Drought Mapping of the Drought Mapping of the Pedernales WatershedPedernales Watershed
CE 394K.3 Term Project
by
Heather Davis
Project BackgroundProject Background
Population Growth:• Competition for water
among agricultural, industrial, commercial, and residential sectors
• Water availability in Texas becoming more scarce
Current Drought:
• Wildfires
• Affected crops/livestock
• Water restrictions
Drought Measure IndicatorsDrought Measure Indicators
• Palmer Drought Severity Index (PDSI)
• Crop Moisture Index (CDI)
• Standardized Precipitation Index (SPI)
• Percent of Normal
• Surface Water Supply Index (SWSI)
Research – How to Proceed?Research – How to Proceed?
Available Usable Data:
• National Oceanic & Atmospheric Administration – National Climatic Data Center (1895-present!)
• University of Nebraska-Lincoln – US Drought Monitor Maps (1999-present)
Palmer Drought Severity IndexPalmer Drought Severity Index
• Standardized to local climate, good for long-term prediction
• Not particularly useful in calculating supplies of water locked up in snow or for short-term forecasts
• Positive numbers reflect rainfall, or an abundance of available water
• Negative numbers reflect drought, or a lack of available water
Palmer Drought Severity Index Palmer Drought Severity Index (PDSI)(PDSI)
• 0 – Abnormally Dry
• -1 – Moderate Drought
• -2 – Severe Drought
• -3 – Extreme Drought
• -4 – Exceptional Drought
Data Source: http://droughtmonitor.unl.edu/dmshps_archive.htm
-8
-6
-4
-2
0
2
4
6
8
10
1 3 5 7 9 11
Month of the Year
PD
SI
Valu
e
Data Source: ftp://ftp.ncdc.noaa.gov/pub/data/cirs/drd964x.pdsi.txt
-6
-4
-2
0
2
4
6
8
1 3 5 7 9 11
Month of the Year
PD
SI
Va
lue
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
Data Source: ftp://ftp.ncdc.noaa.gov/pub/data/cirs/drd964x.pdsi.txt
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-4
-2
0
2
4
6
8
1895 1915 1935 1955 1975 1995 2015
Year
PD
SI V
alu
e
January
February
March
April
May
June
July
August
September
October
November
December
Data Source: ftp://ftp.ncdc.noaa.gov/pub/data/cirs/drd964x.pdsi.txt
-6
-4
-2
0
2
4
6
8
1985 1990 1995 2000 2005 2010
Year
PD
SI V
alue
January
February
March
April
May
June
July
August
September
October
November
December
Data Source: ftp://ftp.ncdc.noaa.gov/pub/data/cirs/drd964x.pdsi.txt
12 Week Animation12 Week Animation
• http://droughtmonitor.unl.edu/12_week.gif
Work to ComeWork to Come
• Statistical analysis of compiled data to assist in drought prediction
• Development of mathematical model to predict oncoming drought
Questions?Questions?