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METOP GOME-2 - Formaldehyde (HCHO) - Global

The Global Ozone Monitoring Experiment-2 (GOME-2) instrument continues the long-term monitoring of atmospheric trace gas constituents started with GOME / ERS-2 and SCIAMACHY / Envisat. Currently, there are three GOME-2 instruments operating on board EUMETSAT's Meteorological Operational satellites MetOp-A, -B, and -C, launched in October 2006, September 2012, and November 2018, respectively. GOME-2 can measure a range of atmospheric trace constituents, with the emphasis on global ozone distributions. Furthermore, cloud properties and intensities of ultraviolet radiation are retrieved. These data are crucial for monitoring the atmospheric composition and the detection of pollutants. DLR generates operational GOME-2 / MetOp level 2 products in the framework of EUMETSAT's Satellite Application Facility on Atmospheric Chemistry Monitoring (AC-SAF). GOME-2 near-real-time products are available already two hours after sensing. The operational HCHO total column products are generated using the algorithm GDP (GOME Data Processor) version 4.x integrated into the UPAS (Universal Processor for UV / VIS Atmospheric Spectrometers) processor for generating level 2 trace gas and cloud products. For more details please refer to relevant peer-review papers listed on the GOME and GOME-2 documentation pages: https://atmos.eoc.dlr.de/app/docs/

METOP GOME-2 - Cloud Fraction (CF) - Global

The Global Ozone Monitoring Experiment-2 (GOME-2) instrument continues the long-term monitoring of atmospheric trace gas constituents started with GOME / ERS-2 and SCIAMACHY / Envisat. Currently, there are three GOME-2 instruments operating on board EUMETSAT's Meteorological Operational satellites MetOp-A, -B and -C, launched in October 2006, September 2012, and November 2018, respectively. GOME-2 can measure a range of atmospheric trace constituents, with the emphasis on global ozone distributions. Furthermore, cloud properties and intensities of ultraviolet radiation are retrieved. These data are crucial for monitoring the atmospheric composition and the detection of pollutants. DLR generates operational GOME-2 / MetOp level 2 products in the framework of EUMETSAT's Satellite Application Facility on Atmospheric Chemistry Monitoring (AC-SAF). GOME-2 near-real-time products are available already two hours after sensing. OCRA (Optical Cloud Recognition Algorithm) and ROCINN (Retrieval of Cloud Information using Neural Networks) are used for retrieving the following geophysical cloud properties from GOME and GOME-2 data: cloud fraction (cloud cover), cloud-top pressure (cloud-top height), and cloud optical thickness (cloud-top albedo). OCRA is an optical sensor cloud detection algorithm that uses the PMD devices on GOME / GOME-2 to deliver cloud fractions for GOME / GOME-2 scenes. For more details please refer to relevant peer-review papers listed on the GOME and GOME-2 documentation pages: https://atmos.eoc.dlr.de/app/docs/

Methoden der Radarfernerkundung zur Analyse anthropozoogener Muster der Landnutzung in periodisch überfluteten Gebieten des westafrikanischen Sahel

Radarfernerkundung auf Basis der SAR-Satellitendaten der ERS-Plattformen ermöglicht die Aufzeichnung von Boden- und Vegetationsparametern, die vor allem mit den Faktoren Rauhigkeit, Wassergehalt und Salinität korreliert sind. Landnutzung in semi-ariden Regionen Westafrikas wird durch Übernutzung der Böden, Versalzung von bewässertem Land und Dezimierung von Baum- und Strauchschichten der Vegetation geprägt. Geeignete Methoden der Analyse von multitemporalen SAR-Daten der satellitengestützten Radarfernerkundung sollen helfen, vor allem regressive Veränderungen der Landnutzung zu erkennen und zu untersuchen. Informationen zu Bodenbedeckung, horizontaler Struktur der Vegetation und Bodenqualität sollen nachhaltige Entwicklungskonzepte unterstützen.

Oberflächentemperaturen von Laubwäldern zur Analyse von Wasser- und Hitzestress

Schwerpunktprogramm (SPP) 1488: Planetary Magnetism (PlanetMag), Evolution of geomagnetic dipole moment and South Atlantic Anomaly

The geomagnetic field shields our habitat against solar wind and radiation from space. Due to the geometry of the field, the shielding in general is weakest at high latitudes. It is also anomalously weak in a region around the south Atlantic known as South Atlantic Anomaly (SAA), and the global dipole moment has been decreasing by nearly 10 percent since direct measurements of field intensity became possible in 1832. Due to our limited understanding of the geodynamo processes in Earths core, it is impossible to reliably predict the future evolution of both dipole moment and SAA over the coming decades. However, lack of magnetic field shielding as would be a consequence of further weakening of dipole moment and SAA region field intensity would cause increasing problems for modern technology, in particular satellites, which are vulnerable to radiation damage. A better understanding of the underlying processes is required to estimate the future development of magnetic field characteristics. The study of the past evolution of such characteristics based on historical, archeo- and paleomagnetic data, on time-scales of centuries to millennia, is essential to detect any recurrences and periodicities and provide new insights in dynamo processes in comparison to or in combination with numerical dynamo simulations. We propose to develop two new global spherical harmonic geomagnetic field models, spanning 1 and 10 kyrs, respectively, and designed in particular to study how long the uninterrupted decay of the dipole moment has been going on prior to 1832, and if the SAA is a recurring structure of the field.We will combine for the first time all available historical and archeomagnetic data, both directions and intensities, in a spherical harmonic model spanning the past 1000 years. Existing modelling methods will be adapted accordingly, and existing data bases will be complemented with newly published data. We will further acquire some new archeomagnetic data from the Cape Verde islands from historical times to better constrain the early evolution of the present-day SAA. In order to study the long-term field evolution and possible recurrences of similar weak field structures in this region, we will produce new paleomagnetic records from available marine sediment cores off the coasts of West Africa, Brazil and Chile. This region is weakly constrained in previous millennial scale models. Apart from our main aim to gain better insights into the previous evolution of dipole moment and SAA, the models will be used to study relations between dipole and non-dipole field contributions, hemispheric symmetries and large-scale flux patterns at the core-mantle boundary. These observational findings will provide new insights into geodynamo processes when compared with numerical dynamo simulation results.Moreover, the models can be used to estimate past geomagnetic shielding above Earths surface against solar wind and for nuclide production from galactic cosmic rays.

Forschungsgruppe (FOR) 2589: Zeitnahe Niederschlagsschätzung und -vorhersage; Near-Realtime Quantitative Precipitation Estimation and Prediction (RealPEP), sub project: Coordination Funds

High-quality near-real time Quantitative Precipitation Estimation (QPE) and its prediction for the next hours (Quantitative Precipitation Nowcasting, QPN) is of high importance for many applications in meteorology, hydrology, agriculture, construction, water and sewer system management. Especially for the prediction of floods in small to meso-scale catchments and of intense precipitation over cities timely, the value of high-resolution, and high-quality QPE/QPN cannot be overrated. Polarimetric weather radars provide the undisputed core information for QPE/QPN due to their area-covering and high-resolution observations, which allow estimating precipitation intensity, hydrometeor types, and wind. Despite extensive investments in such weather radars, QPE is still based primarily on rain gauge measurements since more than 100 years and no operational flood forecasting system actually dares to employ radar observations for QPE. RealPEP will advance QPE/QPN to a stage, that it verifiably outperforms rain gauge observations when employed for flood predictions in small to medium-sized catchments. To this goal state-of-the?art radar polarimetry will be sided with attenuation estimates from commercial microwave link networks for QPE improvement, and information on convection initiation and evolution from satellites and lightning counts from surface networks will be exploited to improve QPN. With increasing forecast horizons the predictive power of observation-based nowcasting quickly deteriorates and is outperformed by Numerical Weather Prediction (NWP) based on data assimilation, which fails, however, for the first hours due to the lead time required for model integration and spin-up. Thus, RealPEP will merge observation-based QPN with NWP towards seamless prediction in order to provide optimal forecasts from the time of observation to days ahead. Despite recent advances in simulating surface and sub-surface hydrology with distributed, physicsbased models, hydrologic components for operational flood prediction are still conceptual, need calibration, and are unable to objectively digest observational information on the state of the catchments. RealPEP will prove that in combination with advanced QPE/QPN physics-based hydrological models sided with assimilation of catchment state observations will outperform traditional flood forecasting in small to meso-scale catchments.

Forschergruppe (FOR) 1740: Ein neuer Ansatz für verbesserte Abschätzungen des atlantischen Frischwasserhaushalts und von Frischwassertransporten als Teil des globalen Wasserkreislaufs, The Atmospheric Side of the Freshwater Budget

The focus of this project is to analyse the observed surface freshwater fluxes through improved estimates of evaporation and precipitation and their individual error characteristics in the HOAPS climatology and its ground validation in climate-related hotspots of the Atlantic Ocean. To enable that in a consistent manner we propose to establish an error characterization of the HOAPS evaporation data by triple collocations with ship and buoy measurements and between individual satellites and to improve the error characterization of the HOAPS precipitation by analysing available shipboard disdrometer data using point to area statistics. After these improvements, an analysis of the spatio-temporal variability of the surface fresh water balance E-P over the Atlantic Ocean is planned, especially with respect to the Hadley circulation and the hotspot regions of interest to related WPs. Also the atmospheric water transport shall be analysed in order to find the source or target region of local fresh water imbalances. And finally, a consistent inter-comparison of the upcoming global ocean surface salinity fields from SMOS with freshwater fluxes from the HOAPS climatology is proposed.

Einsatzmoeglichkeiten von ERS-1-SAR-Daten fuer geowissenschaftliche Anwendungen im alpinen Gelaende

Von dem am 16. Juli 1991 erfolgreich gestarteten ersten europaeischen Erderkundungssatelliten ERS-1 werden wesentliche Beitraege zum besseren Verstaendnis der komplexen Vorgaenge und dynamischen Veraenderungen im Gesamtsystem Erde und somit Entscheidungsgrundlagen fuer Massnahmen zum Schutze unserer Umwelt erwartet. Hinsichtlich der Einsatz- und Auswertmoeglichkeiten der SAR-Daten ueber Landoberflaechen mit ausgepraegtem Relief (wie in der Schweiz) bestehen erst geringe Kenntnisse. Es bedarf hier umfangreicher Grundlagenforschung, um diese Daten bei der Loesung aktueller, unser Land betreffender Aufgaben sinnvoll einsetzen zu koennen.

BOREAL- Follow-on Studies of German National Climate Programme - Part Landsurface Climatology: Studies of the Energy Budget of Subpolar Ecosystems Using Satellite Data and GIS-Technique

These studies are continuing the work, which was carried out within a project of the German National Climate Research Programme of the German Ministry of Research and Technology (BMFT) - part Landsurface Climatology (1986-1990). In two research areas in a subpolar environment of Northern Sweden satellite data and meteorological models are used to study the energetic processes at the soil-vegetation-atmosphere-interface and to simulate with different scenarios the effect of a change of vegetation types (possible due to a global warming) on the energy budget. Another aspect is to use high-resolution satellite data for environmental monitoring of the subpolar birch forest. One location is near the Abisko Research Station of the Swedish Academy of Natural Sciences, the other is around the Tarfala Glaciological Research Station of the University of Stockholm.

Analyse und Nowcasting von konvektiven Systemen mit VERA

Die genaue Vorhersage von Gewittern ist sowohl für die Wissenschaft als auch für die Öffentlichkeit ein wichtiges Anliegen, da konvektive Ereignisse im Sommer zu den größten Naturgefahren in unseren Breiten gehören. Um die Entstehungsprozesse von Gewittern genauer zu verstehen, ist eine Untersuchung von Konvektion auf einer hoch auflösenden Skala nötig. Nur damit kann man den heutigen Anforderungen an die Vorhersage (in Bezug auf Zeit, Raum und Intensität) gerecht werden. Zu diesem Zweck wird im nächsten Jahr im Rahmen von zwei internationalen Projekten (COPS und MAP D-PHASE) im Süden von Deutschland eine groß angelegte Messkampagne durchgeführt. Das Hauptziel dieser Kampagne ist die Erstellung eines hochwertigen Datensatzes für die Untersuchung konvektiver Prozesse, von der Auslösung von Konvektion über die Wolken- und Niederschlagsbildung bis hin zur Untersuchung von Wolkenchemie und Hydrometeoren. Damit sollen meteorologische (und hydrologische) Vorhersagen für konvektive Ereignisse verbessert werden. Sowohl bei COPS (Convective and Orographically-induced Precipitation Study; Teil des Priority Program SSP 1167 der Deutschen Forschungsgemeinschaft) als auch bei MAP D-PHASE (Mesoscale Alpine Program Demonstration of Probabilistic Hydrological and Atmospheric Simulation of flood Events in the Alpine region, ein von der Welt-Meteorologischen Organisation gefördertes Projekt) ist das Institut für Meteorologie und Geophysik in der Planungsphase vertreten. Im Rahmen des vorgeschlagenen Projektes soll die Messkampagne durch den Einsatz eines eigenen Meso-Messnetzes und Personal unterstützt werden, womit ein wichtiger Beitrag zu dem einmaligen Datensatz, der durch den Einsatz verschiedenster Messsysteme (Bodenstationen, Dopplerradar, Lidar, Satelliten, Flugzeuge, Radiosonden, ...) zu Stande kommt, geleistet wird. Mit Hilfe der Daten aus der Feldkampagne soll im Zuge des Projektes das Analyseverfahren VERA, das im Rahmen von FWF-Projekten am Institut entwickelt worden ist, einerseits für das Nowcasting von Gewittern, andererseits zur genaueren Niederschlagsanalyse, weiterentwickelt werden. Für beide Entwicklungsschritte wird dem Fingerprint-Ansatz, mit dem Zusatzinformation für das Downscaling meteorologischer Felder in die VERA-Analyse implementiert werden kann, eine wichtige Rolle zukommen. Dieser Ansatz wird für 3 Dimensionen, mehrere Fingerprints und höhere Auflösungen (bis 1km Gitterdistanz) erweitert. Mittels des Datensatzes werden neue Fingerprints entwickelt, die dazu beitragen werden, die Analysegenauigkeit für den Niederschlag und die Vorhersagbarkeit von Gewittern in Echtzeit mit Routinedaten zu verbessern. Das fertig entwickelte Analyseverfahren soll dann in einem weiteren Schritt zur Echtzeit-Validierung von hoch auflösenden Wettermodellen verwendet werden, wobei ein neuer Ansatz des Vergleiches zum Tragen kommt. Auch dadurch wird ein Beitrag zur besseren Vorhersagbarkeit von Gewittern geleistet.

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