Hazards PDF

**Natural event:** Something happening in the physical environment such as a storm, volcanic eruption or earthquake **Natural hazard:** an event which threatens the well-being of people and their property **Natural disaster:** A natural event or natural hazard causing damage and destruction to pro...

**Natural event:** Something happening in the physical environment such as a storm, volcanic eruption or earthquake **Natural hazard:** an event which threatens the well-being of people and their property **Natural disaster:** A natural event or natural hazard causing damage and destruction to property, as well as personal injuries and death **[Tropical cyclones:]** - - 1. 2. 3. 4. 5. 6. **Conditions;** - - - - **Facts:** - - - - - - - - - - - - **How are tropical cyclones measured** - **Category** **Winds (kmph)** **Damage** **Storm surge (m)** -------------- ------------------ ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- --------------------- 1 74-95 **Minimal:** damage to unanchored mobile homes, vegetation and signs. Coastal road flooding. Some shallow flooding of susceptible homes. 4-5 2 96-110 **Moderate:** significant damage to mobile homes and trees. Significant flooding of roads near the coast and bay. 6-8 3 111-130 **Extensive:** structural damage to small buildings. Large trees down. Mobile homes largely destroyed. Widespread flooding near the coast and bay. 9-12 4 131-155 **Extreme:** most trees blown down. Structural damage to many buildings. Roof failure on small structures. Flooding extends far inland. Major damage to structures near shore 13-18 5 More than 155 **Catastrophic:** all trees blown down. Some complete building failures. Widespread roof failures. Flood damage to lower floors less than 15 feet above sea level. Greater than 18 **[Earthquakes]** - -  **Focus:** the point inside the crust where the pressure is released **Epicenter:** the area on the Earth's surface directly above the focus **Seismic waves:** waves of energy that travel through the Earth's layers **Earthquake:** an earthquake (aka quake tremor) is the shaking of the surface of the Earth, resulting from the sudden release of energy in the Earth's lithosphere that creates seismic waves **Seismic waves:** waves of energy that travel through the Earth's layers **[Richter scale]** - - - - - **[Mercalli scale]** - - - - - - - **[Volcanoes]** - 2.1.1 Main Features of Earthquakes & Volcanoes \| CIE IGCSE \... **[1,100 × 1,037]** **Lava flows:** since few lava flows reach much beyond 10km from the volcanic crispr, they do not cause much death and destruction as you might think. Lava flows may destroy farmland, buildings and lines of transport but lives are rarely lost **Ash:** can appear in the air during violent eruptions. Ash is carried in the wind and can affect a large area. The further away from the volcanos, the thinner the deposits of ash will be. Ash causes much damage by simply blanketing everything, from crops to roads. Roofs of buildings will collapse if the weight of the deposited ash is large. Ash thick air will stop humans and animals from breathing. **Pyroclastic flow:** lethal gasses released during eruptions. They are dense and keep close to the ground. VEI is the index for how explosive the volcano is There are 9 categories Christian Newhall and Steve Self created the VEI Level of eruption is also based on EC,PH,FE - - - - **Formation:** - Volcanoes can also form over **hotspots** - - - - **[Storm surges]** **Storm surge:** when wind pushes water on land **You need:** low pressure, high winds **How are they created/facts** - - - - **Formation** - - - **Impacts** - - - - - - - - **[Causes of volcanic and earthquake hazards]**  **The inner core** - - - - **The outer core** - - - - **The mantle** - - - - **The crust** - - - **2 types of crust:** **Oceanic crust:** crust, sea bed that sits below the crust. More dense, weighs more **Continental crust:** land crust tectonic plates move at the same pace our nails grow +---------+---------+---------+---------+---------+---------+---------+ | **Plate | **Type | **Direc | **Examp | **Earth | **Volca | **Fold | | margin | of | tion | le | quake** | no** | mountai | | + type | crust | of | of | | | ns** | | of | involve | plate | locatio | | | | | stress* | d** | margin* | n** | | | | | * | | * | | | | | +=========+=========+=========+=========+=========+=========+=========+ | constru | Oceanic | ← → | Mid-oce | Less | Less | no | | ctive/d | to | | anic | violent | violent | | | ivergen | oceanic | | ridge | | | | | t | /contin | | (eg mid | | | | | tension | ental | | atlanti | | | | | | | | c | | | | | | | | rift) | | | | +---------+---------+---------+---------+---------+---------+---------+ | destruc | Oceanic | | South | violent | violent | yes | | tive/co | to | | America | | | | | nvergen | contine | | | | | | | t | ntal | | | | | | | compres | | | | | | | | sion | | | | | | | +---------+---------+---------+---------+---------+---------+---------+ | collisi | Contine |  | malayas | | | | | compres | contine | | Eurasia | | | | | sion | ntal | | n | | | | | | | | + | | | | | | | | Indian | | | | | | | | plate | | | | +---------+---------+---------+---------+---------+---------+---------+ | conserv | Con-con | | North | violent | rare | no | | ative/t | | | America | | | | | ransfor | con-oce | | n | | | | | m/shear | anic | | plate | | | | | ing | | | | | | | +---------+---------+---------+---------+---------+---------+---------+ - - - - - - - - - **[Destructive (convergent)]** 1. 2. 3. E.G.: Nazca/South American tectonic plates + Peru/Chile trench + Andes Mountains  **[Constructive (divergent)]** 1. 2. 3. E.G.: North American/Eurasian tectonic plates + Mid Atlantic Ridge **[Transform (conservative)]** 1. 2. 3. 4. **[Collision]** 1. 2. 3. E.G.: Indian plate/Eurasian tectonic plates + Himalayas **[Why do people continue to live in areas at risk from hazard events?]** - - - - - - **Volcano:** - - - - - - - - - - **Earthquake** - - **[How are some countries more vulnerable than others to the impacts of natural hazards]** - - - - **[Categories of hazards]** **Geological:** - - - **Climatic:** - - - **Biological:** - - - **Technological** - - - **[Impacts:]** Shorter term: immediate effects E.g: ground shaking, fires, aftershocks, downed power lines Longer term: effects that happen later on - days/weeks/months afterwards E.g contamination of water supplies by ash falling on them, injuries (physical or mental health), crops destroyed by lava flow - **[Case studies (earthquake, typhoon, volcano)]** **Earthquake:** **Typhoon:****Volcano** **[Reducing the impact of earthquakes]** **Survival kit:** - - - - **Risk assessment** **Prediction** -------------------------------------------------------------------------------------------------- ----------------------------------------------------------------------------------------------- Distribution - where it\'s most likely to happen Toads evacuate their breeding colony days before the 2009 earthquake Frequency - how often/when is it likely to happen When a rock is stressed it begins to expand. This stress get caused by an upcoming earthquake Scale - how bad is it likely to be Snakes will move out of their nests before an earthquake, even in the cold Predictability - how much advance warning would we get? Will there be foreshocks/aftershocks etc Electromagnetic fields change **Ways to prepare for earthquakes:** - - - - **Emergency relief can reduce the impact of earthquakes by:** - - **Park model:** shows the effects of a hazard on quality of life over a sequence of time.  1 - risk assessment for furutre hazards 2 - hazard moving for future events 3 - rescuing people trapped in buildings/under rubble 4 - providing medical assistance 5 - ongoing distribution of water and clothing 6 - setting up temporary shelter 7 - clearing away rubble ready for rebuilding 8 - restoring basic services such as water, sewage, gas, electricity etc 9 - starting to rebuild school, hospitals, homes, etc 10 - looking back at the disaster and reviewing/appraising how well emergency operations worked **Short term responses in Nepal:** - - - - **Long term responses in Nepal:** - - -