Weather
Land surface albedo quantifies the fraction of energy reflected by the surface of the Earth. As a corollary it then also determines the fraction of energy absorbed by the surface and transformed into heat or latent energy.
Land surface albedo quantifies the fraction of energy reflected by the surface of the Earth. As a corollary it then also determines the fraction of energy absorbed by the surface and transformed into heat or latent energy. Land surface albedo therefore is a key variable for characterising the energy balance in the coupled surface-atmosphere system and constitutes an indispensable input quantity for soil-vegetation-atmosphere transfer models. On the other hand, the down-welling surface short-wave radiation flux (DSSF) refers to the radiative energy in the wavelength interval [0.3 to 4.0 microns] reaching the Earth\'s surface per time and surface unit. It essentially depends on the solar zenith angle, on cloud coverage, and to a lesser extent on atmospheric absorption and surface albedo.
First presentation is devoted to an introduction of method retrievals for surface albedo and DSSF products that are implemented in framework of the LSA SAF in using MSG /SEVIRI observations. A second presentation will detail the validation exercise of these two LSA SAF operational products, which is based on inter-comparison with other satellite products, in situ measurements and outputs from NWP models.
Lecture on unusual cyclogenesis taking place in the Mediterranean basin on 7 and 8 November 2011.
This case study took place in Mediterranean basin from 7th to 8th November 2011, with some interesting weather phenomena occurred there. It is shown that the sequential cloudiness type bands were; not organized convective system in the first step, then Comma feature in the next step, deep convection and finally occlusion. Because of confusing weather features connected to it, this weather phenomenon can not be classified as Tropical Cyclone nor as Rapid Cyclogenesis. The case is treated only from a synoptic point of view, using Meteosat-9 satellite images and ECMWF numerical fields from ePort web site and other graphical elaborations with Metview.
This presentation gives various applications of LSA SAF radiation products that we can find in four production areas for MSG satellite.
This presentation gives various applications of LSA SAF radiation products that we can find in four production areas for MSG satellite; Europe, Northern Africa, Southern Africa and Southern America. Firstly, variability (both seasonal and spatial) that we can find in albedo fields are discussed together with signatures, or features you can look for in LST fields. Relations between LST and vegetations, which comes from the fact that vegetation is controlling temperature by means of evapotranspiration are also shown here. Another application of radiation product is diagnose of various models via land surface temperature. At the end of presentation there are some words about long-wave and shot wave surface radiation budget, which are strongly influenced by clouds at seasonal scale.
Presentation on the physical principles and algorithms underlying the retrieval of Land Surface Temperature (LST) and emissivity from satellite observations.
The first block of this session presents the physical principles and algorithms underlying the retrieval of Land Surface Temperature (LST) and emissivity from satellite observations. Both geostationary, GEO (MSG) and low-orbit, LEO (Metop) satellite advantages and disadvantages are discussed. Emphasis of the presentation is on the methodologies used by LSA SAF for deriving these LST and emissivity products. The presentation also gives focus on the assessment of the uncertainty associated to the retrievals and respective validation is given.
Second part of this presentation is dedicated to algorithms used in the estimation of one of the components of the surface radiation budget - Down-welling Surface Long-wave Fluxes, i.e. DSLF. This product is derived from MSG SEVIRI instrument within LSA SAF. Problematics of firs 100m atmosphere long-wave radiation is also well discussed. Presented are examples and validation results that put into evidence the strengths and caveats of this product. Current Status and further developments (CDOP2) will follow.
Powerpoint: Land Surface Temperature
Powerpoint: Surface Radiation Budget
Presentation during the event week on Snow in January 2010.
In the first part of session 5 Elena Saltikoff (FMI) will talk about diagnosis techniques of snow with radar data more from a theoretical point of view. This talk will include the relevant parameters of the radar equation (di-electricity and diameter), cross sections and reflectivity profiles with bright band and dBZ-gradients. It was also discussed, how different fallspeeds of drops and snowflakes affect the dBZ values. Some applications of polarimetric radar will be considered at the end of this talk.
During the second part of this session Wilfried Jacobs (DWD) will discuss practical examples for diagnosis of precipitation types from radar data and will relate this kind of data to other data categories like radiosoundings, NWP and observations.
Presentation during the event week on Snow in January 2010.
Steinar Eastwood will present the operational Sea Ice products from the Ocean and Sea Ice Satellite Application Facility, both scientific and technical. Ongoing activities to improve the current products and develop new will be discussed and some examples of how the products are used will be shown.
Presentation during the event week on Warning in October 2010.
Presentation by Tanja Renko (DHMZ) who describes the warning system that was active in Croatia before joining the Meteoalarm. Then the decision process in giving a warning for Meteoalarm and the local authorities will be described using an example of a real warning case.
Presentation during the event week on Warning in October 2010.
Presentation by Michael Staudinger talks about the EMMA project and the meteoalarm website that integrates all important severe weather information originating from the official National Public Weather Services across a large number of European countries. The warning information is presented consistently to ensure coherent interpretation as widely as possible throughout Europe.
Presentation during the event week on Warning in October 2010.
Rob Groenland will look into more detail in the July 14th case of 2010. He will describe the meteorological part on the synoptic- and mesoscale. Furthermore he pays attention to the decision making process that finally lead to the issuing of a regional weather alarm for parts of the Netherlands that evening. Not only beforehand it is important the follow the procedures carefully but also in the aftermath it is essential to collect all the feedback and communication that took place between the expert- and weatheralarmteam but also from customers, end users and general public. Finally he shows you the results of an extensive KNMI damage survey that took place in the area of the most severe damage.
Presentation during the event week on Warning in October 2010.
KNMI takes great interest in collaborative decision making within the process towards issuing severe weather warnings. Collaborative decision making will equalize individual peak reactions by forecasters, it will also decrease the stress often felt by shift meteorologists in the onset phase towards a severe weather event. For this reason KNMI has implemented several consulting procedures within its new warning system.
During the first part of this presentation Frank Kroonenberg will tell you about setting objective warning threshold, the warning colour assignment system and will give more details on the decision making process that leads to a warning for extreme weather or even a weather alarm the highest state of warnings in the Netherlands.
Presentation during the event week on Warning in October 2010.
Finnish warnings are issued on 24/7 routines via radio, television and www. Warnings are provided for general public, authorities and commercial clients. Warnings are issued for the next 24 hours in advance, but in future outlooks for some days in advance will be issued in near future. In weather situations where it is estimated that weather will be hazardous an extra forecaster monitors the situation and makes situation awareness reports for authorities. Also authority bulletins for general public are possible in severe weather situations.
Presentation during the event week on Warning in October 2010.
Rainfall warnings have not been issued in Finland until 2009. In the earlier years heavy rain forecasting was considered to be a too challenging task. However, growing demand for warnings together with some advancements in forecasts have changed this. Nowadays FMI provides warnings for the general public, authorities and commercial clients. In this presentation FMI's heavy rain warnings are presented and discussed.