W - 2.5 -> 2.7 Flashcards
1
Q
Houston, Texas:
A
- 4th most populous city in USA (2.3 million)
- located on banks go buffalo bayou river
- economy based on energy industry, biomedical research and aeronautics
- august 2017 - hurricane Harvey caused severe flash flooding - 50 inches rain
- more people die here from flooding than anywhere else in USA
2
Q
what caused UK floods in 2020
A
- a succession of 3 ‘named’ storms - Ciara, Dennis and Jorge
- 350% of typical annual rainfall - creating very were antecedent conditions, saturated soil, overland flow
- Deep low-pressure mid-latitude depressions stalled over the UK in November
- Large areas of the River Severn floodplain have been built on for housing, along with lots of deforestation
3
Q
socio economic impacts
A
- 40 people were evacuated from Ironbridge
- Homes were inundated – damaging furniture and high-values goods
- Factories can be cut-off from infrastructure
- Shop stocks are ruined
- Some homes / shops cannot get flood insurance again.
4
Q
Environmental Impacts:
A
- Floodwater can degrade the soil and ecosystems: :
- Intense flooding can bring eutrophication
- Pollution from sewage: nitrates, chemicals, heavy metals – all degrade aquatic habitats, and poison soil ecosystems (moles, voles, hedgehogs, badgers
- Animals are often cutoff in isolated fields, or drown.
- New crops / seeds cannot be planted / delayed – price of food starts to rise.
5
Q
precipitation
A
- Could be more intense, further around the world
- Tropics will get more rain,
- S-Africa and S Europe will get less
- N Europe – less snow, more rain
6
Q
run off
A
- 1oc rise = runoff 40%
- Accelerated cycles of intense rainfall and less infiltration
- More droughts in between.
- Lakes and reservoirs drying up?
7
Q
evaporation
A
- More in Asia and N America
- More over oceans
- More cloud cover counteracts evaporation
- More productive vegetation (more transpiration)
- Lesson water in soil
8
Q
soil moisture and GW
A
- Depends if precipitation counteracts this.
- GW depends more on human abstraction
9
Q
permafrost
A
- High latitude temperatures increase, permafrost degrades
- Active layer deeper and methane release (affects GW supply and trigger feedback cycle
10
Q
snow/ice
A
- Snow-cover duration falls, spring-melt earlier
- More river water in ST, less in long-term
- More pronounced in high-altitude glaciers
11
Q
thermal expansion
A
of lakes as a result of climate change
12
Q
excess soil moisture
A
lower rice yields + soy beans
13
Q
increased transpiration
A
depletes soil moisture
14
Q
hydropower reservoirs
A
increases GHG emissions - net negative?
15
Q
higher heat in freshwater ecosystems
A
= minimal water flows = changes wetlands by changing breeding/ feeding tendencies
