Welcome to the ETool Project

We are currently working to better understand how agriculture influences the Upper Midwestern hydrologic cycle. Particular emphasis is being placed on constraining evapotranspiration (ET) from agricultural systems and the region using a variety of measurements and modeling techniques. A major goal of this project is to use the research capacity established to support scientific inquiry and to develop a set of resources, collectively known as ETool, to support farm-level water management decision-making. One of the most challenging aspects of irrigated agriculture is estimating crop ET. ETool will address this challenge by providing:

  • Real-time, high spatial resolution actual ET estimates
  • A high resolution almanac of ET for each day of year
  • Locally derived crop coefficients

Real-time ET

Calculating a water budget for irrigation scheduling requires knowledge of water inputs, outputs and storage. The most difficult part of the water balance to accurately estimate is ET because sophisticated instrumentation and technical expertise are required. An emerging issue that will be faced by Minnesota irrigators in the coming years is enhanced convective storm activity. This will intensify rainfall events, and despite projected increases in average precipitation, increase the likelihood of transient drought. The high variability of convective storms in both space and time will make irrigation scheduling an even more challenging proposition.

Our high resolution ET maps in ETool will provide producers with real-time actual ET. The figure below is an example of the model output that will be made available in real-time. Further, we are developing an interactive calculator for getting location specific precipitation and ET forecasts. The figure below shows an example of the calculator we are testing and will make available soon. Producers will be able to select a location on the map near their fields to obtain an up to date ET estimate. This resource will increase producer access to ET estimates; and simplify and increase the accuracy of water budget calculations for irrigation scheduling.

Download the ETool_Calculator here. Follow these instruction for installation on your PC/windows computer.

  1. step 1 coming soon
  2. step 2
  3. step 3

evaporation and precipitation forecast

We will use state-of-the art models to predict meteorology and land-atmosphere energy and water exchange. The Weather Research and Forecasting (WRF) model will be used to describe meteorological fields, while the Community Land Model (CLM) will represent the energy and water exchange between the land and atmosphere. A combination of LiDAR and USDA crop data layers will be employed to describe the land-use within the model. Meteorological boundary conditions will be derived from observational networks and operational NOAA forecasts.

Model Configuration

* All latest and historical ET and precipitation forcast links will open a PDF in a new tab or window.

graphic map showing model configuration location information

WRFV3.5.1

  • Minnesota State 3 km * 3 km

Initial condition and Boundry conditions:

  • Global forecasting system (GFS)
  • 2014/4/30/06UTC 00h-192h forecast
  • 0.5 degree * 0.5 degree

Parameterization schemes

  • Microphysics
  • WRF Single-Moment 3-class scheme
  • Radiation physics
  • Longwave: RRTM scheme
  • Shortwave: Dudhia scheme
  • Land-surface physics
  • Noah Land Surface Model
  • Boundary-layer physics
  • Yonsei University scheme
  • Cumulus physics
  • Kain-Fritsch scheme

24h Evaporation 48-72h

graphic showing 24-hour evaporation in millimeters focusing on Minnesota

"Download the latest ET and precipitation forecast", (Sept 11 - Sept 18, 2016)

Historical Forecast, 2016

"Historical ET and precipitation forecast", (Sept 04 - Sept 11, 2016)

"Historical ET and precipitation forecast", (Aug 28 - Sept 04, 2016)

"Historical ET and precipitation forecast", (Aug 21 - Aug 28, 2016)

"Historical ET and precipitation forecast", (Aug 14 - Aug 21, 2016)

"Historical ET and precipitation forecast", (Aug 7 - Aug 14, 2016)

"Historical ET and precipitation forecast", (July 31-Aug 7, 2016)

"Historical ET and precipitation forecast", (July 24-July 31, 2016)

"Historical ET and precipitation forecast", (July 17-July 24, 2016)

"Historical ET and precipitation forecast", (July 10-July 17, 2016)

"Historical ET and precipitation forecast", (July 03-July 10, 2016)

"Historical ET and precipitation forecast", (June 26-July 03, 2016)

"Historical ET and precipitation forecast", (June 19-June 26, 2016)

"Historical ET and precipitation forecast", (June 12-June 19, 2016)

"Historical ET and precipitation forecast", (June 05-June 12, 2016)

"Historical ET and precipitation forecast", (May 29- June 05, 2016)

"Historical  ET and precipitation forecast", (May 01- May 08, 2016)

"Historical ET and precipitation forecast", (May 15- May 22, 2016)

"Historical ET and precipitation forecast", (May 22- May 29, 2016)

Historical Forecast, 2015

"Historical ET and precipitation forecast", (May 24-31, 2015)
"Historical ET and precipitation forecast", (May 31-June 7, 2015)
"Historical ET and precipitation forecast", (June 7-14, 2015)
"Historical ET and precipitation forecast", (June 14-21, 2015)
"Historical ET and precipitation forecast", (June 21-28, 2015)
"Historical ET and precipitation forecast", (June 28- July 5, 2015)
"Historical ET and precipitation forecast", (July 5-12, 2015)
"Historical ET and precipitation forecast", (July 12-19, 2015)
"Historical ET and precipitation forecast", (July 19-26, 2015)
"Historical ET and precipitation forecast", (July 26-Aug 02, 2015)
"Historical ET and precipitation forecast", (Aug 09-Aug 16, 2015)
"Historical ET and precipitation forecast", (Aug 16-23, 2015)
"Historical ET and precipitation forecast", (Aug 23-30, 2015)
"Historical ET and precipitation forecast", (Aug 30 to Sept 06, 2015)
"Historical ET and precipitation forecast", (Sept 06-13, 2015)
"Historical ET and precipitation forecast", (Sept 13-20, 2015)
"Historical ET and precipitation forecast", (Sept 20-27, 2015)

"Historical ET and precipitation forecast", (Sept 27-Oct 4, 2015)

Historical Forecast, 2014

"Historical ET and precipitation forecast", (May 1-6, 2014)
"Historical ET and precipitation forecast", (May 05-11, 2014)
"Historical ET and precipitation forecast", (May 11-16, 2014)
"Historical ET and precipitation forecast", (May 18-25, 2014)
"Historical ET and precipitation forecast", (May 25-June 1, 2014)
"Historical ET and precipitation forecast", (June 1-June 8, 2014)
"Historical ET and precipitation forecast", (June 8-June 15, 2014)
"Historical ET and precipitation forecast", (June 15-June 22, 2014)
"Historical ET and precipitation forecast", (June 22-June 29, 2014)
"Historical ET and precipitation forecast", (June 29-July 7, 2014)
"Historical ET and precipitation forecast", (July 7-July 13, 2014)
"Historical ET and precipitation forecast", (July 13-July 20, 2014)
"Historical ET and precipitation forecast", (July 20-July 27, 2014)
"Historical ET and precipitation forecast", (July 27-Aug 03, 2014)
"Historical ET and precipitation forecast", (Aug 03 - Aug 10, 2014)
"Historical ET and precipitation forecast", (Aug 17 - Aug 24, 2014)
"Historical ET and precipitation forecast", (Aug 24 - Aug 31, 2014)
"Historical ET and precipitation forecast", (Aug 31 - Sept 07, 2014)
"Historical ET and precipitation forecast", (Sept 07 - Sept 14, 2014)
"Historical ET and precipitation forecast", (Sept 14 - Sept 21, 2014)
"Historical ET and precipitation forecast", (Sept 21 - Sept 28, 2014)
"Historical ET and precipitation forecast", (Sept 28 - Oct 05, 2014)
"Historical ET and precipitation forecast", (Oct 05 - Oct 12, 2014)
"Historical ET and precipitation forecast", (Oct 12 - Oct 19, 2014)

"Download the latest ET and precipitation forecast", (Oct 12 - Oct 19, 2014)

Evaluating the Forecasts

The forecasts from July and August (2014) were considered in this analysis. Accumulated precipitation through 3 days (short-term), and from 4 through 7 days (long-term) were calculated for the model and observations. We compared accumulated precipitation over several days because the model output is for a 24 hour period ending at midnight, while manual observations are typically recorded for a day ending at 0700 or 0800 hrs. Accumulating over several days minimizes the impacts that these discrepancies have on model evaluation. On average, short-term predictions deviated from observations by less than 10 mm for all of Minnesota, and less than 5 mm for a majority of the state, in particular latitudes south of 46.5 degrees N (a). Biases in short-term predictions were near-zero for most latitudes in the state south of 46.5 degrees N (c), indicating a lack of systematic errors. Long-term forecasts were subject to larger errors that on average overestimated precipitation (b & d). The high degree of model skill for short-term precipitation predictions for the intensively farmed parts of the state is encouraging from the perspective of irrigation scheduling. The largest errors in the forecasts were in areas that are a mix of wetlands, lakes and forest. We speculate that model is over-amplifying water recycling in these areas.

graphic showing forecast analysis