Hydrologic Responses to Draught in the Barton Creek Segment of the Edwards Aquifer
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Hydrologic Responses to Draught in the Barton Creek Segment of the Edwards Aquifer Peter Carlson
description
Peter Carlson. Hydrologic Responses to Draught in the Barton Creek Segment of the Edwards Aquifer. Edwards Aquifer. Includes contributing, recharge, and artesian zones Provides drinking water for 2 million people. Barton Springs Segment . - PowerPoint PPT Presentation
Transcript of Hydrologic Responses to Draught in the Barton Creek Segment of the Edwards Aquifer
Hydrologic Responses to Draught in the Barton Creek Segment of the Edwards Aquifer
Peter Carlson
Edwards Aquifer
Includes contributing, recharge, and artesian zones
Provides drinking water for 2 million people.
Barton Springs Segment
South of Austin: highly visible segment of the Edwards Aquifer.
Watersheds for Stream GagesGenerated watersheds using NED30 data and with the zones of the aquifer.
Downloaded NLADS data from NOAH.
Python ProblemsCould not perform zonal averaging reliably.
1/8 degree grid intersectionsIntersected the watersheds and aquifer zones with a 1/8° grid corresponding with the NLADS data.
Area weighting coefficients for zonal averaging.
Python program to interpret *.asc files without using ArcMap.
Palmer Draught Severity Index
Oct-05 Oct-06 Oct-07 Oct-08 Oct-09 Oct-10 Oct-11 Oct-12
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Axis TitlePD
SI (
Mon
thly
)
PDSI uses temperature and precipitation to estimate soil water supply and demand.
Gage Flow vs Precipition:Separated by PDSI
0 1 2 3 4 5 6 7 8 9 100
50
100
150
200
250
R² = 0.0408558095495033R² = 0.534708217238806
13555: R/C = 0.07
DraughtLinear (Draught)No DraughtLinear (No Draught)
Precip
Gage
Flo
w
0 50 100 150 200 250 300 35002468
1012141618
R² = 0.653848488262123R² = 0.555185408114122
13581: R/C = 0.95
DraughtLinear (Draught)No DraughtLinear (No Draught)
Precip
Gage
• Low correlations between precipitation and gage flow may be due to poor accounting for storm events in precipitation data.• Higher correlation between gage flow and precipitation suggest
that some buffer diminishes the effects of storms on gage flow.
Conclusions
0 0.2 0.4 0.6 0.8 1 1.20
0.1
0.2
0.3
0.4
0.5
0.6
0.7
f(x) = 0.484333331627889 x + 0.0818986910556371R² = 0.844267783936941
f(x) = 0.0519926158777405 x + 0.543304493278196R² = 0.145332349193496
DraughtLinear (Draught)No DraughtLinear (No Draught)
Recharge Area/Contributing Area
R2
• In draught conditions, the recharge zone and the contributing zone respond similarly to precipitation events.
• In non-draught conditions, flow through the contributing zone does not reflect calculated precipitation.
