Textbook Notes (368,432)
Canada (161,877)
Geography (106)
GG231 (31)
Chapter 1

Chapter 1.docx

3 Pages
Unlock Document

Alireza Ghaffari

Risks and Disasters Reading #1 (Module 1) Chapter 1 pg 1-10 - Fundamental reality in study of natural hazards = people/gov’t poorly prepared for rare natural disasters - E.g., Haiti Earthquake o Jan 12, 2010 o Haiti = on Carribean lithospheric plate & at northern edge of carribean plate o @East – Carribean plate is subducting (moving beneath) the North America plate - Backdrop for a catastrophe o Lithosphere = slowly moving lithospheric plates o Earthquakes are common at and near plate boundaries  Spreading ridges – where new crust is created  Subduction zones – where one plate moves beneath another  Transform faults –where two plates move laterally and passing one another - Buildings of all types failed - Slopes of Haiti have slums, which lack proper foundations, so they slid down hillsides - Seaport ceased to function due to damage caused by liquefaction of loose, water-saturated sediment - Earthquakes the same size happen in different places – this one was so historic because: o Occurred in heavily populated area o Buildings in the area were not constructed to withstand strong seismic shakin  Access to resources is limited – people focus on this not disaster protocols etc. 1.1 Why Studying Natural Hazards Is Important - Financial loss, loss of life - No area is hazard free Hazardous Natural Processes and Energy Sources - Process = how events affect the earth’s surface  processes are driven by energy - 3 energy sources: o Earths internal heat  produces slow convection in the mantle  Earthquakes and volcanic eruptions  Most occur at boundaries between tectonic plates o The sun  warms Earth’s atmosphere and surface, producing winds and evaporating water  Circulation of winds/water = climate  Violent storms, floods, drought, coastal erosion o Gravitational attraction of Earth  attraction of surgace materials to center of the earth  Causes rock, soil, snow, to move downslope  Attracts stuff that strikes earths surface - Energy used by hazard varies (more area it affects generally means more energy used) - Not all hazards are natural – e.g., H1N1 in humans, warfare - Distinction becoming blurred Hazard, Risk, Disaster, and Catastrophe - Hazard: any natural process that threatens human life or property - Risk: the probability that a particular destructive event will occur multiplied by the event’s likely impact on people and property o Integrates hazard and social and economic vulnerability - Disaster & Catastrophe: events that cause serious injury, loss of life, and property damage over a limited time and within a specific geographic area. o Distinction is vague o Catastrope = more massive and affects more people/infrastructure o Disasters = regional/national vs. catastrophe = consequences felt far beyond that area itself - UN @ 1990’s = International Decade for Natural Hazards Reduction o To minimize loss of life and damage  loss actually iNCREASED o To achieve goals  mitigation necessary (mitigation = efforts to prepare)  E.g., to mitigate effects of contamination = deploy water treatment plants, disinfect, bottled water Death and Damage Caused by Natural Hazards - Tornadoes and windstorms cause the largest # of deaths each year in North America - Earthquakes don’t cause much loss of life but causes LOTS of property damage - Above relationship b/w loss and life and property damage apply only to fully developed world NA, EU, AU, JA, NZ - Disasters in developing countries claim much more lives - In NA disasters have huge toll on economy o E.g., Category 4 & 5 hurricanes cost billions - Natural hazards differ in potential to cause catastrophe b/c of difference in size of affected area o Climate change, super volcanoes, large meteorites = global repercussions o Large tsunami, earthquakes, volcanoes, hurricanes, monsoons, floods @ large rivers = regional effects o Landslides, avalanches, floods @ small streams, wildfires, tornadoes affect small areas - Natural hazard risks change over time b/c of changes in population and land use 1.2 Magnitude and Frequency of Hazardous Events - Impact: partly function of its magnitude/energy released, partly function of frequency - Magnitude-frequency concept: inverse exponential relationship exists b/w magnitude of an event and frequency o M = F  e-x o Magnitude, frequency, e, x = constant - MFC also = Earth’s surface is shaped mainly by events of moderate magnitude and frequency (vs. low/high) - Impact also influenced by climate, geology, vegetation, population and land use o E.g., Land Use – levees to reduce floods – larger more frequent floods  Hurricane Mitch & flood @ Yangtze river in China = b/c of deforestation (via forest fires & timber respectively)  2004 Tsunami – b/c of increased populations along shores of Indian ocean  Hurricane Katrina – removed Wetlands that could have buffered storm surge Chapter 1 pg 19-29 1.5 Fundamental Concepts for Understanding Natural Processes as Hazards 1. Hazards can be understood through scientific investigation and analysis Science and Natural Hazards - Scientific method = series of steps - Step 1 = formulate question  hypothesis = possible answer to the question, idea that is tested - Scientists info about frequency, magnitude, type + knowledge of frequency of past events = map future events - Search for precursors – e.g., foreshocks of earthquake Hazardous Processes Are Natural - Because the processes are natural, we face philosophical issues when trying to figu
More Less

Related notes for GG231

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.