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Physical geography - Coggle Diagram
Physical geography
The Arctic Tundra
Facts
Water cycle
Carbon cycle
Permafrost carbon sink.
Physical factors effecting
Water
Carbon
Oil and gas
Impact on carbon and water
Management strategies
Namib (low latitude desert)
Geomorphic processes
no permenant rivers, one of the driest places in teh world - limited fluvial process
aoelian action main process.
SE trade winds transport sand and control orienation of dunes. Wind erodes fine material from desert planes by deflation.
Landforms
highest dunes in the world up to 300m tall
transverse dunes at right angles to prevailing trade winds
barchans and land dunes
between Luderitz and orange river - streamlined rocks form yardangs
abrasion by wind erodes soft rocks.
inselbergs
Facts
SW Africa along tropic of cancer
temp moderated by Benguela current
fog from this - water to plants and animals
south of walvis bay and to orange river - a=large sand desert. elsewhere plains of gravel and bedrock.
23mm of rainfall.
monthly temps from 11-24
Landscape systems
oldest desert. aridity started 5 mill years ago with benguela current.
sand at least one mill years old
orange river is source of sand. taken onemill years for trade winds o transport the sand 400km north to walvis bay,
inselberg - formed by chemical waeathering, developed over million of year swhen there was more water.
tafoni
ST: movement of sand on dunes up and mini avalanching.
duens move up to 30m per year.
The colorado basin
Water supply issues
dam impounded lake mead -providing water for irrigation and meeting the demands eg LA and Pheonix.
aridity and limited water supplies stopped ED.
Flows of water and sediment
Impact on drylands landforms and landscapes
Facts
630,000 km2
The Colorado Plateau (mid lat des)
Facts
Facts
180mm
34 degree july- 3.9 jan
34-40 deg North
Sparse drainage
SW USA
Main Geomorphic processes
Weathering, mass movement, fluvial action,
freeze thaw-winter-small precip
landforms
Pediment ...
Gently sloping rock platform from retreat of mesas and buttes. Covered with sediment from rock fall
Inselbergs
Parrellel retreat from undercutting the weaker organshale, due to weathering and lateral erosion leads to collapse of de chelly sandstone. Flat surface from resistant cap rock. Weathering in the joints of the sandstone leads to rock fall.
Past twelve mill years- tectonic uplift- surface elevated rivers, cut sharper deep canyon
pediments,screes, butes, messas, canyons
Rivers
rivers cut rock = canyon
landscape system changes
Long term uplift of plateau
millions of years ago during wetter phases rivers disected surfaces exposing sandstones and shale. river erosion - widened valleys - parallel retreat.
ST: small rock weathered by freeze tahw. minro rockfalls after heavy rain. thunderstorns - flash floods- transport sediment through wadis which adds alluvial fans.