Dutch start-up analyses the earth’s microwave data

Coming from a background of climate research and with experience gathered at, amongst others, the VU University of Amsterdam and the NASA Goddard Space Flight Centre, Richard de Jeu, founder and CTO of Dutch start-up VanderSat, started his company in 2015.

The average soil moisture content in 2016 of an area East of Calgary, Canada. – Photo: VanderSat

Why use microwaves?

De Jeu wanted to make impact with soil moisture information from satellites outside the scientific community. “These satellites provide information about water, which accounts for 85% of the world’s crop failures. Getting a clear view of the water situation globally makes sense for this reason.” The solution according to VanderSat are microwaves because they eliminate the disadvantages of existing satellite imagery: cloud cover and optical, non-soil-penetrating measurements.

When thinking microwaves, don’t get confused since it has nothing to do with the food preparing microwave. The technology uses the microwaves emitted by the earth’s surface as well as any object, including plants, on it. Microwaves are just a part of the electromagnetic spectrum, similar as the visible infrared and near infrared (NIR) domain. Supposedly, not too many companies focus on using the microwaves as yet.

A comparison of soil moisture content in June over 3 consecutive years in the Dutch Province Overijssel. 2016 was relatively wet whilst in 2017 there was a (severe) moisture deficit.

Advantage of microwaves: Soil penetrating

One of the advantages of microwaves is that cloud cover does not influence nor filter the measurements. Another advantage VanderSat says, is that the data can be used to ‘look into’ the soil to a depth of about 5 to 10 centimetres. And since these measurements are done and recorded on a daily basis, the evolvement of the data can be used to accurately predict or interpolate the data to a depth of about 1 metre. This means that farmers can remotely get insight into the soil temperature and soil moisture content of their fields, anywhere on earth, to a depth of 1 metre! Plant temperature and moisture content can also be measured.

Farmers can monitor fields in a consistent way

It’s not that the company owns satellites or so, it has developed a patented methodology to accurately interpret the microwave data from the NASA satellite SMAP, the Sentinel Constellation, the SMOS satellite of the European Space Agency and from the GCOM-W platform of the Japanese space agency JAXA. European farmers might be slightly disappointed in the current resolution of the data (100×100 m or one hectare), but the daily measurements are said to give them an opportunity to monitor their fields in a consistent manner. In addition, VanderSat says competitors don’t get much further than a resolution of 25kmx25km. In near future, the company aims at a resolution of 10×10 metres.

Drenthe is the neighbouring province to the North of Overijssel. There’s similarities in soil moisture content over the 3 years pictured.

Retrieving data from16 years ago

Some advantages VanderSat sees compared to remote sensing by manned and unmanned planes and helicopters, is that satellites offer global year-round data and because of the known satellite constellations, it is possible to accurately retrieve data dating up to 16 years back. Data processing also takes less time and effort and this makes the technology up to 1,000 times cheaper than comparable technology (i.e. UAV’s or sensors on the ground). The solution isn’t an offer to farmers directly, but, if available, through partners like cooperatives and companies already offering services and products to farmers.

Late last year, the Horizon 2020 programme of the European Commission awarded VanderSat with funding amounting to € 1.34 million ($ 1.6 million). The grant is part of Horizon 2020’s small and medium-sized enterprises instrument, which has around € 1.6 billion ($ 1.9 billion) available between 2018 and 2020 and has funded around $ 100 million worth of projects so far.