually as a result of the strong winds associated with hurricanes and tropical storms. Although the negative pressure caused by high velocity wind flowing over a building roof can cause the roof to fail with the building envelope intact,broken windows allow the air pressure to rise inside a building, creating an even greater pressure difference, and increasing the likelihood of roof failure. This pressure increase results after an opening, that is, a window or door, is breached after being struck and broken by wind blown debris.
Few codes make the use of hurricane mitigation products mandatory[ citation needed ]. As the field is rather new to construction, few standards exist to address uniform testing or product certification of product installations[ citation needed ].
There is no single test standard or facility capable of qualifying the protection of an entire building. The Cyclone Testing Station 160 mph (260 km/h), and roof uplift simulation using suction tables per industry standards.in Australia can test building systems (e.g., roofs, exterior cladding), and indirectly test entire small buildings with structural loading to simulate wind pressures. In the United States, the test facilities at the FM Global Research Campus includes both direct wind testing of roof components to speeds up to
University of Florida's team led by Forrest Masters developed "the world's most powerful portable hurricane simulator, a giant machine capable of reproducing winds in excess of 120 mph (190 km/h) and recreating rain." It consists of eight large fans driven by four diesel engines, with a 5,000-gallon (19,000 litre) water tank to keep the engines cooled. The university is currently designing water-resistant windows, wind-proof tiles and altogether stronger structures.
This machine was used in the MythBusters 2009 season to test the myth that it's better to leave the windows open during a hurricane than closed (the myth was declared Busted).
The Saffir–Simpson hurricane wind scale (SSHWS), formerly the Saffir–Simpson hurricane scale (SSHS), classifies hurricanes – Western Hemisphere tropical cyclones – that exceed the intensities of tropical depressions and tropical storms – into five categories distinguished by the intensities of their sustained winds.
Hurricane Alicia was a small but powerful tropical cyclone that caused significant destruction in the Greater Houston area of Southeast Texas in August 1983. Although Alicia was a relatively small hurricane, its track over the rapidly growing metropolitan area contributed to its $3 billion damage toll, making it the costliest Atlantic hurricane at the time. Alicia spawned from a disturbance that originated from the tail-end of a cold front over the northern Gulf of Mexico in mid-August 1983. The cyclone was named on August 14 when it became a tropical storm, and the combination of weak steering currents and a conducive environment allowed Alicia to quickly intensify as it drifted slowly westward. On August 17, Alicia became a hurricane and continued to strengthen, topping out as a Category 3 major hurricane as it made landfall on the southwestern end of Galveston Island, Texas. Alicia's eye passed just west of Downtown Houston as the system accelerated northwestwards across East Texas; Alicia eventually weakened into a remnant area of low pressure over Oklahoma on August 20 before they were last noted on August 21 over eastern Nebraska.
Hurricane Camille was the second most intense tropical cyclone on record to strike the United States. The most intense storm of the 1969 Atlantic hurricane season, Camille originated as a tropical depression on August 14, south of Cuba, from a long-tracked tropical wave. Located in a favorable environment for strengthening, the storm quickly intensified into a Category 2 hurricane before striking the western part of Cuba on August 15. Emerging into the Gulf of Mexico, Camille underwent another period of rapid intensification and became a Category 5 hurricane the next day as it moved northward towards the Louisiana–Mississippi region. Despite weakening slightly on August 17, the hurricane quickly re-intensified back into a Category 5 hurricane before it made landfall a half-hour before midnight in Bay St. Louis, Mississippi. At peak intensity, the hurricane had a minimum pressure of 900 mbar (26.58 inHg). This was the second-lowest pressure recorded for a U.S. landfall, and is one of just four hurricanes to make landfall in the U.S at Category 5 status. Only the 1935 Labor Day hurricane had a lower pressure at landfall. As Camille pushed inland, it quickly weakened and was a tropical depression by the time it was over the Ohio Valley. Once it emerged offshore, Camille was able to restrengthen to a strong tropical storm, before it became extratropical on August 22. Camille was subsequently absorbed by a frontal storm over the North Atlantic on the same day.
Hurricane Betsy was an intense and destructive tropical cyclone that brought widespread damage to areas of Florida and the central United States Gulf Coast in September 1965. The storm's erratic nature, coupled with its intensity and minimized preparation time contributed to making Betsy the first tropical cyclone in the Atlantic basin to accrue at least $1 billion in damage. While the storm primarily affected areas of southern Florida and Louisiana, lesser effects were felt in the Bahamas and as far inland in the United States as the Ohio River Valley. Betsy began as a tropical depression north of French Guiana on August 27, and strengthened as it moved in a general northwesterly direction. After executing a slight anticyclonic loop north of the Bahamas, Betsy proceeded to move through areas of south Florida on September 8, causing extensive crop damage. After emerging into the Gulf of Mexico, the cyclone strengthened and reached its peak intensity equivalent to that of a Category 4 hurricane on September 10 before making its final landfall near Grand Isle, Louisiana, shortly thereafter. Once inland, Betsy was slow to weaken, and persisted for two more days before degenerating into an extratropical storm; these remnants lasted until September 13.
The 1979 Atlantic hurricane season was the first season to include both male and female names, as well as the common six-year rotating lists of tropical cyclone names. The season officially began on June 1, and lasted until November 30. These dates conventionally delimit the period of each year when most tropical cyclones form in the Atlantic basin. It was slightly below average, with nine systems reaching tropical storm intensity. The first system, an unnumbered tropical depression, developed north of Puerto Rico on June 9. Two days later, Tropical Depression One formed and produced severe flooding in Jamaica, with 40 deaths and about $27 million (1979 USD) in damage. Tropical Storm Ana caused minimal impact in the Lesser Antilles. Hurricane Bob spawned tornadoes and produced minor wind damage along the Gulf Coast of the United States, primarily in Louisiana, while the remnants caused flooding, especially in Indiana. Tropical Storm Claudette caused extensive flooding, due to torrential rainfall. There were two deaths and damaged totaled $750 million.
The 1981 Atlantic hurricane season was a fairly active season that featured 22 tropical depressions and twelve storms. The season officially began on June 1, 1981, and lasted until November 30, 1981. These dates conventionally delimit the period of each year when most tropical cyclones form in the Atlantic basin. Almost all of the named storms made landfall. Cindy, Harvey, and Irene did not affect land, either directly or indirectly.
Hurricane Charley was the first of four individual hurricanes to impact or strike Florida during 2004, along with Frances, Ivan and Jeanne, as well as one of the strongest hurricanes ever to strike the United States. It was the third named storm, the second hurricane, and the second major hurricane of the 2004 Atlantic hurricane season. Charley lasted from August 9 to 15, and at its peak intensity it attained 150 mph (240 km/h) winds, making it a strong Category 4 hurricane on the Saffir-Simpson Hurricane Scale. It made landfall in Southwest Florida at maximum strength, making it the strongest hurricane to hit the United States since Hurricane Andrew struck Florida in 1992 and the strongest hurricane to hit southwest Florida in recorded history.
Hurricane Frederic was an intense and damaging tropical cyclone that carved a path of damage from the Lesser Antilles to Quebec, in particular devastating areas of the United States Gulf Coast. Though only five were killed directly, the US$1.77 billion in damage accrued by Frederic made it the Atlantic basin's costliest tropical cyclone on record at the time. Prior to its final landfall, the threat that Frederic imposed on areas of the U.S. Gulf Coast triggered a mass exodus from the region larger than any other evacuation in the past. While the storm primarily impacted the U.S. states of Mississippi and Alabama, lesser effects were felt throughout the Greater and Lesser Antilles, as well as inland North America.
Hurricane Anita was a powerful Atlantic hurricane during an otherwise quiet 1977 Atlantic hurricane season. The first tropical cyclone of the season, Anita developed from a tropical wave on August 29 in the north-central Gulf of Mexico. It tracked westward into an area with conditions favorable for further development, and quickly intensified into a hurricane by late on August 30. Initially, Anita was forecast to strike Texas, though a building ridge turned it to the west-southwest. The hurricane rapidly strengthened to attain peak winds of 175 mph (280 km/h), and on September 2 Anita made landfall in eastern Tamaulipas as a Category 5 hurricane. It quickly weakened as it crossed Mexico, and after briefly redeveloping into a tropical depression in the eastern Pacific Ocean, Anita dissipated on September 4 to the south of the Baja California Peninsula.
Hurricane Kenna was the fourth-most intense tropical cyclone on record in the Eastern Pacific basin, and at the time the third-most intense Pacific hurricane to strike the west coast of Mexico. Kenna was the sixteenth tropical depression, thirteenth tropical storm, seventh hurricane, sixth major hurricane, and third Category 5 hurricane of the 2002 Pacific hurricane season. After forming on October 22 to the south of Mexico from a tropical wave, forecasters consistently predicted the storm to strengthen much less than it actually did. Moving into an area of favorable upper-level conditions and warm sea surface temperatures, Kenna quickly strengthened to reach peak winds of 165 mph (270 km/h) as a Category 5 hurricane, on October 25, while located about 255 mi (410 km) southwest of Puerto Vallarta, Jalisco. Weakening as it turned to the northeast, the hurricane made landfall near San Blas, Nayarit as a Category 4 hurricane, with sustained winds of 140 mph (220 km/h), before dissipating on October 26 over the Sierra Madre Occidental mountains.
Hurricane Rita was the most intense tropical cyclone on record in the Gulf of Mexico beating Hurricane Katrina and the fourth-most intense Atlantic hurricane ever recorded. Part of the record-breaking 2005 Atlantic hurricane season, which included three of the top ten most intense Atlantic hurricanes ever recorded, Rita was the seventeenth named storm, tenth hurricane, and fifth major hurricane of the 2005 season. Rita formed near The Bahamas from a tropical wave on September 18, 2005 that originally developed off the coast of West Africa. It moved westward, and after passing through the Florida Straits, Rita entered an environment of abnormally warm waters. Moving west-northwest, it rapidly intensified to reach peak winds of 180 mph (285 km/h), achieving Category 5 status on September 21st. However, it weakened to a Category 3 hurricane before making landfall in Johnson's Bayou, Louisiana, between Sabine Pass, Texas and Holly Beach, Louisiana, with winds of 115 mph (185 km/h). Rapidly weakening over land, Rita degenerated into a large low-pressure area over the lower Mississippi Valley by September 26th.
Hurricane Wilma was the most intense tropical cyclone ever recorded in the Atlantic basin, and the second-most intense tropical cyclone recorded in the Western Hemisphere, after Hurricane Patricia in 2015. Part of the record-breaking 2005 Atlantic hurricane season, which included three of the ten most intense Atlantic hurricanes ever, Wilma was the twenty-second storm, thirteenth hurricane, sixth major hurricane, fourth Category 5 hurricane, and the second-most destructive hurricane of the 2005 season. A tropical depression formed in the Caribbean Sea near Jamaica on October 15, headed westward, and intensified into a tropical storm two days later, which abruptly turned southward and was named Wilma. Wilma continued to strengthen, and eventually became a hurricane on October 18. Shortly thereafter, explosive intensification occurred, and in only 24 hours, Wilma became a Category 5 hurricane with wind speeds of 185 mph (298 km/h).
Hurricane Erin was the first hurricane to strike the United States since Hurricane Andrew in 1992. The fifth tropical cyclone, fifth named storm, and second hurricane of the unusually active 1995 Atlantic hurricane season, Erin developed from a tropical wave near the southeastern Bahamas on July 31. Moving northwestward, the cyclone intensified into a Category 1 hurricane on the Saffir–Simpson scale near Rum Cay about 24 hours later. After a brief jog to the north-northwest on August 1, Erin began moving to the west-northwest. The cyclone then moved over the northwestern Bahamas, including the Abaco Islands and Grand Bahama. Early on August 2, Erin made landfall near Vero Beach, Florida, with winds of 85 mph. The hurricane weakened while crossing the Florida peninsula and fell to tropical storm intensity before emerging into the Gulf of Mexico later that day.
The September 1948 Florida hurricane was the most intense tropical cyclone to make landfall in the state since the 1935 Labor Day hurricane. The fourth hurricane and third major hurricane of the season, this storm developed from a tropical wave over the Caribbean Sea on September 18. Early the next day, the system strengthened into a hurricane while moving westward passing close to Grand Cayman, Cayman Islands. Thereafter, it curved northwestward and continued to deepen. By September 20, the system turned northward and later that day made landfall in Zapata Peninsula, Cuba as a Category 3 hurricane on the modern day Saffir–Simpson hurricane wind scale. Another landfall occurred in Cuba early the next day to the south of Güines. Severe destruction was reported on the island, with winds up to 90 mph (140 km/h) observed in Havana. Over 700 buildings were destroyed. Ten deaths occurred and damage totaled at least $2 million (1948 USD), while other sources estimate "several million dollars."
The main effects of tropical cyclones include heavy rain, strong wind, large storm surges near landfall, and tornadoes. The destruction from a tropical cyclone, such as a hurricane or tropical storm, depends mainly on its intensity, its size, and its location. Tropical cyclones act to remove forest canopy as well as change the landscape near coastal areas, by moving and reshaping sand dunes and causing extensive erosion along the coast. Evenpoo well inland, heavy rainfall can lead to mudslides and landslides in mountainous areas. Their effects can be sensed over time by studying the concentration of the Oxygen-18 isotope within caves.
The effects of Hurricane Katrina in Florida were in both in the southern portion of the state and in the panhandle. After developing on August 23, Katrina made landfall near the border of Broward and Miami-Dade counties with 80 mph (130 km/h) winds on August 25. While it was crossing the state, the hurricane's convection was asymmetrical, primarily located to the south and east of the center. As a result, high rainfall totals occurred in the Miami area, peaking at 16.43 in (417 mm) in Perrine. The rains caused flooding, and the combination of rains and winds downed trees and power lines, leaving 1.45 million people without power. Damage in South Florida was estimated at $523 million (2005 USD), mostly as a result of crop damage. Further south, the hurricane spawned a tornado in the Florida Keys. In the island chain, Katrina dropped heavy rainfall and gusty winds.
The 1941 Florida hurricane was a compact but strong tropical cyclone that affected the Bahamas, Florida, and the southeastern United States in October 1941. The fifth known storm of the 1941 Atlantic hurricane season, it was first observed to the north of the Virgin Islands on October 3. The storm tracked generally westward, reaching peak winds of 120 miles per hour (193 km/h) before passing through the Bahamas. After weakening somewhat, the storm later passed across southern Florida with winds of 100 mph (161 km/h). The hurricane then emerged into the Gulf of Mexico as a tropical storm, but regained hurricane intensity and made another landfall along the Florida Panhandle. Turning northeast, it crossed Georgia and South Carolina, and entered the Atlantic Ocean on October 8.
The 1948 Miami hurricane(Air Weather Service designation: Fox) caused no fatalities in Florida, despite moving across the Miami area as a hurricane. The ninth tropical storm and fifth hurricane of the 1948 season, the storm developed from a large low pressure area over the northwestern Caribbean Sea on October 3. The storm intensified into a tropical storm early the next day and a hurricane several hours later. Fox then significantly deepened, peaking with winds of 125 mph (205 km/h) early on October 5. Around that time, Fox made landfall in eastern Pinar del Río Province of Cuba. Fox crossed the island and emerged into the Straits of Florida. Late on October 5, the hurricane struck Bahia Honda Key, Florida, with winds of 105 mph (165 km/h) and two hours later, hit Flamingo. Fox emerged into the Atlantic Ocean near Fort Lauderdale early on October 6. The storm moved northeastward and later curved to the east-northeast. Late on October 7, Fox made landfall on Bermuda with winds of 105 mph (165 km/h). Fox weakened over the next several days and later executed a large cyclonic loop. By October 16, it became extratropical while well east-southeast of Newfoundland.
Hurricane Andrew was a powerful and destructive Category 5 Atlantic hurricane that struck the Bahamas, Florida, and Louisiana in August 1992. It is the most destructive hurricane to ever hit Florida in terms of structures damaged or destroyed, and was the costliest in financial terms until Hurricane Irma surpassed it 25 years later. It was the strongest landfalling hurricane in decades and the costliest hurricane to make landfall anywhere in the United States, until it was surpassed by Katrina in 2005. In addition, Andrew is one of only four Category 5 hurricanes to make landfall in the United States, alongside the 1935 Labor Day hurricane, Hurricane Camille in 1969, and Hurricane Michael in 2018. Andrew caused major damage in the Bahamas and Louisiana, but the greatest impact was felt in South Florida, where the storm made landfall as a Category 5 hurricane, with 1-minute sustained wind speeds as high as 165 mph (266 km/h). Passing directly through the city of Homestead in Dade County, Andrew stripped many homes of all but their concrete foundations. In total, Andrew destroyed more than 63,500 houses, damaged more than 124,000 others, caused $27.3 billion in damage, and left 65 people dead.