What is Silvisense?
Silvisense is a service that provides automated forest monitoring using satellite data. Whenever new satellite data is available for your area of interest, Silvisense will automatically download it, and process it to find any changes in the forest and provide this information to the user without a need for further interpretation. The forest monitoring results can be inspected and downloaded from this website as well as from our WMS server.
Which forest monitoring services does Silvisense provide?
Silvisense currently provides the forest clearcutting product, which displays all forest that disappears from your area of interest. In addition, the service shows the satellite images and the land-cover classification for the latest acquisition as well as the historic acquisitions.
How precise can you measure forest clearcutting?
The Silvisense service uses Sentinel-2 data from the ESA Copernicus program. These satellites have a resolution of 10 meters, which means that each pixels corresponds to 10x10 meters of land. Because there may be pixels of noise, shadow and co-registration inaccuracy, all areas that are smaller than 10 pixels are filtered out. This means that at the moment, the minimum area of detection is 0.1 hectare. We are continuously working to make this area smaller and increase the precision of our service.
The areas of clearcutting are determined with a specified level of certainty. If the certainty after a single acquisition is not sufficiently high (because of non-ideal acquisition conditions) then a second acquisition might bring it to the required certainty, which means the clearcut area will be shown after the second acquisition. This allows a trade-off between the timeliness and the confidence of the update.
How do I provide my area of interest?
The area of interest can be provided to us in any form. The most common shape file formats we work with are kml and the esri shape file. An unique name or id for each polygon in the shape file is used as ‘parcel id’ and it is possible to search for this ‘parcel id’ on the map.
The typical area of interest can be any size really, but they are usually less than 10.000 km2.
How far back in time does the service go?
The service can be configured for any period of time. Some monitoring services, such as Pine Wilt Disease detection are seasonal and a certain season start and end date. A service cannot start before the satellite data has started to become available. The earliest data is from the start of the Sentinel-2A acquisitions, which is the summer of 2015.
How often are measurements made?
The two Sentinel-2 satellites fly over your area of interest once every 5 days to make an acquisition. However, the image can be clouded and then the measurement of your area of interest is not possible because the satellite cannot look through clouds. It is also possible that your area of interest is partly cloudy and then only the parts of the image that are not clouded will be visible. The Sentinel-2 images might have be clouded the majority of the time, depending on region and the time of year.
The second Sentinel-2 satellite (Sentinel-2B) has been providing data since the summer of 2017. In the period before this, there was only one Sentinel-2 satellite and the interval of the acquisitions was once every 10 days.
How do I use the website, download the files, access the WMS?
For the use of the website please see our manual that is shown under the Settings menu after you have logged in.
Can I share additional information about my area of interest?
Yes, if you have records for your area of interest with for example tree types or ages, the service can be tailored to your use. Your data can be verified by satellite sources or it can be used to develop more intelligent services for you and your area of interest. We have a standard NDA for this and we have taken the appropriate security measure to keep confidential company data safe.
What if I have more questions?
Please contact us via firstname.lastname@example.org for questions or comments.