The Copernicus program headed by the European Commission (EC) in partnership with the European Space Agency (ESA) will launch up to twelve satellites, the so called “Sentinels” for earth and environmental observations until 2020. Within this satellite fleet, the Sentinel-1 (microwave) and Sentinal-2 (optical) satellites deliver valuable information on agricultural crops. Due to their high temporal (5 to 6 days repeating time) and spatial (10 to 20 m) resolutions a continuous monitoring of the state of agricultural crops becomes possible. The open data policy offers great opportunities for the operational integration of remote sensing data into agricultural practice.

In April 2014 and 2016 the technical identical Sentinel-1A and -1B satellites have been launched. The radar satellites operate with C-Band (λ~6 cm) and two polarizations (VH, VV) resulting in a spatial resolution over land of nominal 10 m. Combining the orbits of both satellites will result in repeating times of 6 days at equatorial line. In Germany, the revisit time is 4 days even with one satellite only. With its cloud penetrating radar, the Sentinel-1 satellites are very predictable in data availability, which has been the major drawback of the use of remote sensing in agriculture in the past. The high revisit times allow the detection of the phenological stages of different crops, which helps to produce crop type classifications with high accuracy. It has been difficult to distinguish cereals (e.g. barley, rye and wheat) by optical systems so far but this new strategy will render it possible. Also important dates in agricultural management (soil management, harvest dates) can be identified on a field level.

In June 2015, the multispectral Sentinel-2 satellite has been launched. This satellite offers a good spectral resolution with 10 bands and spatial resolutions of 10 to 20 m. This spectral setup helps to retrieve quantitative vegetation parameters like above ground fresh or dry biomass and leaf area index, which serve as input variables to spatial crop growth models. Also a technical identical twin satellite Sentinel-2B is scheduled for launch in 2016. Combining the orbits of both satellites will result in revisit times of 5 days at the equatorial line.

At submission date of the paper, only few cloud free Sentinel-2 images could be acquired for the region of Braunschweig. Also a proper atmospheric correction is not available at the moment, so due to that reasons this paper focused mainly on Sentinel-1A data.

Radar backscatter signatures for the most important crops in Germany will be examined to utilize the high temporal resolution of the data. The new data source offers opportunities to improve crop classification as well as monitoring different phenological stages of the crops.