You can not see it. But it sees us. The satellite that monitors Lake Mjøsa and takes pictures of the lake every day. Professor at NTNU in Gjøvik, Jon Yngve Hardeberg studies the first image they have received with great curiosity. Each pixel in the image contains lots of information, he explains. – What we hope to achieve is to be able to recognize the signature of the algae if they come. If something happens we will look at the data behind that oi; here something is happening. PHOTOS: The researchers at NTNU are studying the first satellite images of Lake Mjøsa. Photo: Lars Erik Skrefsrud Rain + heat = danger It is important to follow the situation in Norway’s largest lake. In recent years, there have been several major blooms of blue-green algae, ie cyanobacteria. These can be toxic and make people sick. Last year there was so much that several of the municipalities around Lake Mjøsa had to ban swimming. Now the researchers are excited. After heavy rainfall and subsequent hot weather, there may be danger on the move again. – Yes, it fits with the hypothesis we have had that such weather will be favorable for these cyanobacteria, so we are a little excited if we get a boom now, says Jan-Erik Thrane in the Norwegian Institute for Water Research. Wenche Engeskaug and the kids she has with her on the beach in Brumunddal enjoy themselves in the water and remember with horror how the blue-green algae ruined the joy of swimming last year. BATHING JOY: Wenche Engeskaug and the kids in the family love to swim and hope there are no algae / bacteria this year. Photo: Knut Røsrud – It was not nice to go out into the water. There was a green film all over the water’s edge. I was skeptical then, says Engeskaug. She is happy with the surveillance and thinks it gives people a better opportunity to take their precautions. These are blue-green algae / blue-green bacteria Blue-green bacteria, also called cyanobacteria (and blue-green algae), are a type of bacteria that are found naturally in soil, air and water. They are found in salt water, fresh water and brackish water. There are over 2000 different species. Blue-green bacteria have chlorophyll and drive photosynthesis. In Norway, we can see large accumulations of blue-green bacteria at sea in the summer when they bloom and lie like large green flakes on the surface. This is called water flower. Since the blue-green bacteria have chlorophyll and carry out photosynthesis, it was previously thought that they belonged to the algae, and they were therefore called blue-green algae. The blue-green bacteria have many roles in nature. Common to them is that they have chlorophyll and convert light energy into chemical energy by photosynthesis at the same time as they secrete oxygen, O2. Blue-green bacteria can bind nitrogen, and they therefore play an important role in the nitrogen cycle on earth. Some blue-green bacteria produce toxins that act on animals and humans and can do great damage, for example during a flowering. Other species produce substances that give off the smell and color of the water. The fewest blue-green bacteria are suitable for human consumption. An exception is Spirulina which is grown industrially and is used as a dietary supplement because it is rich in proteins, vitamin B 12 and minerals. It also contains antioxidants and is also used to color food. Source: Store Norske Leksikon Early warning The goal is precisely to be able to detect the bacteria before they reach the shoreline and people become ill or have allergic reactions. The satellite will hover around and take pictures of Lake Mjøsa two or three times a day. This satellite monitors MjøsaNTNU While traditional water monitoring often involves taking random samples in some places, the satellite will give them images of the entire lake. – Now we have a contingency and are ready to go out and take extra samples of both water quality and these algae, says researcher and project manager at NIVA, Jan-Erik Thrane. Then they can initiate measures and notify municipalities, the population and others affected at an early stage. World-class technology “Mission Mjøsa” consists of several projects and many partners. The satellite monitoring of the algae situation is in the start-up phase and it is NIVA and the technology experts at NTNU in Trondheim and Gjøvik who work together. SATELLITE: This satellite that NTNU in Trondheim has built now takes several pictures of the whole of Lake Mjøsa every day. Photo: Illustration: NTNU The satellite is NTNU technology from A to Z, and it can be controlled to retrieve data exactly where they want to see. – We look at algae using satellite. As far as we know, this is the first time this has been done in Norway, says Professor Jørn Wroldsen. The images that are collected will be analyzed by experts at NTNU in Gjøvik. – The color laboratory at Gjøvik has gained international expertise in analyzing hyperspectral images, so those involved in this at Gjøvik are the best in the country, perhaps in the world, at doing such things, says Wroldsen. Now the researchers are hoping for a lot of nice weather. If it is cloudy, they will not be able to see anything in the pictures. Jan-Erik Thrane in NIVA thinks the collaboration is exciting and important for the future. – I have hopes that the project will contribute to developing the methodology for monitoring Lake Mjøsa in the future. He hopes it will strengthen the data base on a larger scale and provide an overview of the entire lake.
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NTNU monitors algal blooms in Lake Mjøsa with satellite – news Innlandet – Local news, TV and radio
