Drought Mapping of the Pedernales Watershed

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

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Month of the Year

PD

SI

Valu

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Data Source: ftp://ftp.ncdc.noaa.gov/pub/data/cirs/drd964x.pdsi.txt

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Month of the Year

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lue

2001

2002

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2004

2005

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2011

Data Source: ftp://ftp.ncdc.noaa.gov/pub/data/cirs/drd964x.pdsi.txt

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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

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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?