The Department of Physical Sciences at the University of Helsinki has acquired a state-of-the-art polarimetric weather radar. The new radar is reserved exclusively for research. Its most important meteorological research target is the physics of rain clouds, and scientists intend to focus on snow and sleet in particular. Snowfall and its polarimetric measurements have hardly been studied anywhere else in the world, although in the Finnish conditions, for instance, snowfall is one of the key weather elements.
The first test measurements of the prototype radar built for the University’s radar laboratory provided good evidence for the potential of a polarisation weather radar. The largest road traffic catastrophe in the Helsinki metropolitan area took place on 17 March 2005, with several multiple pile-ups on all Helsinki. The new radar was just undergoing test runs and it immediately revealed the meteorological factors which led to the accidents.
Radar images showed that the road conditions before the accident were dry and cold with only slight snowfall. There was, however, supercooled water in the air, which made the road surfaces slippery immediately prior to the accidents. At the time of the accidents, a narrow zone of heavy snowfall arrived from the south, suddenly reducing visibility. In places, this was followed by a larger area of snowfall with a high content of supercooled water.
Minna Meriläinen | alfa
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At the productronica trade fair in Munich this November, the Fraunhofer Institute for Laser Technology ILT will be presenting Laser-Based Tape-Automated Bonding, LaserTAB for short. The experts from Aachen will be demonstrating how new battery cells and power electronics can be micro-welded more efficiently and precisely than ever before thanks to new optics and robot support.
Fraunhofer ILT from Aachen relies on a clever combination of robotics and a laser scanner with new optics as well as process monitoring, which it has developed...
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.
A warming planet
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.
The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...
Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...
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!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
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