* The outline of hurricane Sandy
Hurricane Sandy was formed on October 22 and dissipated on October 31. Its highest winds throughout all the date was 110mph (175km/h) and the lowest pressure was 940hPa. The number of fatalities was 253 in all, and all costs of damage, at least, have risen to $65.6 billion. Affected areas by this hurricane expanded to wide range. This is Hurricane Sandy when it was near peak intensity on October 25. Firstly what is the hurricane? It is an intense tropical depression with a very strong rainstorm. Hurricane has the other different names, typhoon and cyclone, but these don’t have any of differences in terms of their characters, and the difference is only where it takes place. A hurricane is classified to five levels according to Saffir–Simpson hurricane scale based on the maximum wind speed within one minute.
According to the National Hurricane Center, its highest wind speed was 110mph, which mean Hurricane Sandy is classified to category 3. (More than Category 3 is distinguished as a record hurricane) Due to its climate, around the Southern Atlantic, there is likely to have a hurricane between June and November (especially between Aug and Oct), and U.S, as well as the West Indies countries has been suffered from its damage. From such a historical background, these countries have a strong feeling of prevention of damage by hurricanes. Particular in U.S, when hurricane Katrina strikes U.S, the government could not take adequate measure against a hurricane, and there was a great deal of damage. Since then, such a perception has been bigger and bigger among people. After the storm became a tropical cyclone on October 22, in case of Jamaica, the government called upon the all of citizens in the whole island to take precautions against the approaching tropical cyclone.
To begin with, how was it formed and how did it progress? At the first time, it began with a low pressure which is classified as a tropical depression on October 22 South of Kingston, Jamaica, and this tropical depression was named Tropical Storm Sandy at the same date. Firstly, it moved slowly because of a peak of the high atmospheric pressure called ridge. However early on October 24, the eye of hurricane started developing, and it headed for northward with steadily speed affected by the atmospheric trough. After that, the NHC (National Hurricane Centre in U.S.A) upgraded it to hurricane status and as of 19; 00 in Greenwich Mean Time that day, Sandy finally arrived at Kingston, Jamaica.
Then just after Sandy left from Cuba towards the northern sea, it rapidly intensified to winds of 110mph which is 175km/h although it had been 80mph (130km/h). After Sandy left Cuba, its structure became disorganised, and due to it, Sandy turned to the northwest over the Bahamas. By October 27, because of influence from an approaching trough, Sandy was no longer fully tropical depression. But after that, Sandy re-intensified into a hurricane from a tropical storm. Sandy’s second peak was on October 29, and it recorded 90mph (150km/h) and it had a wind diameter of over 1,000nautical miles (1,150 mi, 1850km). As of 2300 in Greenwich Mean Time on October 29, Sandy was not tropical, and an hour later, it made landfall on the south-west of Atlantic City with 90mph (150km/h) wind. On October 31, Hurricane Sandy finally dissipated over western Pennsylvania
This map shows the route of Hurricane Sandy.
Hurricane Sandy’s route was not usual as well. Most of tropical depression is likely to path into the sea in this season. However, in the case of hurricane Sandy, other high atmospheric pressure in the southern Greenland pushed it to side of inland. Now, why did it develop to one of the biggest hurricane on record? There has some of hypothesises, but most of experts say that there is a strong relationship between the global warming and its abnormal development. The sea surface temperature from Florida to Canada was 0,6℃ before the global warming had been identified, however since it has come up to the surface, its temperature increased by 2,4 ℃.
As the condition when a hurricane is created, at least, it requires three conditions. First, the ocean water must be warm enough to put heat and moisture into the overlying atmosphere to provide the potential fuel for the thermodynamic engine that a hurricane becomes. Second, atmospheric moisture from sea water evaporation must combine with the heat and energy to form the powerful engine needed to propel a hurricane. Third, a wind pattern must be near the ocean surface to spirals air inward.
In terms of hurricane’s mechanism, it still has a lot of unsure parts but as of today, it is found that hurricane’s initial energy source is the latent heat released by water vapor in the atmosphere on the tropical sea surface, which mean, as the temperature of surface of sea water increases, amount of vaporized water (primary energy source for a hurricane) also increases, and it is considered as the cause of Sandy’s unusual development. As I mentioned above, hurricane mechanism is still not made clear so it is not sure that whether or not only the global warming is the cause of occurring a massive scale of hurricane.
* Impacts on Jamaica.
Jamaica is also one of the region were has suffered from terrible damage by a hurricane Sandy. When hurricane sandy made landfall over south eastern Jamaica, the hurricane was still classified as category 1 with winds of 129km/h, and torrential rain was also hitting the country. In addition, because of its strong winds, a lot of trees were fallen and these blocked several roads, which made many communities inaccessible. Electricity and domestic water supply system was cut too. As a result, any of lifelines were temporary not available.
Not only public facilities but also a lot of houses were damaged by a strong wind (for example, the roofs were removed by the wind). In Portland and the area of Mount Pleasant 80% of roofs have been destroyed. Flooding also brought about in Pamphret and Port Maria and it made a lot of people evacuate to collective centers. Number of deaths was relatively less in spite of this scale of hurricane, but such an accident that one man was crushed by stones falling from a hillside and dead in a rural area near Kingston. The total cost of damage becomes $16.5 million throughout the country.
* Impacts on Haiti
Although Haiti was still recovering from 2010’s earthquake damage, a massive hurricane hit there. As of October 29, estimated 200,000 people became homeless because of heavy raining which went on four days. Port-Salut, where was given one of the worst effects by it, was damaged by over floated rivers, in addition, nation’s capital street, Port-au-Prince were also flooded by the heavy rains. Moreover, ongoing cholera epidemic was also warned due to unsanitary situation brought by flooding. The storm also ruined most of crops and as a United Nation said, as many as 1 million people in Haiti would face to food shortage problem unless enough aids would come.
* Impacts on U.S
The damage brought about by hurricane Sandy in the whole U.S was one of the most severe throughout all of U.S’s record. Eventually, the hurricane caused about ten billion dollar damage in the U.S. The total number of deaths raised to, at least, 131 in eight states and about 1000 houses were destroyed, so about millions of people left without electric service after the hurricane attacked. However, in comparison with Hurricane Katrina, total damage was considerably smaller. According to statistics, its differences are very clear.
For example, in terms of the number of deaths, it was over 1000 in the case of Hurricane Katrina, but in this time, the total number was ten times smaller than before. The number of displaced was also ten times smaller although Sandy’s diameter was bigger than Katrina and its total amount of rainfall was almost no differences. So, U.S’s countermeasure against hurricane has improved a lot compared with past examples. However, the other West Indians Countries are still developing countries regarding countermeasures.
http://www.huffingtonpost.com/2012/11/04/hurricane-sandy-vs-katrina-infographic_n_2072432.html http://www.skepticalscience.com/hurricane-sandy-global-warming.htm http://phillyecocity.com/act-philly/climate-act-philly/how-hurricane-sandy-is-related-to-climate-change/