5.3 Is the climate changing?

Question 1

what is anecdotal evidence and why is it unreliable?

Answer 1

relying on someone’s memory, there is no scientific evidence or data

Question 2

reliable evidence to support the theory of global warming has come from…?

Answer 2

temperature records, pollen in peat bogs, dendrochronology and ice cores

Question 3

what is peat?

Answer 3

an accumulation of partially decayed organic matter

Question 4

why doesn’t organic matter decay in peat?

Answer 4

the peat is water logged and therefore does not contain any oxygen and the conditions are acidic

Question 5

why is pollen good to use?

Answer 5

plants produce a lot, pollen grains and a tough outer layer and each plant species has conditions it prefers

Question 6

what is dendrochronology?

Answer 6

the study of the rings of tree trunks

Question 7

what is each ring?

Answer 7

a new layer of xylem vessels underneath the bark

Question 8

what does a thin ring mean?

Answer 8

cold and dry conditions that year

Question 9

how can ice cores be used to provide evidence for past climates?

Answer 9

the different oxygen isotopes and carbon dioxide gets trapped in bubbles within the ice