I. Advancing Development of the Parallel 41 Flux Network for Real-Time Evapotranspiration Monitoring

II. Deployment and Maintenance of Flux Towers in Kansas to be Integrated to the Parallel 41 Flux Networks to Support Multi-State Real-Time Evapotranspiration Estimates

Goal: To expand a multi-state network of eddy covariance flux towers that provide real-time evapotranspiration (ET) estimates used by farmers and other stakeholders.
Partners: University of Nebraska-Lincoln, Kansas State University, LICOR,
The Climate Corporation
Contact: Christopher Neale, Eduardo Santos 

Abstract for UNL-hosted project: The objective of this project is to further augment the Parallel 41 network of eddy covariance flux stations being implemented initially in the Central Plains of the US, by including five additional eddy covariance towers donated by our Industry Partners, The Climate Corporation. The network has been partially established with 2018 and 2019 funding from the IIC with 10 towers located in Iowa (3), Nebraska (5), Kansas (1), and Colorado(1). The 2020 funding will facilitate the installation and operation of five additional towers with at least one to be in Kansas. The support for operating this and other towers in Kansas is being covered through a separate proposal to the IIC. The eddy covariance flux towers will be networked together using the LICOR FluxSuite software app and SmartFlux hardware installed at each tower, that conducts real-time processing and all necessary corrections. These in-field real-time actual evapotranspiration measurements distributed across the central plains along with satellite-based spatial products will be used by water and agricultural crop managers in the participating states as well as farmers and irrigators through online and cell phone apps.

Abstract for KSU-hosted project: The objective of this project is to set up and maintain three eddy covariance (EC)flux towers in Kansas to be integrated to the Parallel 41 Flux Network in the US Great Plains. The purpose of this network is to provide real-time, quality controlled and processed crop and natural vegetation evapotranspiration (ET), an important parameter for irrigation water management and water balance studies in watersheds and groundwater recharge estimations. One of the flux towers will be set up over turfgrass at the K-State Rocky Ford Turfgrass Research Center in Manhattan, KS. The other two towers will be installed in wheat production systems in Central Kansas. On-site flux calculations will be performed using a new flux processing system (SmartFlux 2 System, LI-COR) at the turfgrass and one of the agricultural sites. To ensure the data quality provided to different stakeholders, the SmartFlux 2 System ET estimates will be compared with ET estimates following traditional flux calculation protocols. We will also evaluate the feasibility of using existing flux gap-filling protocols to provide real-time estimates of ET when atmospheric conditions are not suitable for EC measurements. The ultimate goal of this evaluation is to identify measurement and gap-filling protocols that allow near-instantaneous accurate ET estimates. This will minimize data gaps in the Parallel 41 Flux Network improving the ET dataset quality provided to stakeholders.

As farmers and water managers make critical decisions in arid climates, evapotranspiration (ET) is a critical parameter in making efficient water management decision. ET is also difficult to accurately measure. Smart eddy covariance towers can accurately measure evapotranspiration at fixed locations, and the data they generate can be used to validate satellite-based, remotely sensed data.

This project’s objective is to expand and update the network of eddy covariance flux towers along the latitude line 41 north, which runs east to west corresponding to a region of significant food production across the central United States.

Researchers added 10 Eddy covariance towers over 2 years:  3 in Iowa, in 5 in Nebraska, 1 in Kansas, and 1 in Colorado. Enhanced collaboration between Daugherty Water for Food Institute and The Climate Corporation supported irrigation scheduling field trials that used the Spatial Evapotranspiration Modeling Interface (SETMI) remote sensing model in an operational capacity to make weekly or twice-weekly irrigation recommendations on producers’ fields based on calculating a soil water balance, combined with flux tower data. The Parallel 41 webpage provides free, real-time access to the data being processed by the flux towers.

https://parallel41.nebraska.edu/#/ provides free, real-time access to the data being processed by the flux towers. Eventually, users will be able to register and download datasets.