Case studies for Paper 2 Section A 'water and carbon cycles' Flashcards
State the case study and location used for a complex river regime
River Po, Italy
Why is the River Po an example of a complex river regime?
It has two peaks during a year (one in May and one in November) and two troughs (One in January and one in August).
Which river do humans influence?
Colorado River, Arizona, USA
What month is peak rainfall for the Colorado river, and what type of rainfall causes intense rainfall? What do storms lead to?
August due to intense storms from convectional rainfall. Storms lead to flash flooding, due to infiltration excess overland flow or Hortonian flow.
How have humans influenced the Colorado river?
Construction of the Hoover dam in 1936
Before the Hoover Dam construction, what was the fluctuating discharge?
500cfs to 100,000 cfs
What did the Hoover Dam construction do to the regularity of discharge?
Discharge became regular with less extreme fluctuations after construction.
After the Hoover Dam construction, what was the fluctuating discharge rate?
5,000 to 30,000cfs
What did humans do downstream of the Colorado River?
Humans regulated stored water from Lake Mead
Where does orographic rainfall affect? Gives examples?
Orographic rainfall affects upland areas such as the West of England, including the Brecon Beacons, Dartmoor and Exmoor.
How many mm does precipitation exceed in upland orographic areas?
2000mm
Which areas are affected by convectional rainfall? Give examples?
Convectional rainfall affects equatorial regions. Tropical rainforests like the Amazon are affected.
Which areas are affected by frontal rainfall? Give examples?
Frontal rainfall affects the UK due to latitude. Warm tropical air collides with cold Polar air along the Polar Front.
Name and year the case study for an intense storm with prolonged rainfall
Boscastle August 2004
What category storm caused the Boscastle flooding?
Category 2 on the Saffir Simpson scale
Why was the storm over Boscastle so powerful? How many metres did the air rise?
Warm air travelled over a large fetch from the Atlantic, rising 400m over Bodmin Moor?
What type of rainfall caused by the storm caused Boscastle flooding?
Orographic rainfall
Which other type of rainfall affected Boscastle apart from Orographic? Explain…
Boscastle was located at a convergence zone as two air masses moved in opposite directions – frontal rainfall
How many mm of rain fell over Boscastle over what time?
75mm in two hours
Give the name of the river that rose in Boscastle? How much did it rise by? What were the direct impacts? Why was there lots of river discharge?
The Valencie River rose 2m causing 30 vehicles to be washed in the harbour. The river has a low catchment areas so low interception and impermeable geology. Steep slopes.
Which case study river do we use for snowmelt?
Red River of Fargo 2009
How many metres did the Red River of Fargo rise by?
13m
What caused flooding the The Red River of Fargo? What year?
2008-2009 winter had high snowfall and frozen ground, followed by unusually high temps and rapid snowmelt.
Describe the study in the UK which describes the affects of deforestation?
One study in mid-Wales found rainwaters infiltration rate into soil was 67x higher under trees than under sheep pasture
When is a drought recognised between countries? Give examples?
In Libya, droughts are recognised after two years without rain, compared to the UK which defines a drought as a period of at least 15 consecutive days where no more than 0.2mm rain falls.
Name the case study for the seasonal drought variations?
The 1976 UK drought
What had to happen as a result of the 1976 drought?hint. industry and £
Industry was forced to reduced output by 50%
9 pints of water required to make 1 pint of beer
40 gallons for 1 newspaper.
Food prices increased due to crop failure
Name the American case study regarding climate change and drought + depletion of aquifers?
Megadrought in western USA
Define megadrought
A multi-decade event that contains periods of high severity that last longer than anything observed during 19th/20th century
Since 2000, how much did Western USA increase by temperature? How does this compare to the global increase?
Since 2000 western USA has increased by 1.2 degrees – the world has increased by 1.1 since 80’s.
Name the lakes that Shrunk during the US’ megadrought
Lake Powell and Lake Mead shrunk
Where did the American people turn to for a source of water during the megadrought? What % of water goes towards agriculture? How many farmers lost job?
They relied on groundwater aquifers. Agriculture accounts for 80%. 30,000 farmers lost jobs
Give the name of the case study used for depletion of aquifers that isn’t the US megadrought?
Egyptian potato farming
Give the name of the aquifer regarding depletion and management of aquifers
California’s Central Valley Aquifer
What fraction of fresh food is produced in California’s central valley?
1/3
In 2013, how many water wells were permitted for water extraction?
2,500
In million acre-feet, how much did water levels drop and from what years? California
50 million acre-feet from 1962 to 2015
Name the valley involving an artificial aquifer recharge study
California’s Pajaro Valley
What % of groundwater supplied California’s freshwater?
Groundwater supplied 85% of freshwater
Describe the artificial recharge project used in California’s central valley. Include water cycle terminology e.g. percolation and porous
Artificial recharge captures excess runoff and diverts water into recharge basins or canals. These basins have porous bases that allow the captured water to percolate down to the aquifer.
What’s the study we use for rising groundwater?
London basin
Describe the London Basin? How many metres is the aquifer located below central London?
The London basin contains a major aquifer, located 60m below central London.
What process has changed the demand for water? Name industries dependant on water? What did demand mean for groundwater levels?
Industrialisation in the 19thy century increased water demand, for water intensive industries like brewing and paper production. This declined groundwater level.
Which other process affected groundwater levels that isn’t industrialisation? How has this affected the aquifer?link to london basin
De-industrialisation reduced demand for water. Since 1970’s the aquifer has started recharging at a rate of 3m annually
Which sea involves surface water extraction, human causes of water deficit
Aral sea
What % of the seas original value is present
10%
What chemistry linked characteristic changed as a result of Aral sea reduction?
Salinity increased from 0-100%
What happened to the climate as a result of the Aral sea reducing in size?
The number of days above 40 degrees had doubled in the Aral sea region
What has been done to increase water levels of the Aral sea? How much has been spent?
$80m world bank money to construct Kokaral dam – 2000 tonnes fish caught annually
Name the case study regarding deforestation and palm oil plantation
Borneo, Indonesia
How has logging and and palm oil plantations affected Borneo? Since what year?
Since 1950 Borneo has lost half of its TR for logging and palm oil plantations
How much carbon do primary forests store per hectare compared to palm oil plantations?
Primary forests store 300 tonnes of carbon per hectare, compared to 30 tonnes per hectare in palm oil plantations
How much rain does a TR receive annually compared to the UK?
A TR receives 2000-4000mm rain annually // the UK gets 200-400mm
What key geographical term does deforestation cause in places like Borneo?
SAVANNAHRISATION – prevents forest recovery – dry climate
The palm oil industry has resulted in what in Indonesia?
land grabs
What did the company promise the indigenous community? what companies were supplied by this company?
Company promised ½ profits to its indigenous community. They never received anything. Supplies companies like Johnson & Johnson and Kellogg’s.
For afforestation, what did Brazil sign in 2016 to increase this process? How much did they promise to reduce emissions by?
In 2016 upon signing the Paris agreement, Brazil pledged to voluntarily reduce CO2 emissions by 43% by 2030.
Which organisation are planting trees and how many?
Ecosia are planting 1 million trees
Name the three types of temperate grasslands around the world
The prairies of plains of USA and Canada
The Steppes of Eurasia from Ukraine to Mongolia
The Pampas of Argentina and Uruguay
Name the case study for drought and soil erosion
The Dust Bowl of 1930’as Mid-West USA
How many acres were affected by the dust bowl case study? which states?
Affected 100 million acres centred on Texas and Oklahoma
What was the American dust bowl case study worsened by?
Poor farming practice
What were the implications of the Dust Bowl case study? Name two for environment and people
Millions of tonnes of top soil eroded by wind
2.5 million abandoned farms
Name the case study for peatland management and restoration
Fenn’s Whixall and Bettisfield Mosses, Shropshire
How many gigatonnes of carbon do global peatlands hold?How does this compare to forests?
Global peatlands contain at least 550 gigatonnes of carbon—more than twice the carbon stored in all the forests in the world.
How much of the earths surface to peatlands take up and how does this relate to carbon stores?
Peatland account for just 3% of the world’s soil surface, yet hold nearly 30% of soil carbon
What two factors facilitated peatland extraction in Whixhall Moss?
facilitated by two transport developments: the Llangollen Canal opened in 1804; a railway that was laid across part of the Moss in 1863.
Name three management strategies of a peat bog
Bunding: Bunds reduce the flow of surface runoff and help keep more precipitation on the site.
Dams and plastic piling: These strategies reduce run of from old drainage ditches and the loss of water from through flow.
Sphagnum moss planting: Sphagnum can store 20 times its own weight in water so will retain rainwater on the site.
