Obviously, some of these methods are more likely to be successful in the wealthier countries. People continue to live in areas prone to tropical storms for a number of reasons. They may want to stay close to friends and family, or have jobs they cannot leave. Hazard perception is an important issue -- some people think they are safe and that the storms will never affect them.
In advanced countries there is often a feeling that the wealth and technology of the home country will deal with any disaster that hits. There is some evidence to support the theory that global climate change is leading to increased frequency of tropical storms around the world. Tropical storms Tropical storms are intense low-pressure weather systems that bring strong winds, heavy rainfall and storm surges to some parts of the world.
Impacts of tropical storms The primary impacts of tropical storms are: The immediate effects of strong winds, high rainfall and storm surges. Buildings and bridges can be destroyed, people can get into difficulties in the water, and roads and railways can become damaged. Power cables and telephone lines come down, crops are ruined, and water and sewage supplies are affected. MMWR, 42 4 Florida hurricanes in Telephone survey Not reported Physical injuries caused by the hurricanes were reported by 4.
Persons in flooded homes were 4. MMWR, 47 8 Florida hurricanes, Health facility Not reported Not reported Increased number of CO poisonings and hydrocarbon fuel exposures were observed in the post-storm periods.
Residents had a higher proportion of falls and motor vehicle accidents and a lower proportion of unintentional injuries as compared to relief workers. Injury rate of 4. In the 30 year period between and , approximately million people were affected by cyclones; The mortality estimate presented in this study is consistent with recent estimates in other studies 67 , but the numbers injured and displaced are likely gross underestimates given the low frequency with which these figures are reported.
Findings from the historical event review are also consistent with previous observations that cyclone mortality varies by region, economic development level, and event severity. Cyclone impacts were concentrated in the Asia-Pacific region and the majority of fatalities occurred in developing nations. The number of cyclones and deaths increased each decade but the average number of deaths per storm decreased.
Human vulnerability to cyclones will increase in future years due to population growth, urbanization, increased coastal settlement, poverty, and changing weather patterns which is associated with an increase in the number of high intensity cyclones.
A significant disparity between cyclone mortality in developing and developed nations persists, though apart from simple casualty counts there is little information available on the epidemiology of cyclone morbidity and mortality in less developed countries. This indicates a need for additional research outside of the US.
Additionally, the majority of high-fatality storms occurred in the latter half of the 20th century though no developed nation sustained more than deaths from a cyclone in this time period 67 , The leading explanations for regional differences in mortality is the size of the at risk population and the capacity for pre-event evacuation. Higher population densities in the Western Pacific and South East Asia where dense settlements in low lying areas are associated with increased risk of death in from storm surge 70 , A higher economic development among the countries in the Americas is associated with lower regional mortality rates because of increased capacity to evacuate.
Improvements in forecasting, and early warning systems and in evacuation and shelter procedures, particularly in developed countries, have reduced storm-surge related mortality and increased proportional morbidity and mortality in the post-impact period 16 , 19 , Findings of this review were contrary to the conclusions of other recent reviews which concluded that most storm-related mortality in developed countries occurs in the post-impact period In less developed countries females face a greater mortality risk 21 , An increased risk of death in younger 20 , 21 , 22 , and older populations 22 , 57 , 58 , 60 , was also observed which is consistent with broader natural disaster mortality trends.
However, it is important to note that primary research on cause and timeframe of death as well as demographic and other factors associated with increased mortality risk is limited almost completely to the United States. Future studies on the human impacts of cyclones should be focused in Southeast Asia and the Western Pacific, the regions where the majority of cyclone impacts occur.
While minimal data on cyclone-related injuries and mortality is available from less developed settings, it can be presumed that developing nations also bear the burden of cyclone-attributable injury where the frequency and severity of injuries are inversely related to degree of physical protection Minor trauma is common among the injured, including lacerations, abrasions and contusions, puncture wounds, and sprains and fractures 11 , 13 , 24 , 25 , 29 , 32 , 40 , 41 , 51 , 53 , 62 , The majority of those injured in cyclones can be treated on an outpatient basis and do not require sophisticated surgical or inpatient care 5 , Reported causes of death and injury in more developed countries during the post-impact phase include blunt trauma, vehicle accidents, carbon monoxide poisoning, burns and fires, electrocution, and chain-saw injuries.
As compared to needs for food, water, shelter, and sanitation, injuries are not usually a major public health problem in the post-impact phase 78 This suggests and that mobile field hospitals and specialized surgical teams may be ineffective responses and that non-medical relief may be a more appropriate strategy for morbidity and mortality reduction in the aftermath of cyclones 5. The availability and quality of data has likely increased and improved over time, however, in many events deaths, injuries, and affected population size are unknown or unrecorded.
For most events no data were reported for injured, displaced, and affected populations, contributing to underestimation of impacts. Inconsistencies and errors were common in data from different sources that called into question the reliability of available data. In some cases inclusion criteria and definitions were not ideal which created difficulties in reconciling event lists.
Challenges were encountered when modeling cyclone mortality including a non-normal distribution, which necessitated analysis with a categorical outcome. Information on GDP and GINI index were used for analysis regardless of the event year, but these values may have been different for events in the s.
When combined with uncertainty in the historical record and the relative paucity of primary research focusing on cyclone impacts in heavily affected Asian region, conclusions that can be drawn about cyclones impacts on human populations are limited.
Other principal limitations of the literature review are 1 that an in-depth quality analysis of all reviewed articles was not undertaken, and 2 the fact that only English language publications were included which likely contributed to incomplete coverage of studies published in other languages originating from low and middle income countries.
Analysis of the impact of cyclones on human populations is challenging given the paucity of data from the most affected regions, the occasional occurrence of extreme high mortality events, and the reporting inconsistencies including both lack of standardized definitions and temporal changes in collection procedures, completeness and accuracy of data.
However, even with this under-representation the impact of cyclones is huge, with million people affected, , deaths and , injuries were reported as a result of cyclones between and The primary cause of cyclone-related mortality in both developed and less developed countries was storm surge drowning.
In more developed countries an increased proportion of deaths and injuries were observed in the aftermath of cyclones as a result of improved early warning systems and evacuation. Male gender was associated with increased mortality risk in developed countries, whereas female gender was linked to higher mortality risk in less developed countries. Both older and younger population sub-groups also face an increased mortality risk.
Cyclones have significantly impacted populations in Southeast Asia, the Western Pacific, and the Americas regions over the past quarter of a century with less developed nations in Asia bearing the majority of the mortality and injury burden.
Additional preparedness and mitigation strategies, particularly in less developed countries where the majority of cyclones occur, can lessen the impact of future events. In particular, improvements in forecasting, early warning systems, evacuation and shelter procedures, and public education on safety precautions and post-impact hazards could reduce cyclone-related morbidity and mortality in future decades.
Fax: Email: sdoocy jhsph. Abstract Background. The funding body played no role in the design, writing or decision to publish this manuscript.
Introduction Tropical cyclones, also known as typhoons and hurricanes, have caused an estimated 1. Methods Data on the impact of cyclones were compiled using two methods, a historical review of cyclone events and a systematic literature review of publications relating to the human impacts of cyclones. Historical Event Review A historical database of significant cyclones from to mid was created from publicly available data. Accessed March 4, Tropical Cyclone Introduction.
September 1, Accessed November 29, Glossary of NHC Terms. June 17, Tropical Cyclone. American Meteorological Society: Glossary of Meteorology.
Accessed November 30, Noji, E. Public Health Issues in Disasters. Critical Care Medicine ;33 1 SS Natural disaster hotspots: a global risk analysis—synthesis report. Originally accessed May 24, with subsequent update on September 4, Accessed September to February for abstraction of storm event data.
Stata statistical software: release Human Development Report Mahajani AG. Darwin and cyclone Tracy. Christmas Ann R Coll Surg Engl. Morbidity of Hurricane Fredric. Ann Emerg Med. Siddique AK and Eusof A. Cyclone deaths in Bangladesh, May who was at risk. Trop Georg Med. Morbidity of Hurricane Elena. South Med J. Centers for Disease Control. Preliminary report: medical examiner reports of deaths associated with Hurricane Andrew—Florida, August Rahman MO and Bennish M.
Health related response to natural disasters: the case of the Bangladesh cyclone of Soc Sci Med. Risk factors for mortality in the Bangladesh cyclone of Bull World Health Organ.
The Bangladesh cyclone of why so many people died. Active morbidity surveillance after Hurricane Andrew—Florida, Hurricane-related emergency department visits in an inland area: an area of the public health impact of Hurricane Hugo in North Carolina. Hurricane Andrew-related injuries and illnesses, Louisiana, Deaths related to Hurricane Andrew in Florida and Louisiana, Int J Epidemiol.
Mortality of Kauai residents in the month period following Hurricane Iniki. Am J Epidemiol. Mortality from Hurricane Andrew. J Forensic Sci. Surveillance for injuries and illnesses and rapid health-needs assessment following Hurricanes Marilyn and Opal, September-October, Over the past 50 years, nearly one million people have died in tropical cyclones.
The cause is the increase in populations in exposed areas, due to the attraction of the sun in rich countries, population growth elsewhere. In developed countries, the loss of human lives has decreased significantly as a result of improved forecasts. But at the same time, the average cost of devastation has risen sharply. In terms of human lives, the most affected regions were Bangladesh with the two hurricanes of November and April , each claiming more than , lives, Honduras and Nicaragua with Mitch in October , Burma in with Nargis ravaging the Irrawaddy Delta, the Philippines with Hayan in , each causing tens of thousands of deaths.
Figure 2. Cleaning of the streets of Tegucigalpa after the landslides caused by Hurricane Mitch in October Within a radius of about km around the eye, the accumulated rain amount is about ten centimetres per day, but values five to ten times higher are not uncommon for intense events, and in certain regions such as the eye wall or on mountainous areas.
The arrival on land , whose surface is rougher than that of the ocean, causes a slowing of the wind and a strong convergence in the cyclone quadrant that approaches the coast. This makes upward movements more intense, accelerates moisture condensation and increases precipitation. In general, the eyewall weakens quite quickly after landfall.
On the other hand, the external bands are more resistant to this transition and are often responsible for heavy rains inland. Hurricane winds are among the most powerful on Earth. Only tornadoes produce stronger winds, but on smaller scales and for shorter periods of time.
The distribution of winds is rarely symmetrical: they are often more intense on the right resp. When a cyclone passes, debris of all sizes carried by the wind becomes projectiles that hit everything exposed. However, it is not the sustained winds that cause the most damage, but rather variations in intensity and direction that weaken the structures. Variability increases inland as topography generates small-scale a few kilometers and locally more intense circulations.
Figure 5. Ocean surface with white scum and spray trails under conditions of strong cyclonic winds. Its direction changes with the direction of the wind that rotates around the eye and, when the cyclone moves, it generates dangerous cross swells resulting from the superposition of waves generated by winds coming from different directions. This buffer zone, between the ocean and the atmosphere, plays an important role in the evolution of intense cyclones, reducing surface friction and limiting energy exchanges between the two environments.
Figure 6. Its amplitude is maximum on the right left of the displacement in the northern hemisphere south. It is 1 to 2 metres for light cyclones, but it can exceed 10 metres for the most powerful ones. Focusing by bathymetry and reflections from the coast can locally increase the amplitude of this exceptional tide.
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