Water - EQ2 - 5.6 Flashcards
What parts of the hydrological cycle are changing with climate chage
- many processes (precipitation & evaporation),
- flows (inputs & outputs)
- & stores
Define climate change
- refers to the large-scale, long-term shift in the planet’s weather patterns & average temperatures,
- since the 1800s, humans have contributed to the release of CO^2 & other GHGs into the atmosphere,
- causing global temperature rise & long-term changes
What precisely will be increased vs decreased due to climate change in the hydrological cycle
- cc will reduce inputs
- reduce stores
- but may increase outputs
CC impact on inputs & outputs
List the different inputs & outputs that are impacted by CC
- precipitation
- evapo-transpiration
CC impact on inputs & outputs - precipitation
The …. of precipitation may be more important than the ….. in determining the impacts
- mode
- amount
CC impact on inputs & outputs - precipitation
A warmer atmosphere has a greater ….. –> for every 1 degrees celcius, ……..% higher ………………….
water holding capacity
7%
higher atmospheric retention of water
CC impact on inputs & outputs - precipitation
For every 1 degrees celcius, …% higher atmospheric retention of water
7%
CC impact on inputs & outputs - precipitation
For every 1 degrees celcius, 7% higher atmospheric retention of water —> therefore, widespread increases in …… & …….. are anticipated
- rainfall intensity
- frequency
CC impact on inputs & outputs - precipitation
Which areas will be most affected by an increase in precipitation
- tropics & high latitudes
CC impact on inputs & outputs - precipitation
Which areas will be most affected by an decrease in precipitation
10 - 30 degrees N & S of the Equator
CC impact on inputs & outputs - precipitation
How will rising temps affect precipitation
- length & frequency of heatwaves increasing
- icnreasing occurences of drought & water scarcity
CC impact on inputs & outputs - precipitation
snowfall is more likely to be replaced with ….. in …… regions, reducing …..
- rain
- Northern regions
- glacial mass
CC impact on stores - soil moisture
Rises in precipittation leads to ….. in soil moisture & …. ….
- rises
- vice versa
CC impact onstores - soil moisture
What is the overall impact of CC on soil moisture
- uncertain as many factors contribute soil moisture levels & climate as just one factor
CC impact on inputs & outputs - evapotranspiration
Evaporation over large areas of …………………. appears to be …………
- Asia & North America
- increasing
CC impact on inputs & outputs - evapotranspiration
Transpiration is linked to ………….. changes, which in turn are linked to changes in …………………..
transpiration is linked to vegetation changes, which in turn are linked to changes in soil moisture and precipitation
CC impact on stores & flows
List the different stores & flows impacted by CC
- surface runoff & streamflow
- groundwater flow
- reservoir, lake & wetland storage
- soil moisture
- permafrost
- snow
- glacier ice
- oceans
CC impact on stores & flows
It is expected that CC will …… stores & ….. flows
- reduce stores
- increase flows
CC impact on stores & flows
There is more …. needed to be done to establish …… CC & the hydological cycle
- research
- a definite link between
CC impact on stores & flows - surface runoff & streamflow
What is the impact on extreme flows
- More low flows (droughts) and high flows (floods)
CC impact on stores & flows - surface runoff & streamflow
Impact on surface runoff?
Increased runoff and reduced infiltration
CC impact on stores & flows - surface runoff & streamflow
A … degree celcius rise in temperatures could increase surface run off by ….%
- 1 degree celcius
- 40%
CC impact on stores & flows - groundwater flow
What is the impact on ground water flow
- abstraction of water makes impact uncertain
- aquifers depleted through overasbtraction but alos low flow events not reharging store
CC impact on stores & flows - reservoir, lake & wetland storage
What is the impact on reservoir, lake & wetland storage
- changes cannot be conclusively linked to CC
- it appears that storage is decreasing as temperatures increase
- regional variations in lakes 7 reser
CC impact on stores & flows - soil moisture
what is the impact on soil moisture
- possibly little change, with higher precipitation & evaporating cancelling eachother out
- where precipitation is increasing it is likely soil moisture will rise
CC impact on stores & flows - permafrost
What is leading to permafrost degredation
- Changes in physical climate at high altitude, primarily icnreasing air & ocean temperatures are leading to permfrost degredation
CC impact on stores & flows - permafrost
This ……… of the …………… layer is releasing more ………
This deepening of the active layer is releasing more groundwater
CC impact on stores & flows - permafrost
……… released from ……….. lakes may be accelerating change, increasing the …………… effect in a ………. feedback loop
Methane released from thawed lakes may be accelerating change, increasing the greenhouse effect in a positive feedback loop
CC impact on stores & flows - snow
what is the impact
- Decreasing length of snow-cover season
- Spring melt starting earlier –> economic impact - tourism revenue
- A decreasing temporary store
CC impact on stores & flows - glacier ice
What strong evidence is there since the 1970s
- glacier retreat and thinning
CC impact on stores & flows - glacier ice
Why would there be less glacial ice
- Less accumulation because more precipitation is falling as rain
A decreasing store
CC impact on stores & flows - glacier ice
What does less accumulation because more precipitation is falling as rain mean for glacier ice
A decreasing store & negative mass balance
CC impact on stores & flows - oceans
More data on ………… needed
- surface temperatures
CC impact on stores & flows - oceans
possibility of increases in ……….. & rise in frequency & intensity of ………..
- evaporation
- tropical cyclones
CC impact on stores & flows - oceans
……. capacity being increased by ……..
Storage capacity being increased by meltwater
CC impact on stores & flows - oceans
Rising ….. level
sea
What is the IPCC’s predictions for global warming in the next 20 years
- global average temps could exceed 1.5 degrees
- artic is melting quicker than expected
- increased wildfires
Why is it difficult to predict water scarcity
- uncertainty arises because modern scientfic research is unable to make confident predictions about water scarcty
- which is especially difficult in areas with short & long term climate changes
Even if scientists were able to make preditions about water scarcity, there are other ….. to account for
unknowns
Even if scientists were able to make preditions about water scarcity, there are other unknowns to account for, such as…
- possible advances in water technology
- population rise
- global development rise
What are 2 unpredictable things which lack research
- climate change & enso effects impact on draiange basins & water cycles
By 2025, ….. people could be facing water scarcity
1.5 billion
Exemplify how climate change affects on the hydrological cycle can be genralised, but affects would vary globally
- Northern Hemisphere - boreal & tundra climates wetter
- Whereas, much of the world will be drier, esepcially where there are mediteranean climates
It is necessary to distinguish between ….. climate change impacts & the …… of ENSO cycle
- longterm
- short term oscillations
Why is it so difficult to distinguish between enso cycles & climate change
- ENSO cycles result in both extreme flooding & drought in different parts of the world simultaneously
Some world regions are affected by climate change every ……. or …… by changes in atmospheric circulation, one of which is ENSO
Some world regions are affected by climate change every decade or less by changes in atmospheric circulation, one of which is ENSO
Some world regions are affected by climate change every decade or less by changes in ……………….., one of which is ………………
Some world regions are affected by climate change every decade or less by changes in atmospheric circulation, one of which is ENSO
Where does ENSO create uncertainty in water supplies
- Oceania
- South East Asia
- the Americas
When does Southern USA feel water secuirty from La Nino
- October to April
When does North East USA feel water insecurity from El Nino
- December to March
Southern USA experiences water security during….
El Nino
North East USA experiences water security during….
La Nina
What is a greater cocnern than ENSO cycles (arguably)
- the potential impat of short-term climate changes (regardless of ENSO cycles) on global water supplies
What would increase the frequency of ENSO cycles
- if land & sea surface temperatures continue to rise, then it is possible ENSO cycles could become more frequent rather than every 2-3 years
Explain the factors leading to diminishing water supply & increased long-term uncertainty
-SA & Australia climates
- more periodic, unusual climates
- would lead to unreliable rainfall patterns of rainfall
- & failure of monsoons impacting tropical climates
Explain the factors leading to diminishing water supply & increased long-term uncertainty
-increased temperatures
- increased evaporation from surface water & reservoirs
- lowers water levels
- & increases risk of waterborne diseases & cholera
Explain the factors leading to diminishing water supply & increased long-term uncertainty
-evapotranspiration
- increased evapotranspiration
- desiccation of tree stores
Define desiccation
- the process of wet soil drying out and losing moisture to the surrounding environment, which can eventually cause the ground to crack
Explain the factors leading to diminishing water supply & increased long-term uncertainty
-snowfall
- lower snowfall & glacial melt
- threatens inidigenous communitys located in mountain civilisations
