cenozoic climate change 2

Question 1

what happened in the eemian?

Answer 1

127-118 thousand yrs ago

penultimate warm period

slighlt=y warmer than present

sea level 4-9m higher

wasnt just one warn event - short lived colder events

Question 2

what is terminal moraine

Answer 2

debris accumulated and pushed to front edge of glacier - deposited and unsorted rock

shows visible footprint of glaciers

Question 3

describe what is was like during glacial perids

Answer 3

cold dry
-120m lower sea level as water in ice
land bridges between continents

boreal
taiga
tundra

Question 4

describe what is was like inter during glacial perids

Answer 4

warm
humid

savanna
deserts
rainforests

Question 5

the last glacial maximum

Answer 5

23-19,000 yrs ago

coldest period of last 100,000 yrs

temps 7 degrees lower than beginning og glaciation

23 degrees cooler than present greenland
5 degrees cooler than present tropics

sea surface temps 4-5 degrees lower

seal level 120m below present

Question 6

what does bluemarble 3000 show

Answer 6

shows earth at last glacial maximum 21,000 yrs ago and end 1000 yrs into future

based of co2 emissions 2100

Question 7

which hemisphere ice sheet cover was impacted the mostno

Answer 7

northern hemisphere

Question 8

what was the very cold period called in the LGM

Answer 8

Younger Dryas - loch lomand

Question 9

the younger dryas

Answer 9

12,900 - 11,500 yrs ago

very cold short spell

hypothesis - outburst of flood path from lake agassiz in arctic. freshwater into oceans, impacted thermohaline current as its driven by desnity and stopped over turning circulaton which interuppted warm gulfstream

Question 10

what factors caused the spread of trees in early holocene

Answer 10

climate change

distance of glacial refuge ice

role of biotic factors - comp/soil/dispersal rates

Question 11

describe sequnece of trees in early holocene

Answer 11

pre boreal
boreal - warmer
atlantic - warmest period
sub-boreal - cooler
subatlantic

Question 12

what makes up the mid holocene climatic optimum

Answer 12

boreal and subboreal

Question 13

in the subatlantic phase what made there be an increase in veg and grases

Answer 13

humans
pasture
agricutlture

wood used for building

charcoal use-

Question 14

when did humans start impacting the world

Answer 14

20-40,000 yrs ago

Question 15

average weight of humans on earth

Answer 15

470 mill tonnes

Question 16

average weight of skeletons

Answer 16

75 million tonnes

Question 17

anthropocene

Answer 17

new epoch and geological time period makring commence of significant human imapct on ecosystems

Question 18

evidence of anthropocene

Answer 18

altered isotope due to atomic bomb

plastic bottles