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Water Conservation
Jan KleisslAssistant Professor
Dept of Mechanical & Aerospace p pEngineering, UCSD
OutlineOutline
d l l• Hydrologic Cycle• Water in CA• Losing water Evapotranspiration• Water Module of the Schoolyard Desert• Water Module of the Schoolyard Desert Discovery Project
T d E i– Temperature and Evaporation– Irrigation System– Weather Observations
• DEMROES station visit
Hydrology is the science that treats the waters f h h h i i l i dof the Earth, their occurrence, circulation and distribution, their chemical and physical
i d h i i i h h iproperties, and their reaction with their environment, including their relation to living hi h d i f h d l b hthings. The domain of hydrology embraces the
full life history of water on the Earth.
(M id 1992)(Maidment, 1992)
3
The Hydrologic CycleThe Hydrologic Cycle
The Hydrologic CycleThe Hydrologic Cycle
• For one basin: Precipitation =Evaporation + Transpiration + Overland Flow +Infiltration + Runoff
• Over land, evapotranspiration accounts for 60% of precipitation
• Soil moisture is determined by evaporation. Soil So o stu e s dete ed by e apo at o . Somoisture is important to determine the ratio of runoff to infiltration during a precipitation event u o to t at o du g a p ec p tat o e e tflooding
The California Water Map
PRECIPITATIONPRECIPITATIONAVERAGE PRECIPITATION LEVELS
SNOWPACK – approx. half of surface storage
How do we measure water use?How do we measure water use?
• Water bill: gallons (50 cents/ 200 gallon)
• Evaporation / Rainfall: inchesEvaporation / Rainfall: inches
• Agriculture, Water Resources Management: f (1 f 32 8 1 ll )acre‐feet (1 af = 325 851 gallons). Farmers pay
about 1 cent / 200 gallons or $20/af
• Ocean, Lakes: square miles, storage capacity
E lit• Europe: liter AreaheightVolume =Volume =
Water Inflow DataWater Inflow Datafor 2000, in which there was 97% of average total precipitation
Precipitation 187,742.9
Colorado River 5,349.0
Groundwater: Adjudicated 926.8
U dj di t d 13 926 5Un-adjudicated 13,926.5
Total 14,853.3
Recycled water: Agricultural 28.2
Urban 253.9
Groundwater 43.3
Total 325 4Total 325.4
Inflow from Oregon 1,498.0
Inflow from Mexico 165.6
• In TAF, thousand‐acre‐feetBLUE fl i h GREEN h f d
Ocean Desalination 0.0
• BLUE: flow into the system; GREEN: other sources for consumed water• Numbers from the California Water Plan Update 2005 Volume 3 Regional Reports State Summary, Table 1‐4
California Water Portfolios
InfrastructureInfrastructureCalifornia Water Facts:California Water Facts:
Water SummaryWater SummaryCalifornia receives close to 200 million acre‐feet of water from precipitation and imports
from Colorado, Oregon and Mexico.
http://www.sdnhm.org/exhibits/water/images/charts.gif
Water consumption by useWater consumption by use
Introduction 12
Urban Water UseUrban Water UseI 2000 C lif i iti d b b d b t 8 7 illiIn 2000, California cities and suburbs used about 8.7 million acre‐feet of water
This pie chart gives the percentage of what makes up the US residential water use.
http://planetsave.com/files/2008/02/us‐residential‐water‐use‐609px.gif
Water quantity issues:Water quantity issues: How much water do we use?
U S ti i 2000 178 ll d 1• U.S consumption in 2000: 178 gallons day‐1
person‐1, equals 18% of available freshwater
• Israel = 97%; Saudi Arabia = 164%
• World population expected to double• World population expected to double
in the next 50 years, increasing stress on
water resources
14
Losing Waterg
sLoss
L
Loss
L
Losing WaterLosing Water
• Only fresh water is of use to humans.
• Fresh water follows gravity and flows within aFresh water follows gravity and flows within a watershed. It can be extracted for consumptionconsumption.
• Fresh water leaves the watershed through river discharge ( saltwater) or evaporation.
EvapotranspirationEvaporation: liquid water is converted to water vapor and
removed from evaporating surface (lake river
p p
removed from evaporating surface (lake, river, pavement, soils, and wet vegetation).
Transpiration: vaporization of liquid water contained in plant tissue and the vapor removal to the atmosphere through the stomata.
Evapotranspiration: evaporation and transpiration occurEvapotranspiration: evaporation and transpiration occursimultaneously and there is no easy way ofdistinguishing between the two processes. g g p
17
EVAPOTRANSPIRATION
•Potential Evapotranspiration Epot is evaporation from an extensive f f ( h )free water surface (such as a pan).
•Reference Crop Evapotranspiration ET is evapotranspiration rate•Reference Crop Evapotranspiration ETo is evapotranspiration rate from a reference surface not short of water. The reference surface is a hypothetical grass or alfalfa crop with specific characteristics.yp g p p
California Irrigation Management Information System
C i i d d d di i i h•Crop evapotranspiration under standard conditions ETc is the crop evapotranspiration under standard conditions from disease‐free, well fertilized crops grown in large fields under optimum soil waterwell fertilized crops, grown in large fields under optimum soil water conditions.
ET rates to rememberETo rates to remember
CIMIS
CROP COEFFICIENT Kcc
ETKET =Depends on crop type
occ ETKETclimatesoil evaporationcrop growth stages
Water Module of the Schoolyard Desert Discovery Project
S d l b i i h i h l d• Students learn about science in their schoolyard• Developed by Chihuahuan Desert Nature Park by Stephanie Bestelmeyer
• Funded by NSF through Long Term Ecological y g g gResearch Grant
• Includes: Teacher GuideIncludes: Teacher Guide– Work sheets and Samples– Materials listMaterials list– Bilingual English / Spanish
Water Module OverviewWater Module Overview
• Temperature and Evaporation
• Evaporation in the DesertEvaporation in the Desert
• The Importance of Long‐Term Data
• Biome Climate Comparison
• Local Weather ObservationsLocal Weather Observations
• Water Infiltration
• Irrigation Practices
Water Module
Temperature and EvaporationTemperature and Evaporation
Temperature and EvaporationTemperature and Evaporation(pages 4 ‐ 17)
• Can be used to teach about scientific process ( t t h ll t d t id tif(construct graphs, collect data, identify patterns in collected information, analyze information communicate valid conclusions)information, communicate valid conclusions)
• Can be used to teach about water cycle, di t f th d fi iti fradiant energy from the sun, new definition of
a desert
• Very simple experimental design
The real thing!g
10 days or longer
My Observations of Temperature & Evaporation Data Sheet
Date experiment started: April 6, 2005 Date experiment ended: April 8, 2005Page 6
Location of experiment: south end of parking lot
Time: 12:15 pm My group number: 3
g
Volume of water added (in ml): 253
High temperature on day experiment started (in °C): 15.9High temperature on second day of experiment (in °C): 15.1
Average High Temperature (in °C): g g p ( )15.5 °C
Surface Area of Pan (length in cm x width in cm= cm2) 600.25 (1 inch =2.54 cm)
Class Average Data Table
Group Volume of water added (ml)
Evaporation / surface area
(ml / cm2)
Average high temperature
(ºC)(ml / cm ) ( C)
1 250 0.416 ml/cm2 15.5 ºC
2 256 0.426 ml/cm2 15.5 ºC
3 253 0.422 ml/cm2 15.5 ºC
4 253 0.422 ml/cm2 15.5 ºC
55
6
7
Temperature and EvaporationTemperature and Evaporation
Let’s collect some data !Let s collect some data !
My Observations of Temperature & Evaporation Data Sheet
Date experiment started: April 6, 2005 Date experiment ended: April 8, 2005Page 6
Location of experiment: south end of parking lot
Time: 12:15 pm My group number: 3
g
Volume of water added (in ml): 253
High temperature on day experiment started (in °C): 15.9High temperature on second day of experiment (in °C): 15.1
Average High Temperature (in °C): g g p ( )15.5 °C
Surface Area of Pan (length in cm x width in cm= cm2) 600.25 (1 inch =2.54 cm)
Class Average Data Table
Group Volume of water added (ml)
Evaporation / surface area
(ml / cm2)
Average high temperature
(ºC)(ml / cm ) ( C)
1 250 0.416 ml/cm2 15.5 ºC
2 256 0.426 ml/cm2 15.5 ºC
3 253 0.422 ml/cm2 15.5 ºC
4 253 0.422 ml/cm2 15.5 ºC
55
6
7
Page 7Temperature & Evaporation - Samples
g
Class Temperature & Evaporation Data Sheet
Time: 12:15pm Location of experiment: south end of parking lot
Dates Evaporation / surface area (ml/cm2)
Average high temperature(ºC)
April 6-8, 2005 .443 15.5 ºC
May 9-11, 2005 .444 18.5 ºCy ,
June 8-10, 2005 .491 23.0 ºC
Temperature and EvaporationTemperature and Evaporation(pages 4 ‐ 17)
• So simple that it spurs students to ask their own tiquestions
• Example: How does the color of the screen affect evaporation rates?evaporation rates?
• What other questions could you ask?
• How would you test each question?
Temperature and EvaporationTemperature and Evaporation(pages 4 ‐ 17)
• Other questions that have been tested by students:
– Does the surface (e.g. concrete, grass, etc.) that the evaporation pan is placed on affect the evaporation rate?
– Does the turbidity of the water affect evaporation rates?
– Does the microclimate affect the evaporation rate?Does the microclimate affect the evaporation rate?
– Is the evaporation rate really affected by surface area or is it more influenced by the total volume of water that can be lost?
– Does the humidity affect evaporation rates?
Now students are doingNow students are doing student‐centered inquiry!!!
S h l d D t Di St thSchoolyard Desert Discovery Strengths
Inquiry-based environmental science (easily transforms to student-centered inquiry)
Sh th t i i f !Shows that science is fun!
Locally relevant and up-to-date scientific information
Encourages students with different learning styles and talents
Interdisciplinary
Shows value of long-term data
Determinants of EvaporationDeterminants of Evaporation
• Solar radiation
• TemperatureTemperature
• Relative Humidity / Water vapor deficit
• Wind Speed
Extreme Evaporation during Santa Ana!Extreme Evaporation during Santa Ana!
Temperaturep
The higher the
Water vaporcondensation vaporization
gtemperature, the more energy is
l bl fLiquid water
available for ET.
The higher the temperature, the more water vapor the air can hold.
Humidityy
water vapor
Actualhumidity
pdeficit
humidity
Dry airDry air
(Monteith & Unsworth, 1990)
WindWind
(Allen et al., 1998)(Allen et al., 1998)
Wind reduces the aerodynamic resistance to evaporation
Water Module
Evaporation in the desertEvaporation in the desert
L t’ ll t d t !Let’s collect some data !
Water Module
Irrigation SystemIrrigation System
DEMROESDecision Making using Real time Observations forJan Kleissl Paul LindenDecision Making using Real‐time Observations for
Environmental Sustainability
Planned scope of DEMROES meteorological stationPlanned scope of DEMROES meteorological station network on UCSD campus. Green: existing stations, blue: lamppost stations, red: rooftop stations
MAE and BioEng students assembling a DEMROES station
Measurements*
*
* Air temperature and humidity* Global solar radiation (pyranometer)* Air temperature and humidity* Global solar radiation (pyranometer)* Solar panel temperature, power output* for large arrays: inverter efficiency* One site: rotating shadowband radiometer
* Solar panel temperature, power output* for large arrays: inverter efficiency* One site: rotating shadowband radiometer
** One site: rotating shadowband radiometer* One site: rotating shadowband radiometer
DEMROES G lDEMROES Goals
• Quantify the spatial distribution of meteorological conditions (e.g. sea breeze) on campus( g ) p
• Use the network as a demo and integrative educational and research system for UCSD studentseducational and research system for UCSD students and faculty.
• Inform UCSD energy management system for• Inform UCSD energy management system for building energy conservation and irrigation control.
l l l l• Evaluate solar power potential in coastal environments. Simulate mini‐grid control.
Interested in linking your schoolInterested in linking your school to the DEMROES network?
jkleissl@ucsd.edujkleissl@ucsd.edu
443 527 2740
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