In Iran, close to the city Mosul, there is the Mosul Dam holding back the river Tigris from flooding the city, while fueling it with hydroelectricity at the same time. Kilometers above, satellites are orbiting Earth. Several latitudes further north, in Tromsø, somebody doubts the integrity of the dam: “The structure moved by 5-10mm over a year.”
Author: Jahn Nitschke
Engineers, scientists and representatives from the satellite industry gathered on the 6th and 7th of December in Tromsø for the “Innovationsdagen” to share stories about achievements and innovations. “The event is an arena for the local satellite industry,” stresses Torbjørn Eltoft, physicist and member of the management of the Centre for Integrated Remote Sensing and Forecasting for Arctic Operations – in short Cirfa. Satellite industry followed scientific expertise on northern lights in Tromsø, even before the University was founded. Many satellites have polar orbits – meaning the satellite crosses both poles – which makes Tromsø a good place to communicate with them.
“Most important is the Copernicus Program,” explains Eltoft. The program is a large Earth observation program run by the European Commission (EC) and the European Space Agency (ESA). It comprises of several satellite missions, Sentinel 1-6, some of them already in orbit, some of them planned. Sentinel-1a was it, which detected unbelievably small movements in the Mosul Dam, supporting doubts about its integrity. What, if it breaks? A nice photo from bird’s eye perspective and the conclusion that several km3 of water moved by significantly more than 5-10mm per year into the city of Mosul seems not helpful at first glance. But thinking twice, this immense capacity provides tools for many interests.
One of them is monitoring the Arctic. “Currents, winds, waves, sea ice,” lists Eltoft, “and also Arctic oil spills”. Exact data will be of great scientific use. Receding Arctic ice will lead to increased ship traffic in the high north – dangerous ship traffic, because the sea is rough and unpredictable. However, maybe less unpredictable with satellite remote sensing. “If a ship gets for example stuck in sea ice, satellite imagery might help to find a way for rescue ships,” explains Eltoft. The detection of oil spills in the Arctic is more of a precaution, with possible exploitation of Arctic oil resources in mind.
Earth Observation obviously also holds information of military value, and even more interesting is that data collected by the program will be accessible with small hurdles. This is interesting regarding privacy issues, which is a huge topic and unsolved challenge for international laws. However, processing these amounts of data – it was talked about more than 10 Terabyte per day – is also not a small issue. So as long as your backyard does not provide more than a million people with power, such as the Mosul Dam, probably nobody wants to watch it.