Natural hazards and climate change Flashcards
Why does it rain?
air rises because it’s hot, there is an obstacle in the way (mountain) or because cold air forces it upwards. It then cools in the atmosphere. This creates condensation and clouds. Eventually, the clouds are too dense and rain falls
What does low pressure systems bring?
Clouds and rainfall, as hot air rises and cools
What does high pressure systems bring?
Dry, dense air as cold air sinks. This either creates very hot days or very cold days, with no clouds and dry conditions.
Wind blows out of high pressure systems
Why is it hot and wet in the rainforests?
Around the equator, the sun is the most concentrated, so the solar heat makes the sea hotter. The oceans evaporate, creating a low pressure system and creating lots of rain.
What is the Coriolis effect?
The wind moves in spirals as the earth is constantly spinning
What are the pressure systems called across the globe?
Polar highs - 90*
Sub polar low - 60*
Sub tropical high - 30*
Equatorial low - 0*
What are the wind cells across the globe?
0* - 30* = Hadley cell
30* - 60* = Ferrel cell
60* - 90* = Polar cell
What way are the winds deflected in the north and south?
The anti-clockwise rotation in the northern hemisphere deflects winds to the right
The clockwise rotation in the Southern Hemisphere deflects the winds to the left.
What temperature does the ocean need to be at to create a storm?
27 degrees Celsius
When does water vapour condense?
1 degree Celsius per 100m
What’s the scale to measure tropical storms?
The saffir-Simpson scale
Where did tropical storm Haiyan hit?
The Philippines, coming into south east Asia
How many people did Haiyan kill?
6,340
Why was the storm in Haiyan so devastating?
The Philippines are LICs and they didn’t predict the storm surge, so people were caught off guard when they hid in basements.
What is the other names for High and low pressure systems?
High pressure - anticyclone
Low pressure - depression
How did the beast from the east form?
Snowstorm from Russia met storm Emma from Ireland over Britain
What were the weather stats of the beast of the east?
20 inch snow 160mph winds in Europe (top speed) -12 degrees Celsius (lowest temp) Blizzards Floods 40cm higher than expected in Cornwall
How are storms formed?
The sun heats up the ocean to over 27 degrees
This causes moist air to rise, creating low pressure at the centre of the storm
This air cools as it rises, at 1 degree per 100m, this causes condensation and clouds to form
Some cooled air sinks back down
Air rushes from high pressure areas outside of the storm to lower pressure areas at the centre of the storm, creating winds
It spins because of the earths rotation
When it reaches land, the source of power fades so it dies
When was Beast from the east?
22nd Feb 2018 - 4th March
Primary effects of beast from the east?
Blizzards
20 inch snow
Floods of 40cm higher in Cornwall
160mph wind in Europe
-12 degrees as the lowest temperature
14 deaths in U.K.
Short term responses of beast from the beast?
Red alert issued
Transport stopped
Firefighters come to help
People stocked up on food
4x4 drivers brought supplies around
When was Haiyan?
8th November 2013
How many homeless people in Haiyan?
Over 4,000,000 homes destroyed
How much money lost in Haiyan?
$20 billion cost
$5. 8 billion for rebuilding
Immediate responses in Haiyan?
1,600 evac centres set up
Makeshift rafts (out of mattresses) were made to get across the storm surge
In first 10 days England delivered 2,000 tonnes of aid
Primary effects in Haiyan?
95% of trees uprooted
Flood water 20ft deep
Boats were destroyed - leaving them stranded
Secondary effects in Haiyan?
Looting - aid was really slow
Stagnant water attracted mosquitos, spreading malaria
Phone coverage was lost
Shocked into birth- lots of pregnancies
Roads were blocked by debris
6 million lost their jobs
Long term responses in Haiyan?
Fish and trees were destroyed, leading to decrease in money
Oxfam says ‘3-5 years recovery’
What caused the earthquake in Japan?
It was a megathrust so the pacific and Eurasian plate collided in the ocean at a shallow focus and a plate was pushed up, sending a tsunami.
When did the earthquake in Japan happen?
11th March 2011
What was the Japan earthquake on the Richter scale?
A 9
How many people dead in the Japan earthquake?
15,853
What were the primary effects of the earthquake in Japan?
Some shuddering and 4 trains were derailed but protections mostly held and everybody was generally okay
What caused the most damage in Japan?
The tsunami