From June 1 to September 1, 2007 Delft University of Technology is participating in a major international experiment in Germany’s Black Forest, to learn more about what causes rain. Aircraft and an airship are to be used alongside ground-based observatories. Satellites will be used to gather the large-scale information.
The creation of rain is the result of a variety of physical processes. These processes influence each other and play out both at an extremely small scale (several micrometres) and on a very large one (100 kilometres). The spatial scale of weather models is a few kilometres, and physical processes which occur at a smaller scale have to be approximated. Cloud formation is an example of this. The complexity and differences in scale make weather modelling inaccurate in predicting the time and place of a downpour, and the quantity of rain which will ultimately fall.
The Black Forest has a lot of thunderstorms in summer, and the discrepancies between predictions and actual rainfall are enormous. This makes it an ideal natural ‘laboratory’. Spread over an area of 100 by 100 km, five temporary observatories are being set up with state-of-the-art remote sensing equipment to measure the atmosphere continuously. In July nine aircraft and an airship will also be deployed to carry out detailed measurements above, below and in the clouds. Satellites will be used to gather the large-scale data.
On June 4 TU Delft moved the TARA (Transportable Atmospheric RAdar) atmosphere radar to Germany. The instrument will be sited atop the Hornisgrinde (one of the highest peaks in the Black Forest). There it will measure the atmosphere together with other instruments (LIDARs [Light Detection And Ranging], radiometers, cloud radars). The TU Delft will also have access to two research aircraft (one French, the other German) which will fly through the clouds to measure their physical properties. These aircraft have been specially assigned to two Delft PhD candidates.
Within this international Convective and Orographically-induced Precipitation Study (COPS), TU Delft will be mainly concerned with the question as to how cloud and rain formation is influenced by dust particles in the atmosphere.
The influence of the aerosol-cloud interaction on the earth’s radiation balance is also one of the greatest unknowns in climate models. The data collected during COPS will be suitable for improving models describing the relationship between atmospheric dynamics and cloud formation.
Schedule-TARA will be transported to Germany on June 4;
-From August 1 TARA will be used in standard mode to build up a sufficiently statistically representative dataset routinely.
Roy Meijer | alfa
Conservationists are sounding the alarm: parrots much more threatened than assumed
15.09.2017 | Justus-Liebig-Universität Gießen
A new indicator for marine ecosystem changes: the diatom/dinoflagellate index
21.08.2017 | Leibniz-Institut für Ostseeforschung Warnemünde
Controlling electronic current is essential to modern electronics, as data and signals are transferred by streams of electrons which are controlled at high speed. Demands on transmission speeds are also increasing as technology develops. Scientists from the Chair of Laser Physics and the Chair of Applied Physics at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) have succeeded in switching on a current with a desired direction in graphene using a single laser pulse within a femtosecond ¬¬ – a femtosecond corresponds to the millionth part of a billionth of a second. This is more than a thousand times faster compared to the most efficient transistors today.
Graphene is up to the job
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...
19.09.2017 | Event News
12.09.2017 | Event News
06.09.2017 | Event News
26.09.2017 | Life Sciences
26.09.2017 | Physics and Astronomy
26.09.2017 | Information Technology