Climate shifted between cold
glacial periods last 100,000
years and warmer interglacial
periods that last 10,000 years
Ice Cores- drill into ice sheets to get
ice cores layer of ice forms every year.
Analyse the gases trapped to tell what
the temperature was each year and
how its changed over time
Pollen Analysis- Pollen preserved in
sediment can be identified and dated to
show when it was released. Can tell what
the conditions were like from the plant
Sea level change- Affected by the volume of
water stored as ice sea levels are shown by
raised beaches can be dated to when there was
less water
Medium Term
Last glacial period ended
18,000 years ago.
Warming of the climate was fast
but it wasn't constant switched
back to cooler climate
5000 years ago temperatures
were 1-2C higher
Historical Records- Indicate
different conditions in the
past
Tree Rings- New ring each year and if
conditions are good they will be thicker.
Can look at how many rings and the
thickness to see the climate of that year.
Retreating Glaciers- See how big
glacier was and how far it extended by
rocks deposited the distance shows
climate change further away its
increased
Short Term
Global warming used for
rapidly increasing global
temperatures risen sharply
recently.
Overall pattern increase in
temperature
Rose steadily from early 20th
century until 1940s then dropped
back down but have risen again
rapidly
Weather Records-
weather conditions have
been collected since 1861
can see climate change
over a short time
Polar Ice Melt- reduction in the
amount of ice at both poles
increased melting means increased
temperatures
Ecosystem changes- Affect
availability of food and shelter and
where species live can see
distribution of species has changed