Component 2 - Environmental and Development Issues Flashcards
What do we mean by glaicals?
Cold periods in the earth’s history when glaciers (Ice) have advanced (got bigger/larger)
What are interglacials?
Warmer periods in the earth’s history when glaciers have retreated (gone backwards) and ice sheets have decreased in size.
What period are we currently in?
Interglacial period
What has the interglacial period been dominated by?
Cold climates and ice shaping the land
The warmer and cooler periods experienced on earth according to Milankovic are caused by the combination of two things. What are they?
1) Shape of the earth’s orbit around the sun (Circular orbits result in glacials)
2) Tilt of the earth’s axis (The natural wobble of the Earth as it moves around the sun. This affects the tilt of the Earth and the amount of energy it receives by the sun. The greater the angle of the tilt the hotter the summers and the colder the winters are)
What is one other natural cause of climate change?
Volcanic eruptions
Give 2 examples of greenhouse gasses
Methane and carbon dioxide
What is short wave energy?
Light from the sun
What is long wave energy?
Heat from the sun
Carbon is one of the most common elements in the environment. Where do we find it?
- All organic substances i.e. all living things,
- Simple compounds such as CO₂ which exists as a gas in the atmosphere and is dissolved in the oceans.
- Complex compounds such for example hydrocarbons found is fossil fuels such as oil, coal and gas.
What is a carbon sink?
Places where carbon is stored over very long periods of time.
Carbon is transferred from one part of the environment to another in a cycle known as what?
The carbon cycle
What is the keeling curve?
Graph that shows the rise of CO₂ in the atmosphere
What evidence is there of climate change?
- Ice cores
- Tree rings
The global circulation is a worldwide system of winds which transports heat from the tropical to polar ______
Latitude
At the equator ______ heats the Earth which in turn heats up the air above.
Insolation
Hot air rises, creating ______ pressure.
Low pressure
When the air reaches the ______ it cannot go any further and travels north and south.
Tropopause
This air becomes colder and heavier, and at around 30 degrees north and south it falls creating ______ pressure.
High pressure
Air from the north and south then returns to the equator and meets an area known as ______.
ITCZ (Intertropical Convergence Zone)
A large circulation of air is thus created, known as the ______ cell.
Hadley
Air rises again at around 60 degrees north and south and descends again around 90 degrees north and south, creating a further two less distinct cells: The ___(1)___ cell and the ___(2)___ cell.
1) Ferrel
2) Polar
How is low pressure formed?
Air warms and rises, leading to low pressure at the surface
When do tropical storms occur in the Northern Hemisphere?
Between June and November - it peaks in September
When do tropical storms occur in the Southern Hemisphere?
Between November and April
What are hurricanes also called?
Typhoons and cyclones
What does the sea’s temperature have to be for a cyclone to form?
27°C
How are towering clouds and torrential rain formed?
The warm sea water heats the air above it, causing it to rise, creating an area of very low pressure in the atmosphere
As the air moves towards the centre of the low pressure it spirals upwards into the atmosphere. This is due to the Earth’s rotation - what is this called?
The Coriolis Effect
Cyclone Pam hit the island chain of _____(1)______ in ________(2)__________
1) Vanuatu in the South Pacific
2) 13th March 2015
What category was Cyclone Pam?
5
Give 6 impacts of Cyclone Pam
1) 11 people died
2) 90000 people were made homeless
3) 80% of subsistence crops were flattened
4) Coastal areas were flooded due to the storm surge
5) Freshwater wells were contaminated
6) Winds over 250 kmph destroyed schools and hospitals
Give 6 responses to Cyclone Pam
1) Emergency aid was sent by Australia, Fiji, France, New Zealand and the UK
2) Repairs provided safe drinking water
3) Blankets distributed to the homeless
4) 153 temporary schools were set up
5) Foreign medical teams sent
6) 19000 children vaccinated against measles
The monsoon rains occur each year across South Asia. They are formed as ______
The ITCZ moves northwards across India
How does South Africa have its monsoon season?
1) The ground is strongly heated by solar energy
2) The air rises, creating a zone of low pressure
3) The moist air from above the Indian Ocean is drawn into the area of low pressure
4) The moisture condenses, forming towering clouds
Give 4 impacts of the 2015 flash floods in South Asia caused by the monsoon season.
1) Impermeable tarmac and concrete fast runoff causing flash floods
2) Storm drains cannot cope so sewage and rainwater floods the streets
3) More than 120 people drowned in India
4) People lost their homes, people temporarily lost their homes
What is the definition for a ‘heatwave’?
An extended period of hot weather relative to the expected conditions at that time of year.
What is the definition for ‘drought’?
A lack of precipitation in an area for a long period of time, often several months or years.
What is high pressure?
When cool air sinks
What are droughts the result of?
- A lack of rainfall
- An environment that is poor at storing and retaining water
- Hot weather which increases evaporation of water
What caused the drought in California?
1) 3 Years of significantly less rainfall
2) Lower winter rainfall due to the position of the jet stream (strong ribbon of wind that circles the globe they seperate cold polar air masses to the north and the warmer tropical air masses to the south)
3) Dry air to the west of California that didn’t move or break up
4) Low air pressure and cold air from Canada was dragged down into the central and eastern areas of the USA missing California.
What were the social, environmental and economic impacts of the drought in California?
1) 17,000 agricultural (farming) jobs were lost
2) Crop failure therefore food prices rose by 6%, Salmon and Trout died as the water had less oxygen in it due to the heat and falling levels of water
3) Most Hydroelectric Power (HEP) dams stopped producing electricity
4) Groundwater supplies were not recharged
5) Wildfires increased by 36%