EyeOnWater

Overpass notification

Want to make you observation count at a maximum? Switch on overpass notication!

When using the EyeOnWater app you observe the water and collect "in situ" (meaning "at the location") information about water colour, transparency and possibly other parameters when you use the App’s expert modus. This is important information that  informs local water management authorities  about the water-quality status exactly at the time and place when you visited the location. Now you have the option to do a measurement exactly at the time when a satellite is overhead and makes an observation. You will be in that image and your observation is synchronized with the satellite observation of the whole water system.  

Water management authorities nowadays  use remote sensing, meaning observations collected via satellites that hold sensors capable of measuring signals that represent water colour, sea surface temperature, currents,and so on. But these signals need ground truthing to validate them against the actual value, measured "in situ". In such a case it is very important that the in-situ measurement is done at or near the same time when the satellite overpasses.   

Co-location image // colocation.jpg (105 K)Instruments like Landsat-8 or -9 or Sentinel 2A and B revisit every spot on Earth every 10 to 15 days. We know from all of these instruments when they will take an observation of your home location and can provide you the exact timing in days, hours, minutes and even down to the second. To get this information, switch on the overpass notification option. The EyeOnWater overpass notification provides assistance, and when activated you will receive a notification 24 hrs in advance when you could best go out in the field to observe around the "home location" you have entered.

Remote sensing does not provide a good image when there are clouds, which means that there are gaps in observation that need to be filled. Authorities have regular monitoring in place, but not in every water body or every location. Your data will help to fill these gaps.  

We welcome your feedback on use of this option in practice.