World at risk - EQ2

?
Magnitude
Strength of hazard
1 of 17
Frequency
How often the hazard occurs
2 of 17
What is El Nino and La Nina?
Changes in the circulation of warm and cold water in the Pacific ocean
3 of 17
Normal year
Australia - warm, moist air rises, cools and condenses forming rain clouds, South America - high air pressure, descending air, upwelling cool water
4 of 17
El Nino year
Australia - high air pressure, descending air = droughts and wildfires, South America - low air pressure = floods, warm water moves east to South America from Australia, where the warm air rises forming rain clouds
5 of 17
La Nina Year
Australia - low air pressure, storm clouds = floods, South America - high air pressure = droughts, warm water pushed east and warm air rises forming storm clouds
6 of 17
How have natural hazards changed over time?
Hydro-metrological hazards have increase because of global warming, number of deaths have decreased because of better education, respons, bulindings - before 1930 there were a large number of deaths
7 of 17
How have natural hazards changed over time?
Increase in economic damage as increase in world population therefore more homes being built then destroyed, number of people affected increases as larger population
8 of 17
El Nino - Peru
1997 -98, in Northern Peru well built modern structures were washed away, Peru lost 30 major bridges, 250 people drowned
9 of 17
El Nino
In total 350,00 homes were lost, storms spread down to Chile, in Chile over 80,00 people lost their homes, Brazil rivers dried up and rivers spread, River hooded in Argentina rose by 27ft, Mississippi had 1 ft of snow
10 of 17
El Nino
Smoke from fires caused air signal problems for planes in Florida, scientists think global warming is the cause of El Nino, in late 1998 - La Nina, Hurricane Mitch - 1 million lost their homes, set countries economy back by over 30 years
11 of 17
Flooding in Bangladesh - Background information
One of the world's most densely populated countries, population of 125 million inhabitants, one of the world's most poorest countries, GNP of $200 per head
12 of 17
Flooding in Bangladesh - Background information
Three of the world's most powerful rivers passing through it - The Ganges, The Meghna and The Brahmaputra, contains virtually no raw materials or rock, floods and storms every year and living in vulnerable areas as it's cheaper,
13 of 17
Flooding in Bangladesh - Background information
Frequency increased rapidly since 1975 because of global warming, the frequency is exponentially
14 of 17
Why is flooding in the Bangladesh becoming seen as an increasing threat?
snow melts and goes into 4 rivers, 40% of Dhaka underwater, deforestation, soil erosion which then builds up in the rivers, 10 year cycle, however this year it was 3 years early, they think this is due to global warming
15 of 17
Why is flooding in the Bangladesh becoming seen as an increasing threat?
Irrigation stops the river from flowing into the sea, all 3 rivers impact = lot worse impact, sea level rises 7mm, land only rises 5/6mm a year this is because of global warming, 60% of land covered by buildings, deforestation leads to an increase i
16 of 17
Why is flooding in the Bangladesh becoming seen as an increasing threat?
Deforestation leads to an increase in landslides, dams in India increase sedimentation which blocks up the river, 70% of land is 1mm below sea level, annual rainfall is 2000mm - Hertfordshire is 900mm
17 of 17

Other cards in this set

Card 2

Front

Frequency

Back

How often the hazard occurs

Card 3

Front

What is El Nino and La Nina?

Back

Preview of the front of card 3

Card 4

Front

Normal year

Back

Preview of the front of card 4

Card 5

Front

El Nino year

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Geography resources:

See all Geography resources »See all Natural hazards resources »