Environmental threats to our planet Flashcards
What is the Quaternary period
The most recent geological period covering the last 2.6 million years - several cold and warm periods
How has climate changed during the Quaternary period
Temperatures fluctuated widely but has gradually cooled
There has been inter-glacial episodes in between cold spikes (glacial episodes)
How has climate change been over the last 400,000 years
Inter-glacial episodes last for 10,000 years - ice retreats during warmer periods
Cold spikes last for 100,000 years - thick ice expands covering vast areas of continents
Temperatures have remained relatively stable and warmer for longer
What is evidence for climate change
Tree rings:
Narrow rings - cooler and drier past climate conditions
Wide rings - warmer and wetter past climate conditions
Ice cores:
Oxygen, carbon dioxide and methane can estimate past temperature by comparing it to present levels
Very reliable
Paintings and diaries:
Price increases for grain in Europe
Frost Fairs held on the frozen River Thames
What are natural causes for climate change
Changes in Earth’s orbit:
Axial tilt - when the angle of the tilt is greater
Eccentricity - circular orbit gives a colder periods while
Volcanic activity:
Sulphur dioxide and water vapour makes volcanic aerosol which reflects sunlight away which reduces global temperatures
Ash, liquids and gases are thrown into the atmosphere
How does human activities contribute to greenhouse gases
Carbon dioxide:
Burning fossil fuels
Deforestation
Methane:
Emitted from livestock
Decay of organic waste from landfill
Nitrous oxide:
Vehicle exhaust
Agriculture
What are the social impacts of sea level rise
600 million live in coastal areas less than 10 m above sea level
Job losses in fishing and tourism so they need to learn new skills
Migration and over crowding due to flooding
What are the economic impacts of sea level rise
Agricultural land is lost due to the sea or polluted by seawater
Transport infrastructure is damaged by flood water
Loss of income from tourism as beaches become flooded
What are the environmental impacts of sea level rise
Biodiversity is lost by bleaching in coral reefs
Mangrove forests (natural barriers to storms) are damaged
Freshwater sources are polluted by salty seawater
What are the social impacts of extreme weather events
Increased drought affects farming
Increased risk of disease, e.g. skin cancer
Winter related deaths decrease with milder winters
What are the economic impacts of extreme weather events
Increases investment in prediction and protection
Increases repair and insurance cost
Skiing industry may decline in the Alps as there will be less snow
What are the environmental impacts of extreme weather events
Forests experience more diseases and forest fires
Lower rainfall causes food shortages for orangutans in Indonesia
Flooding in South Asia increases rice yields
What are the social impacts of climate change on weather patterns in the UK
Elderly will be more vulnerable during heatwaves but suffer fewer cold related deaths in winter
Heating costs will reduce
Water shortages expected by the 2050s
What are the economic impacts of climate change on weather patterns in the UK
Growth in the tourist industry in the Lake District - creates jobs and increased revenue
Ski resorts forced to close due to lack of snow reduces revenue
What are the environmental impacts of climate change on weather patterns in the UK
Vegetation and ecosystems will move north - peaches and oranges may be grown in southern England
Agricultural productivity may increase under warmer conditions but require increased irrigation
What are the environmental impacts of climate change on seasonal patterns
Bird migration patterns will shift
Trees and plants will flower earlier
Wildlife could struggle if seasons don’t match up with their food supply
What are the social impacts of climate change on sea level around the UK
Cliff collapse puts properties at risk
What are the economic impacts of climate change on sea level around the UK
Salt marshes become flooded and eroded - managed retreat can create new salt marsh habitats
What are the environmental impacts of climate change on sea level around the UK
Thames Barrier needs expensive upgrading / to be replaced due to an increase of flooding on the Thames Estuary
Agricultural land may be lost due to retreat
Tourism industry could be affected by eroded beaches
What are the types of cells and what happens there
Polar:
Air sinks over the higher latitudes at the poles where it meets the ferrel cell and rises
Ferrel:
Joins sinking air at the hadley cell
Travels across mid latitude regions until the air rises along the border of the polar cell
Hadley:
Winds meet near the equator and warm air rises causing thunderstorms
Drier air flows out before sinking into subtropical areas
What does high and low pressure do
High (hadley and ferrel):
Cold air sinks
Clear, calm weather
Low (hadley and hadley):
Hot air rises
Stormy, cloudy weather
What is the characteristic of polar climate zones
Cold air from polar cell sinks
Spin of the Earth creates dry, icy winds
What is the characteristic of temperate climate zones
Warm ferrel and cold polar winds meet creating low pressure
Brings frequent rainfall
What is the characteristic of subtropical climate zones
Hadley and ferrel cell sinks creating high pressure
Creates a belt of deserts, 40°
What is the characteristic of tropical climate zones
Belt of low pressure where both hadley cells meet
Regular, heavy rainfall and thunderstorms in Malaysia
What are the extreme weather conditions around the world
Temperature:
Antarctica - coldest
Libya - hottest
Driest:
Death Valley, USA
Egypt
Wettest:
India
Windiest:
Antarctica
New Zealand
What is El Nino
Trade winds blow eastward
Water in Australia moves back towards eastern Pacific - sea level rises in Peru (prevents cold water rising and reduces fish stocks)
Water temperature increases in Peru - low pressure, more rainfall, increase risk of flooding
High pressure in Australia - brings drought, dry conditions
What is La Nina
Happens after El Nino
Australia will experience flooding
Sea temperatures are cold in Peru
