Identify and interpret fields and derived products
Jose Candido from WavEC talks in his presentation about the use of satellite derived altimetry data for wave energy applications.
Altimeter estimates of the significant wave height Hs are quite accurate. The assessment of the wave energy resource in deep water locations requires not only the knowledge of Hs but also of the wave period, in particular the energy period Te. Several models have been proposed in order to derive the mean zero-crossing period from the altimeter backscatter coefficient with reasonable accuracy. The attempts to establish a relation between Tz and Te revealed significant constraints. As a consequence, the exclusive use of altimeter data may be suitable only for preliminary wave energy resource assessment purposes. Additionally, given their wide geographic availability, altimeter Hs estimates are typically applied in the validation of wave model data used in wave energy resource assessment studies.
Sergio Muacho from IPMA gives a presentation on Jason-2 altimetry data. He explains the measuring principle and applies the data to track an Atlantic wave storm.
This presentation reports on the use of significant wave height (SWH) altimetry product, derived from OSTM/Jason-2 data, during a recent wave storm in the Northeast region of the Atlantic Ocean at mid-April 2012. Altimetric measurements provide data for wave model assimilation and also support ocean forecasts. Sérgio Muacho will focus on remote-sensed observations that cover a period of one week, and track the wave storm over the Atlantic between south of Iceland and the Portuguese Continental West coast, and the Gulf of Biscay. This study provides a summary of this wave storm and highlights the importance of having altimetry data in ocean areas, where there is a lack of observations, especially in off-shore regions.
Nuno Moreira from IPMA guides you through the web sites mentioned in the presentations during the Polar Satellites Week.
In this session you will be taken on a website tour, visiting pages where polar satellite products referred during the whole EUMETRAIN Polar Satellite Week can be visualized. “Web-Visits” will naturally include EUMETSAT or NOAA pages and it will be an opportunity to make a wrap-up on the contents previously discussed...
Piet Stammes from KNMI talks about aerosol retrieval with GOME-2 instrument onboard MetOp satellites since 2006. Intercomparison with other instrument data and examples round up the presentation.
Aerosols are small liquid or solid particles in the atmosphere, like soil dust, sulphate and nitrate droplets, organic compounds, volcanic ash, etc.. Aerosols affect weather and climate by reflection and absorption of sunlight, by affecting cloud formation and precipitation, and by reducing visibility. Satellite detection of aerosols is often difficult because of the relatively weak reflectance of aerosols as compared to clouds and the background reflection of the underlying surface. Using UV-Visible spectrometers like OMI and GOME-2, UV absorbing aerosols like biomass burning smoke, volcanic ash and desert dust can be detected, even in cloudy cases and over land surfaces. In this presentation the current and future aerosol products from GOME-2 available from the O3MSAF will be introduced.
Nigel Atkinson from the UK MetOffice presents the AAPP package to process ATOVS and AVHRR data. Some processing and visualisation examples are given.
The ATOVS and AVHRR Pre-processing Package (AAPP) is a tool to process sounder and imager data from the NOAA, Metop and FengYun polar orbiting satellites. It was originally developed in the late 1990s to support processing of direct broadcast data from the NOAA-POES satellites, and has since been extended to accommodate Metop (including IASI) and more recently Suomi-NPP. The package is maintained by the EUMETSAT Satellite Application Facility for Numerical Weather Prediction (NWP SAF). An overview will be given of the capabilities of AAPP, including how it complements other processing packages such as IMAPP and CSPP. AAPP products include calibrated, re-mapped radiances (for NWP) and derived products such as cloud mask. Examples of the products and their uses will be shown.
NOAA satellite analyst Sheldon Kusselson shows the variety of water vapour products available from polar platforms. A practical example concludes his presentation.
Since 1992 operational NOAA satellite analysts and forecasters have used polar orbiting microwave products to complement and supplement geostationary satellite, observational and computer model data to further improve precipitation forecasts. My session will provide an overview of current SSMIS and NOAA/MetOp MHS and AMSU polar orbiting microwave products, like Total Precipitable Water (TPW) and Rain Rate (RR) and how they can be used to help enhance precipitation forecasts with an emphasis on the eastern North Atlantic Ocean into the European continent. From these different individual satellite sensors microwave TPW and RR products have come a new class of satellite product called “the blended or merged product” that will also be discussed, displayed and compared with EUMETSAT geostationary satellite imagery. A case study showing these blended/merged TPW and RR products for the February 2010 Madeira storm will also be shown.
Steve Ackerman gives an introduction on cloud detection methods used to segregate cloud free from cloud contaminated satellite pixel.
Early in the history of polar orbiting satellite, imaging instruments were included to detect and classify clouds. Steve Ackerman will begin with a brief historical look at these first observations. This presentation will discuss the types of algorithms developed and applied to visible and infrared observations from the NOAA series, the two NASA EOS and the EUMETSAT MetOp platforms. Steve Ackerman will discuss areas of strength and weakness in cloud detection from these platforms and will end by exploring some climate and regional applications of the cloud analyzes from some of these cloud images.
Stefania De Angelis shows in her presentation the different categories of Hydro-SAF precipitation products derived from polar orbiting satellite data.
Monitoring and measurement of precipitation from satellite is an important capability for many types of users, such as the Meteorological Services, Hydro-geological Services and the structures of civil protection. The consortium H-SAF, within EUMETSAT, has among its objectives to provide continuous operational products for instantaneous measurement of rainfall using data from microwave instruments, on-board polar satellites, in synergy with the infrared data of the geostationary satellite MSG. In addition to the production operation, the HSAF provides validation service on each product and carries out independent validation of the benefits of the novel H-SAF satellite-derived data on hydrological practical applications.
Adam Dybbroe presents Nowcasting SAF products developed for polar satellites. He gives an overview on existing and future products retrieved from MetOp and NPP satellite data.
The EUMETSAT SAF to support Nowcasting (NWCSAF) develops two software packages, one for Geostationary imagery and one for polar satellite imagery. Both packages retrieve Cloud and other parameters relevant for Nowcasting and short range forecasting. The Polar Platform System (PPS) software package retrieves information on clouds and precipitation. The parameters/products derived are, Cloud Mask, Cloud Type, Cloud Top Temperature and Height, Precipitating Clouds, and a number of cloud microphysical parameters (e.g. liquid water path and cloud phase). The first version of PPS was released in 2004, and it was originally developed to run on local direct readout data from NOAA and Metop (AVHRR and AMSU/MHS). But recently it has been extended to run also on NPP/VIIRS data. And PPS is now also capable of running on many different data formats and services. It is currently being introduced on the EARS Network to run on NOAA19 and Metop-A. In this presentation Adam Dybbroe will give an overview of how PPS works, but the main focus will be on the parameters and products that can be derived with PPS, and how they can be used in Nowcasting applications.
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.