Topic 1 - Hazardous Environments Flashcards
What are 3 characteristics of TRS (Tropical Revolving Storms)?
High wind speeds, which cause large waves and storm surges
Heavy rainfall, which causes flooding
Thunderstorms
How are TRS distributed, and where do they form?
Between 5° and 30° north and south of the equator. Form over the oceans.
How are TRS measured?
Using the Saffir Simpson scale. This grades a storm from 1 to 5 based on its maximum sustained wind speed
What are 5 causes of a TRS?
Warm ocean temp - 26.5°C
Areas of low atmospheric pressure
Located between 5° and 30° north or south of the equator
Low wind shear
Coriolis force
How does a TRS form?
Hot air above the sea rises, spiralling up with the spin of the earth, raises the atmospheric temperature. This spiralling hot air forms into large, water full clouds. The clouds continue to spin with the spiralling winds below caused by wind rushing into low pressure areas where hot air has risen. As more clouds form, the clouds form cloud clusters, which combine and begin to spin faster and faster, as the clouds spin, as peaceful ‘eye’ is formed, where winds are lower, this allows cool air to descend back down through the eye, and these heat up and rise again, further fueling the hurricane, the strongest winds are just outside the eye, in the eyewall, on the edge of the storm, rainbands begin to form.
What are 5 social impacts of Typhoon Haiyan? Were they short-term or long-term?
- Killed 7500 people and affected 9 million people - Short-term
- 1.9 Million homeless and more than 6 million displaced in the affected Visayas region, housing crisis - Long term
- Due to a lack of food, clean water, shelter and medication, the UN fear the spread of disease - Short term
- Casualties were higher due to a lack of aid in affected areas - Short term
- The population in less affected areas were reportedly doubled with migrants - Long term
What are 6 economic impacts of Typhoon Haiyan? Are they short-term or long-term?
- Estimated $12-15bn damage - Long term
- Major rice and sugar production areas were destroyed in the Philippines - Short term
- 50,000-120,000 tons of sugar were lost
- The Filipino government estimated that 175,000 acres of farmland were affected; $85 million was lost from farm damage - Long term
- Coconuts account for nearly half of the Philippines’ agricultural exports, and it is the world’s largest producer of coconut oil, product lost and less trade - Long term
- 131,611 tons of rice was lost, a 1.8% reduction in fourth quarter output, 4,000 tons of corn was destroyed - Short term
What are 5 environmental impacts of Typhoon Haiyan? Are they short-term or long-term?
- Environmental damage and loss of forests, widespread flooding - Short term
- Oil and sewage leaked into local ecosystems - Long-term (Damage to animals)
- Lack of sanitation in the days following the event, higher levels of pollution - Short term
- Coconut plantations, which are a major source of income for the country, were ‘completely flattened’ - Long term
- Fishing communities were severely affected, boats and equipment were destroyed - Short term
What are 4 political impacts of Typhoon Haiyan? Are they short-term or long-term?
- The Philippines declared a state of national calamity and asked for international help just one day after Haiyan hit the country. - Short term
- President Benigno came under pressure to speed up the recovery and rescue operations, as well as provide resources - Short term
- The Tacloban City government was decimated, with just 70 workers directly after the disaster (2,500 normally). Many were killed, injured, lost family or too traumatised to work - Short term
- The UN admitted it’s response to the disaster had been too slow. - Short term
How are volcanoes distributed?
Volcanoes are concentrated along the edges of tectonic plates, particularly in areas with they collide or separate. They can also be above a hotspot.
What causes a volcano to erupt?
When magma rises and the buildup of pressure becomes too high, the magma will find cracks or weak points in the crust, usually at volcanoes, and it will erupt
Why do volcanoes form on plate boundaries?
The movement of the plates creates gaps for magma to rise up through and form a volcano
How are volcanic eruptions measured?
Using the Volcanic Explosivity Index (VEI). The index takes in the volume of products, eruption cloud height and other factors to give it a number. It is an open ended scale, with the largest eruptions in history getting an 8. A non-explosive eruption is given a 0.
What are 3 short-term impacts of the 2010 Iceland eruption?
- Over 500 farmers and their families had to be evacuated
- There was an 8-day travel ban over much of northern/eastern Europe. 107,000 flights (48% of total air traffic) were cancelled, affecting 10 million passengers
- Airlines lost an estimated £ 1.2 Bn in the 8-day travel ban
What are 3 long-term impacts of the 2010 Iceland eruption
- The ash contaminated local water supplies, and farmers had to bring their livestock indoors
- Large floods of water destroyed bridges and roads as they swept down the side of the mountain
- 20% of the Kenyan economy is based on the export of vegetables and cut flowers to Europe. Over 50,000 farmers were temporarily unemployed as their produce could not be sold; this loss of income affected them for much longer.
What happens at a conservative plate boundary? Will this cause earthquakes, volcanoes or both?
Two plates slide past each other, earthquakes can occur.
What happens at constructive (divergent) plate boundaries? Will this cause earthquakes, volcanoes or both?
Two plates pull away from each other, earthquakes and volcanoes can occur.
What happens at a convergent/destructive (collision) plate boundary? Will this cause earthquakes, volcanoes or both?
Two continental plates collide, pushing upwards and forming fold mountains. Earthquakes can occur.
What happens at a destructive (subduction) plate boundary? Will this cause earthquakes, volcanoes or both?
One oceanic plate subsducts (folds) under a continental plate. Earthquakes and volcanoes can occur.
How are earthquakes distributed?
Earthquakes occur along plate boundaries, as this is where a buildup of pressure can occur and be released, causing an earthquake.
What causes an earthquake?
The sudden release of a large buildup of pressure causes an earthquake, the pressure buildups because two plates get stuck/catch while sliding past eachother.
What are the two ways to measure an earthquake? How do these work?
- Richter scale - Measures earthquakes by their magnitude/strength. Each increase of 1 is ten times stronger than the previous (e.g. a magnitude 8.4 is ten times stronger than a 7.4). There is no upper limit, but the largest earthquake recorded was a 9.5, so it is thought of as a 1-10 scale.
- Mercalli scale - Measures earthquakes by how stong they feel to people and the impacts of the earthquake. It is measured 1-12, in Roman numerals (I-XII). Therefore, the same magnitude earthquake on the Richter scale could be worse than a higher magnitude earthquake on the Richter scale because it happened in a more populated area, and did more damage.
What are 5 ways to prepare for earthquakes?
- Education
- Planning
- Building design
- GIS
- Remote sensing
What are 3 ways to respond to an earthquake in the short term?
- Emergency aid
- Shelter
- Supplies
