State Water Resources Research Institute Program
Project ID: 2010OK184B
Title: Drought monitoring: a system for tracking plant available soil moisture based on the Oklahoma Mesonet
Project Type: Research
Start Date: 3/01/2010
End Date: 2/29/2012
Congressional District: 3
Focus Categories: Drought, Agriculture, Water Quantity
Keywords: drought, soil moisture, Mesonet
Principal Investigators: Ochsner, Tyson; Basara, Jeffrey (University of Oklahoma); Fiebrich, Chris; Illston, Bradley (Oklahoma Climatological Survey); Sutherland, Albert (Oklahoma State University)
Federal Funds: $ 25,000
Non-Federal Matching Funds: $ 57,352
Critical State water problem
Real-time drought monitoring is essential for early detection and adaptive management to mitigate the negative impacts of drought on the people, economy, and ecosystems of Oklahoma, and improved drought monitoring is a key need identified in the 1995 Update of the Oklahoma Comprehensive Water Plan. Drought impacts can be severe in Oklahoma. For example, the 2006 drought cost the state's economy over $500 million from lost crop production alone. While drought monitoring is critical to Oklahoma's resource managers, it is hampered by a lack of data on a crucial drought indicator: plant available water. Crop yield losses and, by extension, the economic impacts of drought, are strongly linked to plant available water. Plant available water is the amount of soil moisture currently in the profile which is available for plant uptake. Some water is held so strongly by the soil that it is not available to plants. Cumulative rainfall data alone are poor predictors of drought impacts, because costly short term soil moisture deficits can occur in years of average or above average rainfall. At the first signs of drought, resource managers need reliable information on the available reserves of soil moisture to enable effective adaptations (e.g. crop marketing contracts, cattle stocking rates, hay purchases, fertilizer rate adjustments).
This need can be met by building upon the existing capabilities of the Oklahoma Mesonet. The Mesonet is the world's leading automated weather station network providing continuous, real-time data from 120 locations across the state. These stations possess existing soil moisture sensors but offer no measure of plant available water. The plant available water depends, not only on the soil moisture, but also on site-specific properties of the soil. Using funding from this program received in March 2010, we are completing the steps necessary to measure those soil properties and couple them with Mesonet sensor data to produce prototype plant available water maps.
Project objectives and methods
The objective of this proposal is to bring to completion a first-generation drought monitoring system for Oklahoma based on plant available water. The specific aims are: (1) to develop a scientifically-sound procedure for interpolating plant available water between Mesonet sites, (2) to create and release a new daily plant available water map for drought monitoring in Oklahoma, and (3) to discover the similarities and differences between plant available water and other significant drought indicators (preliminary work for leveraging future outside funding).
Results and benefits
This monitoring system will provide resource managers with reliable information on the remaining reserves of plant available water enabling them to adapt their management strategies. The research and development proposed here are essential to bring to completion the world-class drought monitoring system toward which we have made great progress using the funds awarded here last year.
Progress/Completion Report, 2010, PDF
Progress/Completion Report, 2011, PDF