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
