Identify and interpret atmospheric phenomena
Vesa Nietosvaara showcases how the MTG's FCI instrument will improve the quality of satellite data, especially for users in high latitudes.
The first Meteosat Third Generation (MTG-I) satellite with Flexible Combined Instrument (FCI) was launched at the end of 2022. It will be followed later in 2024 by MTG-S Satellite with Infrared Sounder onboard. MTG will carry novelty instruments – Infrared Sounder, Lightning Imager and Ultraviolet Visible Near-infrared (UVN) Spectrometer - in the GEO orbit. Meteosat Third Generation aims to secure continuity and to increase the capabilities of the Meteosat satellites in response to requirements of the future forecast/nowcast systems. Altogether, the new and enhanced capabilities will allow us to make a huge step in better monitoring of our environment, and allowing development of new applications.
Nataša Strelec-Mahović (EUMETSAT) shows and analyses several cases of water vapour structures in the atmosphere using satellite imagery.
Features occurring in the WV6.2μm images indicate the processes going on in the atmosphere, since these dark (dry) and white (moist) structures result from a combination of vertical motion, moisture advection and horizontal deformation within the mid and upper troposphere. Frequently, water vapour images reveal structures such as dark stripes, mountain wave signatures, or circular or spiral formations known as water vapour eyes, eddies or vortices. We will look at how these features can be used as tracers of three-dimensional atmospheric motions on the meso- and synoptic scale and how they relate to e.g. jet-streams, upper-level lows or turbulence.
Ivan Smiljanić (EUMETSAT) shows how the current MSG satellites can see low-level moisture and how does the moisture affect the weather.
High humidity in the air, close to the ground, could make you feel soggy in the summer but otherwise you won’t notice it. So why is it important to know all about it – is there a lot or very little moisture, where is it, what are dynamics of the moisture field? Well, moisture is really a key ingredient for many features in the atmosphere that can affect our daily lives to a high degree, from thunderstorm clouds to a fog or rime. In this session we will see how water vapour becomes a fuel for features in atmosphere to form, through a few real examples.
Ivan Smiljanić (EUMETSAT) presents water vapour channels that will become available with the launch of the third generation of Meteosat satellites.
Water vapour molecules, i.e. a water gas in the atmosphere, absorbs radiation in different parts of spectrum. With present geostationary satellite, MSG, this fact is mostly utilised in the spectral region around 6 or 7 microns, i.e. in the Infra-red region. With the next generation of geostationary satellite, MTG, it will be possible to observe the processes of WV absorption in the solar part of the spectrum, namely around 900 and 1300 nm. A bit different processes of absorption, but also scattering are happening around those wavelengths – we will take a look what is exactly happening there, and how to utilise these processes to detect different features in the atmosphere.
Norman Wildmann presents a wind measurement technique based on the use of UAS, a.k.a. drones.
Exchange and transport processes in the ABL are driven by turbulence on a wide range of scales. Their adequate parameterization in numerical models is essential. In heterogenous and complex terrain, the common simplification of turbulence to statistical models does not necessarily hold. Coherent structures such as convective cells, gusts, slope and valley flows, but also turbulence in cities or behind wind turbines are features which are not well represented in models. A reason for the lack of understanding is the challenge to adequately sample their spatio-temporal structure. Small unmanned aerial systems (UAS, a.k.a. drones) are increasingly used to measure meteorological quantities, including the three-dimensional wind vector in the ABL. In this talk, methods and results will be shown how UAS, either fixed-wing or rotary-wing, can be used to obtain in-situ measurements and thus help to understand complex flows.
Ab Maas talks about the challenges that wind presents in ballooning.
Although balloons were by far the first manned aircrafts in the sky their economic and military importance stayed marginal.
The main reason for that is the difficulty of steering a balloon. Balloons go with the wind flow and the only way to steer a balloon is to find different wind directions at different heights. Therefore, wind and wind forecasts are of utmost importance for sport- and commercial ballooning.
HansPeter Roesli illustrated the impact of wind on clouds by examples taken from satellite imagery.
Vertical and horizontal winds in a moist airmass may generate characteristic cloud patterns. Vice versa specific cloud patterns expose the wind fields behind the scene. The talk illustrates this interplay with imagery from data of operational sun-synchronous and geo-synchronous imaging satellites. It shows cases like gravity waves, undular bores, haboobs, ship tracks or stack plumes.
Valerie-Marie Kumer tals about the challenges of flying in complex terrain.
Flying in complex terrain is challenging as orographic induced turbulence can lead to unexpected loss of aircraft controls. In order to keep aircraft operations as long as possible actable and safe a skilled turbulence forecast is of vital importance. Since turbulence forecasts are highly dependent on model resolution and parameterization schemes, they do not always hit the scores. With the knowledge of general fluid dynamics and observations regions and onset of hazardous conditions can be specified. Let us explore what we can look at to improve our turbulence forecasting skill.
Tomas Pucik gives a presentation on the severe tornado that took place in southern Moravia in June 2021.
Violent (F4 - F5) tornadoes are extremely rare in Europe, which makes it almost impossible for local forecasters or surveyors to build experience with such events. This makes appropriate training for dealing with such events very important. After providing a brief overview of the climatology of tornadoes across Europe, we concentrate on violent tornadoes from three perspectives. The first perspective is typical damage associated with tornadoes of such strength, as documented from a field survey of the Moravian tornado. The second perspective is a contrast of precautions needed to take in such an event compared to the standard set of precautions mentioned in the standard severe wind warnings. The third perspective is an overview of contemporary procedures on forecasting and nowcasting such events compared to the environment and evolution of the 24th June case.
Kathrin Baumann-Stanzer discusses the pros and cons of wind measurements principles and gives a historical overview.
First efforts to observe the wind profile within the lowest kilometres above ground go back to the 1920s. The development of radio transmission led, among other things, to an upswing in the area of radiosondes and captive balloons. The invention of ground-based remote sensing made it possible to monitor continuously the wind profile without costly deployment of personnel. The advantages and disadvantages of measurement principles are discussed based on selected examples from measurement campaigns.
Friedrich Obleitner gives an overview presntation on instruments and techniques used for ground-based wind measurements.
The standard surface wind speed and direction measurements are based on different measurement principles: cup anemometers and vanes, hot wires, pitot tubes and sonic anemometers. Pros and cons of the different measuring methods regarding accuracy and applicability will be discussed as well as some practical aspects concerning setup, maintenance and post-processing. Beyond surface wind measurements, the talk will also touch on ground-based systems to measure vertical wind profiles.
David M. Schultz gives a presentation on the different conceptual models approaches concerning occlusion processes in frontal systems.
This talk presents new conceptual models in cyclone structures and evolutions. How does the large-scale flow in which the cyclone is embedded determine the type of frontal evolution that occurs? How does the air flow through cyclones, and what can this tell us about the possibility for damaging winds at the surface? This talk concludes with general principles for how forecasters can improve their skill through the use of conceptual models in operational forecasting.