Research Project Mean vulnerability to drought 1990–2005 for wheat production. Vulnerability to drought is low (high) when crop failures are small (big) despite a major (minor) drought, indicated by colors from green to red. (Simelton et al., 2012)

Research questions How do drought frequency, drought severity, and the vulnerability of hay production to drought vary between your counties? What are the most likely causes of the observed pattern in vulnerability?

Question 1 Calculate the standard deviation () of the drought index (DI) for your stations. Specify drought severity categories Category 1: Category 2: Category 3: Create a table showing the frequency of droughts in each category and the average vulnerability index associated with each category

Results table composition County Category 1 Category 2 Category 3 County A % of years Avg VI County B

Question 2 Goal here is to generate plausible hypotheses, not definite answers. Develop a list of factors which might reasonably influence the vulnerability of hay production to drought. Identify county specific data for some of those factors. Create table(s) or figure(s) comparing those factors for your counties.

Obtaining hay production data Go to: http://www.nass.usda.gov/Quick_Stats/ Enter “hay” in the search box at the top of the page. Select: Survey, Crops, Field Crops, Hay, Production, Hay-Production, Measured in Tons, Total, County, Oklahoma, (your counties), (all available years), Get Data Click “Spreadsheet” on the top right-hand side

Obtaining soil moisture data Not possible Obtain sensor output which must be converted to soil moisture (volumetric water content) Go to www.mesonet.org Click on the “Weather” tab Click on “Past Data & Files” on the left-hand side Click on “Daily Data Retrieval” in the second row on the right-hand side Select dates, stations, and variables (TR05, TR25)

Converting Mesonet sensor output to soil moisture Download the necessary soil properties from the class webpage Use the appropriate equations in Scott et al. (2013)