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Flashcards in Climate proxies and vegetation zones Deck (19)
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1

define proxy records

any line of evidence that provides an indirect measure of former climate and environments

2

what is the principal of uniformitarianism

'present is key to the past'

we have to assume geological processes observed at present have been occurring in same ways in the past

further we go back in time its harder to apply principal

3

give example of 2 places that link to idea of uniformitarianism

Antarctica 25 million yrs ago is newzealand in present day - same climate /rain

similar leaf litter - proxy

4

name 3 sources of proxy data

glaciology - ice cores - the proxy is what we measure in the ice core eg gases/ air bubbles

biological - tree rings - preserved layers

geological - oxygen isotopes or terrestrial - scatrches on rock indictae glacier

5

where can we get proxys from?

ice core

sediment core

ocean drilling

6

what does pollen do

carries male sex cells of flowering plannts (angiosperms) and cone producing plants (gymnosperms)

pollen distributed by wind or animals

pollen goes to female flower and fertilised egg whcih becomes a seed and produces plant

7

why does pollen work for proxy record

distinct morphology - shape/size etc
"pollen and spores; natures finger prints of plants"

each location produces unique pollen so specific it can be used to identify a characterics of place

8

what is the phsyiognomic approach

based on plant archetetcture constarined by env conditons eg temp/rainfall eg cacti

9

define biome

worlds communities classified according to vegetation and adaptations of orgaism to the env

10

idea of modern vs natural veg

modern is us today and human infulnces over land directly and indirectly so higher co2 conc and higher temps

natural - in past we didnt have higher co2 or warmer temps, less eroded soil less technology so would be very different

11

taiga/boreal forest

D climate
average >10 degrees
conifers larch pine

12

tropical rainfofrest

25 degrees constant
2000mm rain yr

high biodivesity

competition for light

brazil

13

tropical savanna

semi arid- semi humid

150-1150mm rain

AW climate

grassland with trees shurbs
comp for water
more water - mor trees
less water - more shrubs

africa/india

14

tropical climate zone

tropics of cancer at 23.5 degrees
brazil

all months above 18 degrres

can be rainforst/ decidous / savanna

15

west african veg

all different eg sahel, sudainian, rainforest

this is due to intertropical covergence zone which controls rain

16

what is the intertropical convergence zone

low presuusre

circumpolar equitorial band of clouds

convergence of winds

moves in seasonal cycling following zenith point

17

temperate decidious forest

moderlate climate

growing seaosn 140-200 days during frost free months

C climate

maple chestnut

uk

18

xerophytic desert shurbland

arid - evaporation over precipitation

150 mm rain

B climate

perennial veg thats survived 2 years semi desert

sahel

19

Tundra

permafrost

growign season 50-60 days

winter -34
summer 3-10 degrees

E climate
low shurbs mosses grasses

tree growth hindered by low temps