case study + climate Flashcards
what is the geography of the river wye
- the river wye is over 150 miles (120 km) long, and is the 5th longest river in the UK, and descends over 700m along its course
what are the management strategies for the river wye to reduce risk of flooding
- vegetation management reduces rates of runoff by increasing surface cover and improving interception storage -the risk of landslides or other mass movement may be reduced by planting trees, which also intercept rainfall and help bind the soil surface together
- afforestation has helped the river wye, by stabilising the slopes which reduces the amount of mass movement
- improved slope stabilisation helps with flooding, as more water can be held in the channel, although this has a knock-on effect downstream for lack of deposition, and therefore increases rates of erosion - decreased natural formation of levees
-Floodplain Zoning
Parts of the floodplain above Hereford are allowed to flood and this reduces the risk of flooding to properties further downstream
what is the human activities affecting river wye
Leisure and tourism including rock climbing, canoeing and kayaking - At Rhayader, the original waterfall was removed when the town’s bridge was built, this left behind small rapids (which are great for canoeists) BUT doesn’t absorb much water or slow the rate of erosion. This leads to higher volumes of water, faster flow rate and therefore, faster erosion by hydraulic action and creation of waterfalls and gorges at Cleddon Falls.
- Humans have built bridges at major points along the course of the river, which has further impacted the natural flow of the river.
-Limestone quarrying has changed the valley’s gradient
what are geomorphic processes of river wye
- much of the rainfall is in winter with little interception by vegetation, leading to rapid river flows and high rates of erosion
- mass movement occurs due to weathering and high rainfall
- freeze-thaw occurs due to fluctuating temperatures in winter, which have created V-shaped valleys and interlocking spurs
- hydraulic action and abrasion helps form the plunge pool of a waterfall, whilst lowering the gradient of the river’s course
- geomorphic processes shape the river, through creating waterfalls in the upper course of the river ( Plynlimon ) , meanders in the middle course,( hereford / hay on wye ) and floodplains in the lower course ( chepstow )
what is the geology like across the river wye
upper course :
what are the sea defence systems at north norfolk coast
- rip rap - large rocks placed in front of a cliff, to protect the coastline by slowing down rate of erosion, and are used at happisburgh
- sea walls - made of concrete, to reflect and absorb wave energy, and prevent erosion of the coastal landscape
- gabions - wire cages filled with stone, to reduce erosion
- groynes - concrete or hardwood barriers, that are placed perpendicular to the coastline, to slow down rate of sediment movement
what are the geomorphic process at north norfolk
geomorphic processes:
- soft, impermeable clay base, with soft, permeable gravel above
- the underlying rock is chalk, which appears in places like hunstanton, and cromer
- the impermeable clay traps water flowing through cliffs, causing it to discharge from the cliff face
- this leads to an increase in pressure in the cliff, reducing the strength of the cliff, which may cause landsliding or slumping, caused by weathering
- as the cliffs are made of soft varied materials, with low resistance, this also means that they are very vulnerable to wave erosion, and mass movements caused by undercutting
- longshore drift operates from east to west, along the stretch of coastline
what are the 4 main strategies to defend coastline
- no active intervention (do nothing) - no planned investment in defending against flooding or erosion, as the cost of defences is worth more than the area
-hold the line - maintaining sea defences, so the position of the shoreline remains where it is
- managed realignment - allowing the shoreline to move naturally, but managing the process, by directing it to certain areas
- advance the line - building new sea defences, as the cost of sea defences is less than the worth of the area
where is norfolk
a county in east of england, with a low-lying coastline
what low impact activities are provided at a small scale caste study
- walking, trekking , climbing and skiing
- visiting penguin colonies - but people must stay at least 5m away from wildlife
wha are the union glacier guidlines
- visiting union glacier is expensie and so guidlines have been enforced for visitors to follow :
- tents are naturally heated by 24 hours sunlight - up to 15 - 21 degrees =. no need for further energy ALSO wooden floor to provide for insulation from snow , solar panels used to reduce need for use of aviation fuel to melt snow for fresh water and heat for showers
- ALE set highest standars for environemnt eg:
- to minimise amount of grey water generates, disinfectant hang del is provided for hand - washing,
- guests are ask to limit shower use to 1 shower eery 2/3 days = conserve water
-all human waste is removed from union glacier camp = carefully contained and removed at the end of the season
what are the cnos of union glacier
has high carbon footprint: planes
- disruptive to wildlife, damaging to habitats
- research have shown that tourist activities have caused change in penguin behaviour
what are the objective of the antartic treaty
- no military operations allowed
- set aside disputes over territory
- freedom for scientific research
- establish it as a nuclear-free zone
- promote scientific cooperation
- protect antarctic environment
- ban activity relating to mineral resources
- to ensure visits must comply with treaty
- preserve historic sites
what are the strengths and weaknesses of antarctic treaty
strengths:
-widely recognised as one of the most successful international agreements
lasted over 60 years with no major problems
promotes scientific research, environmental protection, and prevents military conflicts
weaknesses :
no legal penalties for violating agreements
many believe the treaty should be extended to include more of the southern ocean around antarctica, to cover marine life
if countries disagree about an issue, one country can stop a resolution going forward
what are the issues that tuvalu are facing
tuvalu is threatened by sea level rise, which could swamp the entire island
- increased level of salinisation (pollution by saltwater) affecting soils and crops
– issues with water supply - droughts becoming more common
- coastal erosion affected some island = eroding productive land
how is tuvalu responding with issues
- government campaigning for international community to tackle global warming by reducing carbon emissions - some people already leaving to New Zealland in fear that their home become inhabitable
- some low sea wall have been constructed but they are getting affected by erosino - sea walls are not long term solution
What is climate change?
Climate change refers to long-term changes in average temperatures and weather patterns.
What is the Quaternary period?
The last 2.6 million years, during which temperatures have fluctuated between cold glacial and warm inter-glacial periods.
What is geological fossil evidence?
Different species lived in different climatic conditions, providing evidence of past climate change.
How do ice cores provide evidence of climate change?
Layers of ice within a core can be dated accurately, allowing scientists to calculate past atmospheric temperatures.
What do ocean sediments reveal about past climate?
Oxygen particles trapped within sediments can be used to calculate past atmospheric conditions.
What types of historical records indicate climate change?
Ancient cave paintings, records of extreme weather events, old newspapers, diaries, and written observations.
What was the Little Ice Age?
A period from 1300 to 1870 in Europe characterized by cold climate, crop failures, and increased grain prices.
What are some impacts of the Little Ice Age?
Sea ice surrounded Iceland, crops failed, and people suffered from cold winters and limited food supplies.
What recent evidence indicates climate change?
Global temperature data shows an increase in average global temperatures.
What evidence is there of shrinking ice sheets and glaciers?
Melting ice and retreating ice sheets and glaciers are observed globally due to high temperatures.
What is the change in sea level over the last 100 years?
The average global sea level has risen by 10-20 cm due to melting ice and thermal expansion of ocean waters.
What are Milankovitch cycles?
Cyclical time periods relating to the Earth’s orbit around the sun that affect climate.
What is eccentricity in relation to climate change?
The shape of the Earth’s orbit changes from circular to elliptical, influencing temperature variations.
What does axial tilt refer to?
The tilt of the Earth on its axis, with greater tilt associated with higher average temperatures.
What is precession?
The wobble of the Earth as it spins on its axis, affecting day and night length.
How do volcanic eruptions affect climate?
They release ash and gases that can block sunlight, leading to temporary cooling known as volcanic winter.
What is the role of sunspot activity in climate change?
More sunspots indicate higher solar heat output; very few sunspots were observed during the Little Ice Age.
What is the greenhouse effect?
Solar radiation reaches the Earth, warming its surface, which then emits infrared radiation absorbed by greenhouse gases.
What is the enhanced greenhouse effect?
Increased greenhouse gases from human activities make the natural greenhouse effect more effective at retaining heat.
What are the main sources of CO2 emissions?
Burning fossil fuels, deforestation, and industrial processes.
What are the main sources of methane emissions?
Emitted from livestock, such as cows, and the decay of organic waste.
What are the main sources of nitrous oxide emissions?
Vehicle exhausts, agriculture, and industrial processes.
What challenges does Tuvalu face due to climate change?
Threatened by sea level rise, increased salinisation affecting soils, and issues with water supply.
What are the impacts of climate change in the UK?
Higher temperatures lead to heatwaves, droughts, and wildfires, while higher rainfall increases flooding risks.
How does rising sea level affect the UK?
Increased spending on sea defenses, potential cliff collapse, and loss of agricultural land and beaches.
how does the green house effect work
- heat in form of short - wave solar radiation travels to earths outer atmosphere
- as it passes through atmosphere , some is absorbed by gases and some is reflected from top of clouds
- radiation that reaches the earth warms the surface
- the warmth is released in form of long- wavelength infrared radiation
- the heat is easily absorbed by greenhouse gases in atmosphere
- some heat escapaes to space
what are the worldwide , social impacts of climate change
- people living in vulnerable areas may have to move home/ different country - eg tuvalu
- people may suffer increased frequency of flooding / storm damage
- people lose jobs eg fishing / tourism
- number of environmental refugees - people who lost their home to flooding - will increase
what are the worldwide , economic impacts of climate change
- important world cities eg London / Venice could be affected by flooding
- valuable agricultural land eg bangladesh / vietnam could be affected by flooding
- harbours / ports may be affected = impact fishing / trading
- valuable land / property will need expensive measures of coastal defence
- tourism decreases
what are the worldwide , environmental impacts of climate change
- fresh water source eg wells could be polluted by salty sea water - salination
- damage can occur to coastal ecosystems
- increased flooding / ice caps melting / sea level rise
