“Detailed monitoring of soil moisture provides a view of how our whole Earth system works.”

The Soil Moisture Active Passive (SMAP) satellite mission was launched in January 2015; its main purpose is to acquire global measurements of soil moisture. SMAP partnered with the GLOBE program (Global Learning and Observations to Benefit the Environment), which is an international program where students collect environmental variables in a scientifically methodical way. SMAP readings and maps have various uses in various fields, which include monitoring drought, predicting floods, assisting in crop productivity, and linking water, energy and carbon cycles. The goal of this project is to develop a cost effective, robust, and precise in situ soil moisture sensor that can be easily assembled/built, and calibrated by any K-12 student or educator in the field. Using materials that can be purchased at most local hardware stores, along with an off-the-shelf microcontroller (Arduino type), the sensor was built in order to give results close to the degree of accuracy of known sensors. This built sensor should give us a margin of error of ~2% to that of accurate and expensive moisture sensors. Off the shelf soil moisture sensors use resistance to measure the amount in humidity (moisture) in soil. With the home-made sensor, the magnitude of soil resistance was recorded by measuring the resistivity between the electrodes. Upon confirmation of the home-made sensor being the most robust and the off-the-shelf sensor being the easiest to assemble; implementation of said sensors will be introduced to the GLOBE program in order to begin taking soil moisture readings around the world.


Agriculture | Applied Mathematics | Computer Sciences | Earth Sciences | Forest Sciences | Plant Sciences


Erika Podest

Lab site

NASA Jet Propulsion Laboratory (JPL)

Funding Acknowledgement

This material is based upon work supported by the National Science Foundation through the Robert Noyce Teacher Scholarship Program under Grant# 1546150. Any opinions, finding, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. The research was made possible by the California State University STEM Teacher Researcher Program in partnership with NASA-JPL and NSF Supp 2016.



URL: https://digitalcommons.calpoly.edu/star/368


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