Tropical Storms
5 main characteristics
1. To do with their direction of movement 2. To do with what they do when they move over land 3. To do with what is at the centre of the storm 4. To do with what surrounds the eye 5. To do with what happens at the storm's edge
Tropical storm loose strength on land
because their main source of power is the ocean
Eye
calmest part of the storm, low pressure, warm temperature
Edge of the storm
has higher pressure and temperature, less clouds, less wind and rain
Storm swirls clockwise
in the Northern Hemisphere
Storm swirl anticlockwise
in the Southern Hemisphere
Causes
large body of water over 27 degrees celsius for energy, swirling around low pressure eye, hot air from ocean surface and storm, thunderstorm, rising and cooling air
Characteristics of Tropical Storms
low pressure, dense clouds, calm eye, heavy rainfall, violent winds around edge of the eye,
Eye Wall
precipitation and wind greatest here, most intense rainfall
Tropical storm
weather system of very low pressure and hot air formed over tropical seas and involving strong wind and heavy rainfall
Vortex
Dense cloud, violent wind, torrential rain, thunderstorm
Strong winds
Destroy trees, crops, buildings, transport, power and communication
Heavy rain
Destroys farmlands, can cause landslides
Explain the distribution
Equator is between 2 tropics and is where the water is hottest. Tropical storms need water 27 degrees celsius or above to form.
Preparation
Evacuate - higher ground, emergency shelter Protect property Purchase provisions - food, water, medicine Homes made ready - board up windows, move furniture upstairs Media - keep everyone updated about storm
Distribution of Tropical Storms
Form between the Tropics of Capricorn and Cancer. Fairly evenly distributed between 2 tropics.
Cyclone Nargis
From April 27, 2008 to May 7, 2008. Warning: No early warning to vulnerable population. Cyclone hit densely populated area of Myanmar, river deltas are connected to the ocean, very vulnerable Myanmar is an LIC. Facts: Around 138,366 people killed, 1.5 million people left homeless, 10 billion dollars worth of damage, storm surge 40 km up Irrawaddy River, 165km/h highest wind speed, 6 meter high storm surge, lowest pressure to 962mbar, category 4 storm Effects: 75% of buildings collapsed, 1,163 temples destroyed, rice fields in Irrawaddy delta flooded, children orphaned, 50,000 people still missing Response: Military refused aid because they didn't want foreigners to come into the country and destabilising their political oppression. 6 days after the cyclone, Myanmar asked UN for help. It wasn't until 3 weeks after the storm that international workers where allowed to come into Myanmar and give aid.
Hurricane Katrina
From August 23, 2005 to August 31, 2005. Warning: National Hurricane Center in Florida issued Hurricane Watch 36 hours before landfall and Hurricane Warning 24 hours before landfall. People told to evacuate and secure property. America is an HIC. Effects: Flooding caused by storm surge and rainfall. Floods destroyed levees protecting cities. High winds blew down unstable buildings and trees. Oil facilities damaged, oil spills and petrol prices rose. Superdome crowded because so many people seeking refuge, violence broke out. Facts: Around 1,836 lives lost, category 5 hurricane, 174mph highest winds, 108 billion dollars in damage, 80% of New Orleans flooded, 6 foot high storm surge, 1 million people left homeless Response: FEMA provided housing assistance for 700,000 people, Congress authorised 62.3 billion dollars in aid, National Coast guard rescued 33,500 out of 60,000 stranded people
Why is a tropical storm's impact more severe on LIC?
HIC have more money so they can warn people earlier, educate their citizens, prepare for evacuation, better building infrastructure, recover more quickly, more shelters, more media coverage of storm. But HIC also have more people so possibly more deaths.
Perfect storm
High winds, huge storm surge, heavy rainfall, no preparation, LIC, little prediction
Storm surge
Huge waves hit land on coastal areas
Names for Tropical storms
Hurricanes - Atlantic Ocean Cyclones - Indian Ocean Typhoons - Pacific Ocean Wild Willies - Australasia
Factors affecting damage and destruction
Scale and Longevity - the energy of an event, the area it effects and how long it lasts Advance Warning - How much warning the population gets before the event Settlement Density - More people and economic activities means more damage Degree of Preparation - Are there shelters? Are people educated? Is building structure good? Located in low risk areas? The ability to cope with the aftermath - immediately and long term - depends on HIC or LIC
How do tropical storms form?
Start when strong thunderclouds drift over warm ocean waters. The very warm air from the storm and ocean surface combine to create low pressure. Trade winds blowing in opposite directions cause the storm to start spinning. Air rises faster to fill in the low pressure in the eye, drawing more and more warm air off the ocean, and sucking cooler, drier air downwards. Storm picks up more warm moist air as it moves across ocean. Wind speeds increase and air is sucked into low pressure centre.
3 main hazards
Torrential rain High wind (120mph+) Storm surge
How to collect weather data
Use radar and weather stations, meteorologists look at patterns to see what's coming. Use satellites that can see the storm from space to predict the path.