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A satellite platform is one of the major EO (Earth Observation) satellite components because it carries scientific tools that do the measurements and send data back to Earth for analysis. Today’s advanced satellite platform technology allows us to conduct soil moisture measurements that help farmers assess the health of their plants, predict crop yields and flooding, measure how much water a site uses, and so on. We can indeed use ground sensors for the same reasons, but satellite data sources are more reliable and economical. This is especially true when monitoring large remote areas.
How do satellites measure soil moisture?
Satellite soil moisture estimation methods analyze and measure microwaves that the Earth emits or reflects. Most of these methods can monitor only specific areas. And they provide observational data all the time. Yet, since spatial heterogeneity characterizes ground moisture, these methods don’t represent spatial distribution accurately — at least not at larger scales. Therefore, satellites measure land humidity by employing remote sensing technology that provides resolutions for much wider regions. Satellite remote sensing for commercial agriculture gives an advantage while estimating and monitoring large land properties. Remote sensing technology has been used for agricultural analysis purposes ever since 1970.
Some proven satellite methods include the microelectromechanical system (MEMS), soil moisture heat flux sensors, time reflectometry (TDR), and thermo-gravimetry. There’s also the International Soil Moisture Network (ISMN) that offers the highest-quality observations. According to the optical data they receive from satellites, land type, and vegetation, scientists determine the connection between soil moisture and ground temperature in a day. Humidity is then calculated according to thermal data analysis. All this would not be possible without satellite platforms.
What is the most accurate method of soil moisture measurement?
Soil moisture estimation using remote sensing and radar imaging is the most accurate and efficient measurement method today. A satellite platform for soil moisture estimation is equipped with advanced remote sensing technology components that take measurements continuously, almost in real-time. Satellite observations are made after space platform data is sent from remote sensing equipment and images have been collected. As mentioned, the method employed by ISMN provides the most accurate observations — mostly because ISMN covers many platforms and networks, updating its remote sensing collected data regularly. Their remote sensing measurements involve using active sensors with a high spatial resolution on advanced space platforms. Scientists use so-called MODIS sensors to derive vegetation, temperature, and some other variables at the surface ground.
Which soil condition can be best monitored using a satellite?
Ironically, satellite platforms can estimate soil moisture best when the land is actually moist. Different other factors influence platform estimation results. These factors include land characteristics, terrain, vegetation, and climate. There are also changing effects, such as soil depth and rainfall patterns. In semi-arid and arid regions, a satellite platform faces many challenges because it’s difficult to make accurate predictions on how soil moisture is spatially distributed. Thus, it’s also difficult to make vegetation sustainability assumptions about such areas. And one of the main purposes of a satellite platform is helping to determine if the soil condition is optimal for agriculture or growing vegetation. Last, there’s the extreme drought condition that doesn’t make it easy for a satellite platform to estimate land conditions in the region. For this reason, scientists focus on more advanced satellite remote sensing technologies that can analyze and make estimations on deep soil moisture.
How to determine soil moisture?
Satellite platform estimation of soil moisture helps determine if the land is moist enough for agriculture, for example. But note that it only helps for now. Until scientists and engineers develop more advanced space platform equipment for estimating land conditions, ground measurements remain very important for commercial agriculture. However, soil moisture estimation data provided by a spacecraft platform weighs a lot, and without it, ground specialists would not be able to make the most accurate observations. Besides, ground sensors for tracking water and moisture are very expensive and difficult to use. Thus, using a satellite platform that carries optical and thermal sensors for soil moisture estimation is a must when dealing with large agricultural properties. In other words, determining soil moisture is possible only if the satellite platform and ground data are combined.
Ground soil moisture estimation methods are not only costly and challenging, but they also don’t provide the most accurate results. For this reason, scientists have also developed a method that uses a satellite platform for soil moisture estimation. All information collected from both ground analyzes and through satellite remote sensing platforms gives a good picture of actual ground conditions, allowing for accurate yield forecasts. Besides, as new technologies emerge, space platforms become more affordable for commercial use.
