The 2004 Hurricane Season in the Caribbean and the USA

A hurricane is a tropical cyclone that is found in the North Atlantic Ocean. Typically, they affect Central America, the Caribbean and the USA. Other tropical cyclones include cyclones in the Indian Ocean and the Bay of Bengal, and typhoons that affect Japan. Hurricanes are low-pressure systems that bring wind speeds of up to 300 kilometres per hour (typically 160 kilometres per hour) and up to 30–50 centimetres of rainfall. The 2004 hurricane season broke a number of records across the USA and the Caribbean as it brought more havoc than usual to affected areas. Its impact on countries varied, depending, in part, on their level of development and state of preparedness.

Hurricanes

Hurricanes or tropical cyclones are intense low-pressure systems, generally about 650 kilometres in diameter, that bring violent storms, high winds and sea surges to tropical and subtropical areas. They are also known as typhoons and affect a large proportion of the earth’s surface. Unlike temperate depressions (also known as cyclones) tropical cyclones are not associated with any fronts. Cyclones last for about a week – the intense low pressure causes strong winds, and raises sea level. Wind speeds of over 160 kilometres per hour are common. One definition of a tropical cyclone is that it has wind speeds of 32 metres per second or 63 knots per hour, and it develops in the tropics or subtropics. Tropical cyclones develop mostly in summer and autumn. They include a ring of intense wind surrounding a calm central eye. The eye, typically 12–50 kilometres wide, is cloudless with subsiding calm warm air. Around the eye, winds rotate anticlockwise and updraughts are very strong. Rainfall is intense – up to 200 centimetres per day.

The lowest recorded pressure was 876 mb in the northwest Pacific in 1975. Thus there is a rapid decline of pressure as a cyclone approaches, up to 18 mb in eight hours. The steep pressure gradient causes strong winds.

Figure 1.
A church being used as a hurricane shelter in Cavalla Hill, Montserrat.

Formation of a hurricane

A tropical hurricane has a life cycle of several days. In general, formation takes a few days while the core is still cool, then it takes one to two days while the core warms and pressure drops. Finally there are a few days of intensity, followed by a day or two while the hurricane dies. A number of factors are needed for the formation of the tropical cyclone:

· High sea surface temperatures (SST) of 27oC or more, hence tropical cyclones are found largely between 20o south and 30o north.

· Easterly waves.

· Significant Coriolis force is needed to deflect winds so that they rotate around a low pressure (thus cyclones occur beyond 5o of latitude).

· Ocean moisture is needed as a supply of latent heat.

· The troposphere needs to be free of high-level winds of great strength (they effectively remove the lid of the cyclone).

Cyclone tracks are difficult to predict. Nevertheless in the Northern Hemisphere they move away from the equator, travel westwards and then rotate and accelerate polewards. Once the air rises, it cools, and on reaching saturation releases huge quantities of latent heat. This provides the storm with its energy. Once a storm moves overland, it loses this source of energy. During the decaying stage, the cyclones decay for a number of reasons:

· They move inland, which results in a lack of moisture or latent heat as well as increased friction reducing wind action.

· They move into colder areas.

· The tropical cyclone remains stationary – cooling the sea beneath it.

· It moves into higher latitudes where the Coriolis force is increased – reducing the cyclonic spin relative to the ground.

· Fast, upper winds sheer off the top of the cyclone, thus uplift is reduced.

The 2004 hurricane season

There was considerable hurricane activity in the Caribbean and the USA in 2004. Four major hurricanes – Charley, Frances, Ivan and Jeanne – affected the region, causing upwards of 2,000 deaths. The accuracy and effectiveness of hurricane prediction and management varied considerably between the hurricanes and the countries affected by them.

Hurricane Charley

The initial estimate of the economic loss caused by Hurricane Charley on Florida’s Gulf Coast between 13 and 15 August was $25 billion (￡13 billion). The state's tourism and orange juice industries suffered incalculable harm and farmers faced long-term financial worries. President Bush authorised a $2 billion emergency-aid package. The storm killed twenty people in Florida and left thousands homeless. Several hospitals were badly damaged and entire counties were left without power. Charley became the second most expensive storm after Hurricane Andrew in 1992, and the fourth most expensive insured event after Andrew, the 9/11 attacks and the Los Angeles earthquake of 1994. After Hurricane Andrew, many insurers pulled out of providing hurricane cover to the affected areas and various government funds stepped in.

Hurricane Charley ruined 12,000 homes and caused billions of pounds worth of damage across much of west and central Florida. It was the worst hurricane to hit Florida for twelve years. Two million Floridians were advised to flee, in the largest peacetime evacuation. At least 27 lives were lost overall, including one person in Jamaica and several in Cuba. People died by being hit by falling trees, being flipped over in their trucks as they fled or electrocuted by fallen power cables. Up to 80 per cent of buildings in Charlotte County were damaged or destroyed. Over one million people in the state were left without power, and three Florida cities – Arcadia, Port Charlotte and Punta Gorda – were left entirely without water. Closed airports disrupted holiday travel at the peak of the season, which resulted in heavy losses for tourist businesses – even Disney World in Orlando was forced to close for a day.

Figure 2.
The Caribbean was severely affected by hurricanes in 2004.

In addition, there were changes to the physical landscape. Charley breached a spit, isolating North Captiva Island (the hooked end of the landform) from the mainland. The hurricane passed directly over North Captiva Island, resulting in a breach 450 metres wide. In southeast USA, most of the inlets cut through the barrier islands have been formed in a similar way, during previous hurricanes.

However, the hazard management was only partially successful. Charley landed much further south on Florida's Gulf Coast than predicted, affecting the many residents that had not been evacuated. Punta Gorda in Florida was officially declared a disaster zone, with estimates suggesting that the damage already runs into billions of dollars. Computer predictions were that the hurricane would strike land 1,190 miles to the north in Tampa.

The overall impact of Hurricane Charley was far greater than originally expected due to a range of factors, both physical and human:

· Magnitude – the hurricane was the strongest to hit Florida in twelve years.

· Prediction – half of the deaths were in Punta Gorda, a settlement of 15,000 people, where there was talk of lack of preparedness due to inaccurate predictions.

· Hurricanes are still not fully understood and they behave erratically, especially when the winds that drive them weaken.

Charley was the most devastating storm to hit Florida since Hurricane Andrew in 1992 but it was immediately followed by an even larger storm system, Hurricane Frances.

Frances

When Hurricane Frances struck in mid-August it was two to three times larger than Charley, and was predicted to be the worst hurricane to hit Florida for 50 years. It was the first time in more than a century that such high-intensity hurricanes have struck so close together.

As Hurricane Frances – 1,000 miles wide with winds of more than 120 mph – moved in on Florida’s east coast, forecasters warned that up to fifteen million people could be in its path. The storm swept through the Bahamas, ripping off roofs and uprooting trees. At least two people were killed. A school was destroyed by winds on Long Island and severe flooding was reported on Eleuthera, as up to 50 centimetres of rain fell.

After the inaccurate predictions of Charley’s course, emergency planners decided to take no chances. More than 2.5 million people left their homes for safe refuge along the 300-mile coast north from Miami as forecasters were unable to predict accurately where Frances would strike. It was the biggest evacuation in Florida's history. Even the Kennedy Space Center at Cape Canaveral was evacuated for the first time in its history, with all 14,000 workers sent home. By widening the evacuation area, forecasters could be more confident this time that there would not be a repeat of the loss of life caused by Charley.

The management of Frances had therefore been a greater success than Charley. Despite its size, only four deaths were reported in the USA. However, where the eye passed directly over the town of Stuart, it destroyed many buildings. Four neighbouring counties were declared a disaster zone, and four million people were left without power. Although Frances was a larger system than Charley, the wind speeds were actually lower. The storm’s intensity weakened from a category four hurricane to a category three. Much of the damage was caused by wide-scale flooding, rather than wind damage, as over 30 centimetres of rain fell across much of the state.

Some people did, however, benefit from the hurricanes coming together. As well as the $1 billion (￡550 million) windfall from Hurricane Charley that DIY chains were predicting, they were reporting further strong sales as nervous Floridians snapped up materials to protect their homes. But there was still more to cope with, as right after Hurricane Frances came Hurricane Ivan.

Figure 3. The causes of hurricanes.

Ivan

In early September, Hurricane Ivan ripped through a number of Caribbean islands before hitting the USA. The pressure at Ivan’s eye was the sixth lowest ever measured in the Atlantic Basin. Dozens more lost their lives as Ivan struck Barbados, Venezuela, the Dominican Republic, Jamaica, Cuba, the Cayman Islands and the US states of Florida and Alabama. The final death toll was estimated to be around 122.

Hurricane Ivan gusted with 155 mph winds and produced seven-metre waves when it struck the Cayman Islands, threatening the 45,000 inhabitants. Many islanders on Little Cayman were evacuated to the main island of Grand Cayman. On a third island, Cayman Brac, locals fled to caves that have traditionally been used as a haven against hurricanes.

Between 25 per cent and 50 per cent of the 15,000 homes on Grand Cayman suffered some damage. As it moved northwest across the Caribbean, Ivan sometimes reached category five, the top of the scale. There were unconfirmed reports of two deaths on the low-lying Grand Cayman, the largest of the group. Residents said parts of the island were under 2.5 metres of water. Many, if not all, buildings in the capital, George Town, suffered damage. Houses and businesses were flooded, an airport runway was submerged and roofs were torn off. All three islands were without electricity. A minor controversy later developed over whether reports of damages were under-played by the British government, fearful of disrupting tourism and flows of investment.

In Cuba, 1.3 million people were evacuated, 200,000 in Pinar del Rio province. The province, which grows the tobacco for Cuban cigars, was hit by hurricanes Isidore and Lili in 2002, which caused $40 million (￡22.27 million) of damage to the industry. Cuba is a Communist state with an authoritarian government. The police have the power to arrest people who fail to obey an evacuation order. Hence, the evacuation was successful. Cuba experienced no loss of life but saw serious damage to its tobacco crops.

In Jamaica, despite hurricane warnings, half a million stayed in their homes for fear of looting and burglary. As the clean-up operation got under way in Jamaica, almost the entire island lost its electricity and gangs of looters were reported to be roaming the streets of Kingston and Montego Bay. This example illustrates how important social and political differences between neighbouring countries can be in determining the impact of a natural hazard. And yet, Jamaica was lucky. On 12 September, Ivan was expected to make a direct hit on Jamaica. At the last minute, Ivan veered towards the south of Jamaica, rather than passing across the middle of the island. This reduced the final death toll to between twenty and 56, as the hurricane missed some of the most densely populated areas.

In its journey from the mid-Atlantic fringes of the Caribbean, Ivan devastated Grenada, killing 34 and damaging more than 90 per cent of the houses on the island, leaving 60,000 people homeless. Five people were reported dead in Venezuela and four in the Dominican Republic. In the Caribbean, Hurricane Ivan caused at least 70 deaths. The Red Cross said about ￡2.6 million was urgently required for basic needs.

Figure 4. Season of the storm.

Mexico began evacuating 12,000 residents and tourists from the eastern seaboard of the Yucatan peninsula in low-lying tourist areas around Cancun. World oil prices rose as companies operating in the Gulf of Mexico prepared for disruptions to gas and oil operations. Even Shell shut down productions in the gulf as a precaution and oil prices rose on fears that damage could lead to sustained reduced production.

When Ivan slammed into the USA on 16 September, it killed at least eighteen people and battered a broad swath of coastline from Louisiana to Florida with severe winds, torrential rain and waves as high as 8 metres. There were stories about the sewers backing up, and snakes and alligators emerging from them. Officials said that at least 1.7 million people living in mobile homes or in low-lying areas on the gulf coast of Florida were at risk. The worst of the storm hit the Alabama seaside resort of Gulf Shores. In Gulf Shores, flooding of up to 3 metres reached nearly a kilometre inland.
But the greatest number of casualties occurred in the Florida Panhandle, where tornadoes spawned by the hurricane killed at least thirteen people and washed away part of a road bridge. Thousands of tourists and conference-goers, including many from Britain, remained stranded in New Orleans.