Climate Change and Water Resources Flashcards
Methods of monitoring the changing climate
- Temperature and Energy
o Surface Temperature
o Ocean Heat - Atmospheric Composition
o Atmospheric CO2 - Ocean and Water
o Ocean Acidification
o Sea Levels - Cryosphere-frozen water part of the earth system
o Glaciers
o Artic and Antarctic Sea Ice Extent
Which variable of temperature and CO2 concentration are leading and lagging- what has this been used to argue
Temperature=Leading
CO2 Concentration=Lagging
This has been used as evidence that climate change doesn’t exist
But as temperatures rise oceans release CO2- positive feedback loop
Who are the IPCC and what is their role
IPCC= Intergovernmental Panel on Climate Change
Established in 1988 with the initial task of preparing a review and recommendations regarding the knowledge of the science of climate change, the social and economic impact of climate change and potential response strategies
What are GCMs and RCMS
GCM= Global Climate Model
RCM= Regional Climate Model
What is UKCP18 based on
-Provides probabilistic projections for 5 scenarios
-Based on RCPs- representative concentration pathways
Factors controlling evapotranspiration
-Temperature
-Solar Radiation
-Wind
-Humidity
-Season- plants stage of growth
-Soil- degree of saturation
What is PET and AET, when are they equal
PET= Potential Evapotranspiration
AET= Actual Transpiration
PET=AET, when soil is fully saturated. Therefore SMD=0
AS SMD increases, AET decrease
How can PET be obtained
-From times series for a specific location, gridded data for 5km squares
-Based on a reference crop
-Estimated from latitude and time series of temperature
How is climate change going to effect groundwater recharge
-A rise in temperature will lead to increased evapotranspiration therefore less water making it to groundwater
-Winter rainfall more important than summer rainfall. Increase in water recharge, although groundwater flooding more likely. Change in summer recharge negligible, as any rain that does occur is used to replenish SMD rather than recharging groundwater
-Potential recharge will be concentrated in fewer months
Decreases in September and
October due to hotter dryer
summers which delay the
start of the recharge season
(due to greater SMD)
Recharge greater from
November to February
Recharge more spatially
variable in spring
How does recharge vary throughout the year
November-February- precipitation exceeds evapotranspiration and soil moisture is recharged
March-May-precipitation>evapotranspiration, there is now water surplus. The water is now available to supply rivers
May-July- evapotranspiration now greater than precipitation , soil moisture is being utilised
August-October-Evapo>precipitation. During the second half of the summer there is a soil moisture deficit
SMD start occurring as soon as AET>rainfall
