This fall scientists at the University of Nebraska, with partners at
Google, Inc. and the University of Idaho, introduced the latest
evolution of METRIC technology—an application called EEFLUX, which will
allow anyone in the world to produce field-scale maps of water
consumption.
METRIC processes satellite images to make digital maps, and is
currently being used by water managers in 15 states to track
agricultural water use. EEFLUX will put this information directly into
the hands of farmers by allowing them to check water-use maps in near
real-time on any mobile device that has web access.
“The use of satellite imagery provides the means to monitor the
agricultural water consumption over every square foot of land surface,“
said Ayse Kilic, a professor in the department of civil engineering and
school of natural resources at the University of Nebraska.
That
imagery comes from the Landsat satellites, whose thermal band data
allows water specialists to measure the amount of water evaporating from
the soil and transpiring from a plant’s leaves—a process called
evapotranspiration (ET).
This process cools the plant down, so irrigated farm fields appear
cooler (bluer) in infrared satellite images. The spatial resolution of
Landsat’s thermal imagery, combined with the Landsat data for other
spectral bands, allows experts and farmers alike to see water
consumption for individual fields.
“With Landsat 7, the Landsat user community began to see the
importance of thermal infrared data for water management,” said Jeffrey
Masek, Chief of the Biospheric Sciences Laboratory at NASA's Goddard
Space Flight Center in Greenbelt, Maryland. “So in 2009 the Thermal
Infrared Sensor (TIRS) was added to the Landsat-8 mission payload.
Water managers can track the effectiveness of various water
conservation projects with METRIC because it provides a new level of
detail: from field to field, crop to crop, and year to year. Also,
Landsat satellites have collected thermal data since 1984 so that water
consumption under existing conservation practices can be compared with
that occurring more than 30 years ago.
“It’s really helped us from a time–frame perspective,” said Duane
Woodward, an engineering hydrologist at the Central Platte Natural
Resource District of Nebraska. “1997, for example, was one of the first
ET years. We did 2007, 2002, 2011, and now we’re doing 2013. So you
really want to look at how its changing year in and year out.”
METRIC was developed by remote sensing analysts Bill Kramber and Tony
Morse, from the Idaho Department of Water Resources, who in the early
2000s teamed up with Rick Allen, from the University of Idaho, to
develop a more holistic solution to water management.
So far, METRIC’S latest application, EEFLUX, has been introduced to
the California Department of Water Resources, the California Water
Control Board, and the World Bank. “Having water consumption maps
produced quickly on Smartphones has been everyone’s dream,” said Kilic.
“In two years time we hope to see all farmers watching their fields from
their phones and scheduling irrigations. EEEFlux is making Landsat the
evapotranspiration satellite.”
Last Updated: Oct. 14, 2015
Editor: Karl Hille