Atmosphere and weather
Climate change
Evidence for climate Tree rings
change Warm, wet years = wider rings and more growth and light rings
show spring/summer growth
Have proven to show Ice age
Ice cores
They contain record of past atmospheric conditions - and traps
tiny bubbles containing GHGs and scientists can measure the
composition
Sea levels rising 19cm since 1900
Ocean temps warmest they have been since 1850
Increase in wildfires and number of storms and flooding
Human causes Burning fossil fuels
Release of CO2 and Methane - CO2 280ppm in 1750 to over
420ppm today
Global fossil fuel combustion accounts for 75% of total GHG
emissions and 90% of all CO2 emissions
Agriculture
Accounts for around 15% of total GHG emission e.g cow farming
- can produce 70kg of methane per year
Rice farming and nitrous oxide from fertilisers
Deforestation
Trees used as carbon sinks and when cut down and burnt CO2 is
released
Tropical forest stores 250 tonnes of carbon per ha
Approx 500m trees cut down in Amazon in 2021 alone
Natural causes Volcanic explosions
Short term = sulphur dioxide and ash into stratosphere
creates a blanket where it reflects sunlight back into
space, reducing global temps
E.g Mt Pinatubo 1991 Philippines, 20m tonnes of sulphur
dioxide = global temps to drop 0.5 degrees Celsius globally
Long term CO2 is emitted into atmosphere (GHG) =
traps heat and generates a long-term warning
Eccentricity = 100,000-year cycle, changes seasonal
contrast due to different orbits around the sun
Axil tilt - 41,000-year cycle -changing degree of tilt.
Currently 23.4. Less of an angle = weaker seasons
Solar flares = intense bursts of radiation of the sun,
caused by release of magnetic energy. 11-year cycle
with high and low activity
Impact locally Uk - record 40.3 degrees in July 2022 - 3,000+ heat related deaths
UK - sea level rising 3-4mm per year = river Thames barrier has been
closed 200+ times to prevent flooding
Climate change
Evidence for climate Tree rings
change Warm, wet years = wider rings and more growth and light rings
show spring/summer growth
Have proven to show Ice age
Ice cores
They contain record of past atmospheric conditions - and traps
tiny bubbles containing GHGs and scientists can measure the
composition
Sea levels rising 19cm since 1900
Ocean temps warmest they have been since 1850
Increase in wildfires and number of storms and flooding
Human causes Burning fossil fuels
Release of CO2 and Methane - CO2 280ppm in 1750 to over
420ppm today
Global fossil fuel combustion accounts for 75% of total GHG
emissions and 90% of all CO2 emissions
Agriculture
Accounts for around 15% of total GHG emission e.g cow farming
- can produce 70kg of methane per year
Rice farming and nitrous oxide from fertilisers
Deforestation
Trees used as carbon sinks and when cut down and burnt CO2 is
released
Tropical forest stores 250 tonnes of carbon per ha
Approx 500m trees cut down in Amazon in 2021 alone
Natural causes Volcanic explosions
Short term = sulphur dioxide and ash into stratosphere
creates a blanket where it reflects sunlight back into
space, reducing global temps
E.g Mt Pinatubo 1991 Philippines, 20m tonnes of sulphur
dioxide = global temps to drop 0.5 degrees Celsius globally
Long term CO2 is emitted into atmosphere (GHG) =
traps heat and generates a long-term warning
Eccentricity = 100,000-year cycle, changes seasonal
contrast due to different orbits around the sun
Axil tilt - 41,000-year cycle -changing degree of tilt.
Currently 23.4. Less of an angle = weaker seasons
Solar flares = intense bursts of radiation of the sun,
caused by release of magnetic energy. 11-year cycle
with high and low activity
Impact locally Uk - record 40.3 degrees in July 2022 - 3,000+ heat related deaths
UK - sea level rising 3-4mm per year = river Thames barrier has been
closed 200+ times to prevent flooding
