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