Hazards Flashcards
What is the disaster/risk equation?
Define frequency?
How often an event of a certain size (magnitude) occurs.
Define magnitude?
The size or strength of an event eg. the size of an event on the Richter scale
What are the factors that have caused the numbers of reported natural disasters to increase in the 20th Century?
New technologies
International monitoring
24/7 Media
Why have the numbers of deaths from natural disasters decreased in recent years?
Increased understanding of disasters
Better technology
Better preparedness
Name an international disaster database?
EM-DAT
Sigma
CRED
Name the major greenhouse gases?
Carbon Dioxide
Methane
Water Vapour
CFCs
Sulphur Dioxide
Nitrous Oxides
How often do El Nino events occur?
Every 3- 7 years
What is the name of normal Pacific air circulation?
The Walker Circulation
What is the name given to the weather events triggered around the world by El Nino cycles
Teleconnections
Which weather hazard occurs during El Nino events in Northern Africa?
Drought
Which weather hazard occurs in California during El Nino events?
Flooding
What does ENSO stand for?
El Nino Southern Oscillation
La nina brings which weather hazard to South East Australia?
Flooding
El Nino brings which weather hazard to Peru and Chile?
Flash Floods
Name a particularly bad year for El Nino?
1997 - 8
Is there any evidence that the frequency or magnitude of geo-physical events is increasing over time?
No
What is thought to be the reason for a rising trend in hydro-meteorological events?
Cimate Change
Which human factors could account for the rising trend of hydro-meteorological hazards?
Improved technology
24 hour media
When did Hurricane Katrina occur?
August 2005
Name the pre-requisites for hurricane formation?
Ocean temperatures over 28 degrees C
Within 5 - 30 degrees latitude
Lack of upper atmosphere jet stream
Water over 100m deep
The location of earthquakes is closely related to what?
Plate margins
Name the drought areas?
SE Australia
Sahelian Africa
Great Plains USA
NE Brazil
Interior of Asia
Name the areas at risk of flood?
Brahmaputa/Ganges
Mekong
Mississippi
Danube/Rhine
East Africa
Mozambique
SE Brazil
Central America
Define the term hazard hotspot?
A place which is affected by two or more natural hazards
Where are hurricanes found?
The North Atlantic/Caribbean
Where do the most dangerous volcanoes occur?
Destructive plate margins
What are tropical storms known as in Australia?
The Willy-Willies
Define Sub-Saharan Africa
The area of the continent of Africa that lies south of the Sahara Desert
Define risk?
The probability of a hazard event occurring and causing loss of lives and livelihoods
Define disaster?
A hazard becoming reality in an event that causes deaths and damage to goods/property and the environment
Define context hazard?
Widespread (global) threat due to environmental factors such as climate change
Define geophysical hazard?
A hazard formed by tectonic/geological processes
Define hazard?
A perceived natural event which has the potential to threaten both life and property
Define hydro-meteorological hazard?
A hazard formed by hydrological (floods) and atmospheric (storms and droughts) processes
Define vulnerability?
A high risk combined with an inability of individuals and communities to cope
Define albedo?
How much solar radiation a surface reflects
Define climate change?
Any long-term trend or shift in climate (average weather over 30 years)
Define enhanced greenhouse effect?
The levels of greenhouse gases in the atmosphere increasing due to human activity
Define fossil fuels?
Energy sources that are rich in carbon and which release carbon dioxide when burnt eg. coal
Define global warming?
A recently measured rise in the average surface temperature of the planet
Define greenhouse effect?
The warming of the Earth’s atmosphere due to the trapping of heat that would otherwise be radiated back to space - it enables the survival of life on Earth
Define tipping point?
The point at which a system switches from one state to another
Define feedback mechanism?
Where the outpur of a system acts to amplify (positive) or reduce (negative) further output
Which scale is used to measure hurricanes?
Saffir-Simpson (1 - 5)
Which scale is used to measure earthquakes?
Richter scale (1 - 10 log scale)
Which scale is used to measure tornadoes?
Fujita intensity index
Which scale is used to measure volcanoes?
Volcanic explosivity index
What is the relationship between magnitude and frequency in hazard events?
High magnitude events occur less frequently and vice-versa
What system is used to name hurricanes?
Male then female first names
Define asthenosphere?
A semi-molten zone of rock underlying the Earth’s surface
What type of plate boundary is this?
Collision
What type of plate boundary is this?
Conservative
What type of plate boundary is this?
Constructive
What type of plate boundary is this?
Destructive
Define lithosphere?
The crust of the Earth, around 80-90km thick
Define magma?
Molten material that rises towards the Earth’s surface when hotspots within the asthenosphere generate convection currents
What is a tectonic plate?
Rigid, less dense slab of rock floating on the asthenosphere
Define tectonic hotspot?
A localised area of the Earth’s crust with an unusually high temperature
Name a tectonic hotspot?
The Hawaiian islands
Define plume?
An upwelling of abnormally hot rock within the Earth’s mantle
What is the ITCZ?
Inter-tropical convergence zone
Name an MEDC disaster hotspot?
California, USA
Name an LEDC disaster hotspot?
The Philippines
What type of plate boundary does the Philippines sit on?
Destructive
Name the tectonic plates which meet on the Philippine boundary?
Philippine plate
Eurasion plate
Which hazards effect the Philippines?
Volcanoes
Flooding (monsoon)
Tsunami
Typhoons
Drought
Landslides
Name a volcanic eruption in the Philippines?
Pinatubo (1991)
700 killed
Name an earthquake in the Philippines?
Manila (1990)
6000 killed
When was the worst Philippine tsunami?
1976
How many people live in California?
40 million
Which hazards effect California?
Earthquakes
Fog
Drought
Wildfires
El Nino
Flooding
Landslides
Which tectonic fault runs through California?
San Andreas
Name an earthquake in California?
Loma Prieta (1989)
What type of tectonic boundary does California sit on?
Conservative
Define climate?
The average conditions of precipitation, temperature, pressure and wind measured over a 30 year period
What was the Little Ice Age?
A cool period in Europe where Alpine glaciers advanced
When was the Little Ice Age?
1400 - 1850 AD
What was the Medieval Warm Period?
A period of unusually warm North Atlantic climate
When was the Medieval Warm Period?
800 - 1400AD
Name the 2 sources of evidence for long-term climate change?
Ice cores
Pollen analysis
Which molecules are studied from the Antarctic ice cores?
Carbon dioxide
Oxygen isotopes
What is the natural level of atmospheric carbon dioxide in the last 800,000 years?
180 - 280ppm
What is the current level of atmospheric carbon dioxide?
400ppm
Name the 3 sources of evidence for medium-term climate change?
Historical records
Tree rings
Retreating glaciers
Define thermal expansion?
The increased volume of the oceans as a result of their higher water temperature leading to sea-level rise
What is climate forcing?
Ant mechanism that alters the global energy balance and “forces” the climate to change in response
What is the recent source of evidence for climate change?
The instrumental record
Name the 3 natural drivers of climate change?
Astronomical forcing (Milankovitch cycles)
Solar output
Volcanic and cosmic causes
What are the 3 Milankovitch cycles?
Change in orbit (100,000 year cycle)
Change in axial tilt (41,000 year cycle)
Axial wobble (22,000 year cycle)
What does IPCC stand for?
Inter-governmental Panel on Climate Change
Why is it difficult to predict future climate change?
Greenhouse gas levels uncertain
Feedback mechanisms umpredictable
Global dimming influence unresearched
Role of natural process uncertain
Why do we think climate change is due to human activity?
CO2 level way above historical natural levels
Increasing extreme weather events
Recent decade hottest on record
Temperature rises recorded on all continents
Satellites record rising sea-levels
What is this?
Thermohaline Circulation
Where does the data for this CO2 proxy temperature record come from?
Vostok, Antarctica
Whay are historical records like the painting below unrelaible?
Did not set out to record climate
Local record
Artists interpretation
Difficult to generalise
Define ecological impacts?
Activities which effect the interactions between plants and animals (food chains,webs etc)
Define environmental impacts?
Activities which pollute or damage terrestrial systems, the oceans or the atmosphere (eg. industrial waste greenhouse gases)
Define permafrost?
Permanently frozen ground
Define habitat?
The environment of plants and animals, in which they live, feed and produce
Name 4 environmental impacts of climate change on the Arctic?
Major vegetation zones will shift North
Unfreezing of the permafrost
Increased coastal erosion
Loss of ice cover
Release of methane gas from thawing lakes
Name 4 ecological impacts of climate change in the Arctic?
Existing food webs destabilised
Lakes drain as ground thaws removing fish habitats eg Arctic Char
Alien insect species invade causing tree death
More UV destroys marine phytoplankton at base of food chain
Which marine species are dependent on Arctic sea ice?
Polar bears
walruses
Seals
Which land species are dependent on Arctic sea ice?
Lemming
Vole
Arctic Fox
Snowy Owl
Caribou
Name 4 social impacts of climate change on the Arctic?
Loss of indigenous hunting culture
Decline in freshwater fisheries eg Arctic char
Increase in marine fish species eg. cod
Enhanced agriculture and forestry
More exploitation of oil, gas. timber and fish
Name 4 social impacts of climate change on Africa?
Increase in vector-borne disease
Food insecurity
Lack of fresh water
Lack of money to combat climate change
Name 4 environmental impacts of climate change on Africa?
Desertified grasslands
Loss of biodiversity
Coastal erosion due to sea level rises
Coral bleaching
Name 4 economic impacts of climate change on Africa?
Reduction in hydro-electric power generation
Reduced food production
Water conflicts increase poverty levels
Environmental refugees increase pressure on services
Define eustatic change?
Change in sea level due to change in the amount of water in the oceans
Define isostatic change?
Movement of land in response to loss or gain of mass (eg. melting ice sheets leads to uplift)
A 15 metre rise in sea levels by the end of the century relies on which 4 changes occuring?
West Antarctic ice sheet melts - 5m rise
Greenland ice sheet melts - 7m rise
World’s glacier systems melt - 2m rise
Thermal expansion of oceans - 1m rise
Why is it difficult to predict future sea level rises?
Unpredictable greenhouse gas emissions
Business as usual or more sustainable approach adopted
Thermal expansion/glacial melt unpredictable
Name the 3 types of area vulnerable to sea level rise?
Large river deltas
Areas that lie close to sea level
Small low lying islands
Name a large river delta
Brahmaputra-Ganges
Nile
Mississippi
Name an area close to sea level?
The Netherlands
Parts of Eastern England
Name 3 low lying islands?
Kiribati
Tuvalu
Maldives
Marshall Islands
Vanuatu
Carteret Island
What does IPCC stand for?
Inter-governmental Panel on Climate Change
Define tipping point?
When climate change occurs irreversibly and at an increasing rate
Why is it difficult to predict future emission levels?
The future rate of growth in developing countries
Future international action
Inertia in the system
Impact of positive feedback mechanisms
The Stern Report predicts catastrophic changes above which average temperature increase?
5C
Name this location?
The Nile Delta
Name 4 countries in the Arctic Circle?
Sweden
Norway
Finland
Canada
USA
Russia
Greenland
Name this ecosystem?
Mangrove
Which process is this?
Carbon capture and storage
Define biofuel?
Fuel such as ethanol extracted from plants
Why is progress on mitigation of climate change not faster?
Uncertainty
Costs
Political inertia
Economic systems
International agreements
What is the level of consensus on climate change?
High
It iss both scientific and political
What are “climate crusaders”?
Individuals or groups who keep climate change in the news:
Usually famous
