Weather
Presentation of Winter-Storm Emma which severely affected Central Europe with heavy downbursts and thunderstorms.
On 1 March 2008, the powerful late winter cyclone Emma caused widespread damage and claimed 14 lives in Central Europe. Embedded in the synoptic-scale storm field, deep convection along the cold front played a significant role in further enhancing the wind gusts. This presentation aims to unfurl an outstanding case of a rapid cyclogenesis, to match the events at the earth's surface with the storm structures seen in satellite and radar data, and finally to track down possible mechanisms which may have contributed to paving the way for one of the strongest downbursts ever documented worldwide.
The presenter analyses the mesoscale synoptic situation of medicanes from the past decades. He focuses on similarities in NWP fields.
The Mediterranean area can be affected by particular cyclones characterized by an unusual life cycle. This life cycle can be divided into two distinct parts: in the initial part the subject has a warm core and an asymmetric structure, which are typical aspects of a tropical storm. In the second part, it evolves rather like a cyclone of middle latitudes, usually explained by the classical theories; its origin is either on the sea as on the desert. These entities generally include extreme events, such as intense convection, strong winds and coastal storm surges; consequently, they assume a significant importance in the diagnostic and forecasting. This lecture will explain the energy contributions and the thermodynamic processes involved in the entire evolution, also describing the various significant aspects making use of adapted diagnostic procedures.
Kristian Horvath from the Croatian Met-Service focuses in his presentation on the different types of cyclogenesis in the Mediterranean Bassin.
The classification of cyclones and their tracks in the Mediterranean will be presented, with a special attention on the lee cyclones and their tracks when moving farther from the initiation area. Furthermore, the atmospheric ingredients at play during lee cyclone formation and development will be reviewed, such as the crucial role of the upper-level dynamical factors, but also the near-surface lee-side thermal or potential vorticity (PV) anomalies and surface fluxes, including their interactions with the orography and mutual non-linear synergies. In addition, the use of “PV thinking” will be demonstrated for easier conceptual understanding of the formation mechanisms. The results of numerical studies show that the intensity and track of lee cyclones are very sensitive to the details of the upper-level trough, such as its exact position relative to the mountain, the intensity and existence of sub-synoptic vorticity cores, which may result in reducing the predictability of lee cyclones in the Mediterranean area.
The presenter is senior forecaster at the Norwegian Met-Institute in Tromso. He refers on the synoptic aspects of Polar Lows.
The forecasting of Polar Lows is one of the most challenging tasks in weather forecasting in the arctic. The lecture will give a demonstration of basic forecasting methodology at the Norwegian Meteorological Institute, and show some typical signatures of the polar low as seen from satellite IR/visible imagery, from ASCAT and from other observational data. A climatologic survey is also given by the presenter.
The invention of weather satellites has opened a new area in weather forecasting. This presentation will give you an introduction from the early starts to the future with the third generation of satellites.
The invention of weather satellites has opened a new area in weather forecasting. Satellite observations enable to continuously monitor the weather regimes on the whole globe. Therefore they provide a powerful tool in weather forecasting. The first lecture of the satellite course leads from the invention of weather satellites to technical inventions and the current operational satellites.
Geostationary satellites operate in a height of 36000 km and provide high temporal resolution. In contrast polar satellites are found closer to the surface and therefore offer higher spatial resolution. This presentation will teach you more on the different satellite orbits.
Satellite orbits depend on the flying height of the satellites. This height is definded by gravitational and centrifugal forces. Geostationary satellites operate in a height of 36000 km and provide high temporal resolution. In contrast polar satellites are found closer to the surface and therefore offer higher spatial resolution. The second lecture of the satellite course leads from the physical principals to benefits and limitations of selected satellite orbits.
Lecture by Marianne Koenig (EUMETSAT) on the phyiscal principles of radiative transfer and remote sensing.
Satellite instruments measure radiation at different wave lengths. To correctly assess the information provided by these measurements, it is essential to know about laws of radiation as well as special characteristics of atmospheric gases. This lecture leads from physical principles to applications such as IASI measurements.
Lecture by Andreas Wirth on data aquisition and data processing to obtain rich and useful satellite images.
For the correct assessment of satellite images, the processes involved in data processing should be known very well. Data processing and applied algorithms have essential impact on the satellite images, such as for example gamma correction. This lecture leads from single counts to radiances and brightness temperatures. Finally a well chosen selection of applications will be shown.
Satellite instruments measure at various wavelenghts. Since atmospheric gases reveal different proporties when being measured at different wavelengths, this information can be essential to filter information.
Satellite instruments measure at various wavelengths. Since atmospheric gases reveal different properties when being measured at different wavelengths, this information can be essential to filter information. This lecture guides you the basic characteristics of the various SEVIRI channels to their applications.
Geostationary satellites enable to closely monitor the weather development at selected locations. This is particularly important for nowcasting convection and high impact weather. This lecture leads from general advantages of geostationary satellites to specific applications.
Geostationary satellites enable to closely monitor the weather development at selected locations. This is particularly important for nowcasting convection and high impact weather. This lecture leads from general advantages of geostationary satellites to specific applications.
A low altitude polar orbit is widely used for monitoring the Earth because each day, as the Earth rotates below it, the entire surface is covered. Typically, a satellite in such an orbit moves in a near-circle about 800 km.
Polar orbiting satellites fly at relatively low altitudes of about 800 km above Earth. Therefore they can provide satellite images at high horizontal resolution. When only one polar satellite is employed, the same spot on Earth is visited only twice per day. Therefore more than one polar satellite with different equatorial crossing times is required in order to attain more frequent observations. This lecture introduces you with the different instruments onboard of MetOp A and gives insight into the application of the retrieved information.
The Global Instability Index (GII) product is one of the MSG meteorological products and describes the instability of the clear atmosphere by a number of airmass parameters.
The European geostationary Meteosat Second Generation satellite (MSG) offers a variety of channels to use for various purposes, including nowcasting of convection. A number of applications have also been developed to make use of these new capabilities for nowcasting, especially for the detection and prediction of severe weather. The MSG infrared channel selection makes it possible to assess the air stability in pre-convective, i.e. still cloud free, conditions. Instability indices are traditionally derived from radiosonde profiles. Such indices typically combine measures of the thermal and the moisture properties and often only use a small quantity of vertical profile parameters. MSG based temperature and moisture retrievals are used for the derivation of stability indices, which are a part of the MSG meteorological products derived centrally at EUMETSAT. Such indices are of highly empirical nature and are often only applicable to certain geographic regions, but they can assess the likelihood of convection within the next few hours. Numerous test cases and the more quantitative verification process that was initiated by the South African Weather Service show the generally good warning potential of the derived instability fields. The added capability of a continuous monitoring of the instability fields that is guaranteed by MSG’s 15 minute repeat cycle is most valuable, since it provides nowcasters with new information much more regularly than the twice-a-day soundings at only limited number of stations. The current EUMETSAT instability product is aimed at helping a forecaster to focus his attention to a certain region, which he can then monitor more closely with other means like satellite imagery and radar data over the next hours.