Extreme heat, dry conditions and strong winds quickly spread the fire in the cities of Mykland and Froland in the southern county of Aust-Agder, dampening fire-fighters attempts to squelch the blaze. Before being brought under control by more than 150 fire-fighters, aided by 16 helicopters (and much hoped for rain), the fire is estimated to have destroyed around 3000 hectares.
To assess the full extent of the damage, Norway’s KSAT (the Kongsberg Satellite Services) compared Envisat acquisitions taken before and after the event.
"At KSAT, we were quite surprised by how easy it was to detect the affected area in the image and to learn how extensive the damages are," Nina Soleng said. "We sent the images to the County Director of Forestry (Fylkesskogmester) of Aust-Agder County."
The Envisat Advanced Synthetic Aperture Radar (ASAR) image to the right was produced by combining and comparing an acquisition taken before the fire (15 May) with one taken after the fire (19 June).
Major fires are visible from space – satellites detect not only the smoke billowing from major conflagrations but also the burn scars left in their wake. Even the fires themselves appear as 'hotspots' when the satellites’ sensors scan the Earth's surface in infrared wavelengths.
More than 50 million hectares of forest are burnt annually, and these fires have a significant impact on global atmospheric pollution, with biomass burning contributing to the global budgets of greenhouse gases, like carbon dioxide.
Satellites have proven to be vital tools for keeping track of fires and are able to keep forests under constant surveillance. ESA satellites have been surveying fires burning across the Earth’s surface for the last decade. Worldwide fire maps based on this data are now available to users online in near-real time through ESA's ATSR World Fire Atlas (WFA).
The WFA data are based on results from the Along Track Scanning Radiometer (ATSR) instrument onboard ESA’s ERS-2 satellite and the Advanced Along Track Scanning Radiometer (AATSR) onboard Envisat. These twin radiometer sensors work like thermometers in the sky, measuring thermal infrared radiation to take the temperature of Earth's land surfaces.
By combining satellite-derived information, such as surface temperatures, land and vegetation cover and vegetation water content, with meteorological forecasting data, such as air temperature, wind speed and rainfall, forests can be systematically monitored to assess fire risks and allow fire fighters to plan fast and efficient actions to extinguish flames.
Within the context of the Global Monitoring for Environment and Security (GMES) initiative, ESA and the European Commission (EC) have jointly demonstrated the ability of satellite-based observations to respond to the operational needs of fire fighting teams through projects such as RISK-EOS and PREVIEW.
Mariangela D'Acunto | alfa
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Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.
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Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.
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Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
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For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.
Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...
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