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METOP GOME-2 - Cloud Optical Thickness (COT) - 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. ROCINN takes the OCRA cloud fraction as input and uses a neural network training scheme to invert GOME / GOME-2 reflectivities in and around the O2-A band. VLIDORT [Spurr (2006)] templates of reflectances based on full polarization scattering of light are used to train the neural network. ROCINN retrieves cloud-top pressure and cloud-top albedo. The cloud optical thickness is computed using libRadtran [Mayer and Kylling (2005)] radiative transfer simulations taking as input the cloud-top albedo retrieved with ROCINN. 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/

Continuous recordings of environmental parameters at station 13, Platengrund (2021-09 - 2024-09)

Additionally, at four shallow water stations (Booknis Eck, Buelk, Behrensdorf and Katharinenhof) temperature, salinity and dissolved oxygen are continuously logged at 2-3 m depth by self-contained data loggers. These are: (I) MiniDOT loggers (Precision Measurement Engineering; http://pme.com; ±10 µmol L-1 or ±5 % saturation) including copper antifouling option (copper plate and mesh) to measure dissolved oxygen concentration and (II) DST CT salinity & temperature loggers (Star-Oddi; http://star-oddi.com; ±1.5 mS cm-1) to record the conductivity. Both sensor types additionally record water temperature with an accuracy of ± 0.1 °C. The sampling interval was set to 30 minutes for all parameters. In context of the long-term monitoring project RegLocDiv (Regional-Local-Diversity) by M. Wahl (Franz, M. et al. 2019a), another seven stations were equipped with the same two types of sensors at 4-6 m depth to continuously record environmental parameters (again: temperature, salinity, dissolved oxygen) and included into this data set. These stations are at: Falshoeft, Booknis Eck, Schoenberg, Westermarkelsdorf, Staberhuk, Kellenhusen and Salzhaff (abandoned in 2023). Since 2021, in the context of implementing a reef monitoring to fulfil obligations by the EU Habitats Directive, step-by-step, eleven further stations were installed at reefs in the Schleswig-Holstein Baltic Sea. These are at: Platengrund (14 m depth) and Mittelgrund (8 m) (both since 2021), at Walkyriengrund (9 m), Brodtener Ufer (8 m), Außenschlei (11 m), Kalkgrund (8 m), Stollergrund (7.5 m) and Flueggesand (10 m) (all since 2022), as well as at Gabelsflach (10 m), Sagasbank (8.5 m) and Stabehuk (11.5 m) (all since 2023). Again, at all of these 11 stations, temperature, salinity and dissolved oxygen are continuously logged by self-contained data loggers: Conductivity (and temperature) is logged by HOBO® Salt Water Conductivity/Salinity Data Logger (Onset Computer Corporation, Bourne, MA, USA; https://www.onsetcomp.com) using the U2X protective housing to prevent fouling on the sensors. The same MiniDOT loggers (Precision Measurement Engineering) as at the above mentioned more shallow stations (including antifouling copper plate and mesh) are used to measure dissolved oxygen concentration. Dissolved oxygen concentration data measured by the MiniDOT loggers are corrected for a depth of 10 m (or 2,5 m on the shallow stations) using the software provided by the manufacturer. Additionally, a manual compensation for salinity was calculated (see details in Franz, M. et al. 2019b). Quality control was carried out by spike and gradient tests, following recommendations of SeaDataNet quality control procedures (see https://seadatanet.org/Standards/Data-Quality-Control). All data values were flagged according to applied quality checks using the following flags: 1 = Pass, 2 = Suspect, 3 = Fail, 4 = Visually suspect, 5 = Salinity compensation fail (further explanations can be found in Franz, M. et al. 2019b).

Messsystem zur feldskaligen Bestimmung der Gasdiffusivität im Boden

Böden spielen im globalen Kreislauf von Treibhausgasen eine wesentliche Rolle. Der Gasaustausch zwischen Boden und Atmosphäre ist dabei von zentraler Bedeutung, aber in seiner räumlichen und zeitlichen Dynamik noch nicht hinreichend verstanden. Für die Messung der Gaskonzentration und die Bestimmung der Diffusivität von Böden (Ds) existieren etliche, kleinskalige Labor- und Feldmethoden. Aufgrund der räumlichen Heterogenität und der zeitlichen Dynamik der Bodenstruktur ist es aber kaum möglich, die Ergebnisse auf den Feldmaßstab zu übertragen. Zentraler Gegenstand des Projektes ist die Entwicklung eines Systems zur Messung der Gasdiffusivität (PeDiM) in landwirtschaftlich genutzten Böden, das über lokale Heterogenitäten mittelt und Ds auf der Feldskala misst. Es wurde bereits gezeigt, dass Gaskonzentrationen in porösen Medien mittels schlauchförmiger, nichtporöser, gasselektiver Membranen gemessen werden können. Das zugrundeliegende Messprinzip beruht dabei auf der selektiven Diffusion einzelner Gaskomponenten der Bodenluft in eine Anordnung von Membranschläuchen, die in definierter Länge im Boden verlegt werden. Unser Projekt baut hierauf auf und ein in-situ Mess- und Monitoringsystem für Ds wird entwickelt. Folgende Schritte sind vorgesehen: i) Das neu entwickelte Messprinzip wird für die quasi-kontinuierliche Bestimmung von Ds für einen PeDiM-Prototypen im Labormaßstab umgesetzt. ii) Für einen präzisen Einbau des Messsystems im Feld wird ein Installationsgerät entwickelt, das Störungen des Bodens auf ein Minimum reduziert. iii) Der PeDiM-Prototyp wird in 2D- und 3D-Mesokosmen mit unterschiedlichen Substraten unter kontrollierten Bedingungen getestet. Parallele Ds-Messungen mit etablierten Messverfahren erlauben dabei die PeDiM-Konfiguration zu optimieren. vi) Optimierte PeDiM-Messysteme werden in einem Ackerboden eingebaut und Ds im Oberboden in einem mehrmonatigen Feldversuch gemessen. Die Ergebnisse werden im Zusammenhang mit wetterabhängigen Wassergehaltsänderungen und dynamischen Veränderungen der Bodenstruktur interpretiert. Der direkte Vergleich mit etablierten, kleinskaligen Labor- und Profilmessmethoden erlaubt Skaleneffekte experimentell zu untersuchen und nachzuweisen.Im Erfolgsfall steht ein innovatives, für die Langzeitbeobachtung ausgelegtes Mess- und Monitoringsystem zur Verfügung, das es zum ersten Mal erlaubt, quasi-kontinuierlich Ds im Feldmaßstab zu messen. Damit wird eine für Transportprozesse wesentliche Größe in Abhängigkeit atmosphärischer Randbedingungen auf einer Skala erfasst, die für die Interaktion von Boden und Atmosphäre relevant ist. Interessant für insbesondere landwirtschaftlich genutzte Böden ist dabei der völlig neue Zugang zur Beurteilung der zeitlichen Dynamik und Wechselwirkung zwischen Bodenstruktur und Ds. Ein kontinuierliches Monitoring von Ds erlaubt außerdem eine Kopplung von Treibhausgasemissionen mit Umsatzprozessen in Böden, was schließlich die Entwicklung von prognosefähigen Modellen unterstützt.

Spurengasflüsse und Stickstoffumsetzungen in stark verwitterten Böden unter Regenwaldtransformationssystemen

An allen 32 Standorten soll Folgendes durchgeführt werden: (a) bodenphysikalische und -chemische Analysen bis zu einer Tiefe von 2 m anhand einer Kombination aus falsche Zeitreihen- und longitudi-nalen Ansätzen; (b) Messungen mikrobiell gesteuerter Stickstoffumsetzungen im Boden und mikro-bieller Biomasse im Oberboden; (c) ganzjährige in-situ Messungen von NO, N2O, CH4 und CO2- Flüssen sowie Messungen der entsprechenden Einflussgrößen; (d) Entwicklung von Regressionsmo-dellen zwischen jährlichen Spurengasflüssen und einfach zu messenden Proxy- Variablen der Kont-rollgrößen im Boden; und (e) Messungen der Boden-CH4 und -CO2-Flüsse sowie in-situ Inkubationen von Epiphyten auf Ölpalmen.

Establishment of Teak plantations for high-value timber production in Ghana

Background and Objectives: The project area is located in the Ashanti Region of Ghana / West Africa in the transition zone of the moist semideciduous forest and tropical savannah zone. Main land use in this region is subsistence agriculture with large fallow areas. As an alternative land-use, forest plantations are under development by the Ghanaian wood processing company DuPaul Wood Treatment Ltd. Labourers from the surrounding villages are employed as permanent or casual plantation workers. Within three forest plantation projects of approximately 6,000 ha, DuPaul offers an area of 164 ha (referred to as Papasi Plantation) - which is mainly planted with Teak (Tectona grandis) - for research purposes. In return, the company expects consultations to improve the management for sustainable timber and pole production with exotic and native tree species. Results: In a first research approach, the Papasi Plantation was assessed in terms of vegetation classification, timber resources (in qualitative and quantitative terms) and soil and site conditions. A permanent sampling plot system was established to enable long-term monitoring of stand dynamics including observation of stand response to silvicultural treatments. Site conditions are ideally suited for Teak and some stands show exceptionally good growth performances. However, poor weed management and a lack of fire control and silvicultural management led to high mortality and poor growth performance of some stands, resulting in relative low overall growth averages. In a second step, a social baseline study was carried out in the surrounding villages and identified landowner conflicts between some villagers and DuPaul, which could be one reason for the fire damages. However, the study also revealed a general interest for collaboration in agroforestry on DuPaul land on both sides. Thirdly, a silvicultural management concept was elaborated and an improved integration of the rural population into DuPaul's forest plantation projects is already initiated. If landowner conflicts can be solved, the development of forest plantations can contribute significantly to the economic income of rural households while environmental benefits provide long-term opportunities for sustainable development of the region. Funding: GTZ supported PPP-Measure, Foundation

Natural Forest Management in Caracarai, Roraima, Brazil

Objectives: Sustainable management of tropical moist forests through private forest owners will become increasingly important. Media report that in Brazil, particularly in Amazonia, approx. 80 percent of the timber harvested is from illegal sources. Private management of forests according to internationally acknowledged standards offers an opportunity to significantly lower the portion of illegally cut timber. Moreover, it contributes significantly to the conservation of the Amazon forest. Private forest owners show a clear long-term commitment towards the implementation of management standards according that is ecologically compatible, socially acceptable and economically viable. The project area, a pristine forest in legal Amazonia in the transition zone between moist tropical forests and savannas (cerrado), is extremely diverse in floristic and faunistic terms. The institute cooperates with the private forest owner. Main tasks are to document the faunistic and floristic diversity, to calculate the Annual Allowable Cut and to elaborate concepts for site-specific silviculture. Results: To date (Oct. 2006) the following activities were started: - a comprehensive inventory system for planning at the FMU-level has been successfully introduced; - the inventory system for the annual coupe area has been designed and data for the first coupe are being processed; - the annual allowable cut is currently calculated based on the results of the above described inventories; - two fauna surveys are completed; one focusing on large mammals and one on the avi-fauna. A long-term monitoring concept to assess the influence of forest management on the faunistic diversity is currently under development; - forest zoning is completed applying terrestrial surveys and interpreting high-resolution satellite images; - a study on the use of Bethollethia excelsa-fruits (Brazil nuts) is currently implemented; - a study on timber properties of lesser known species is currently implemented.

METOP GOME-2 - Water Vapour (H2O) - 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 H2O 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. The total H2O column is retrieved from GOME solar backscattered measurements in the red wavelength region (614-683.2 nm), using the Differential Optical Absorption Spectroscopy (DOAS) method. 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 - Ozone (O3) - 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 ozone 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. The new improved DOAS-style (Differential Optical Absorption Spectroscopy) algorithm called GDOAS, was selected as the basis for GDP version 4.0 in the framework of an ESA ITT. GDP 4.x performs a DOAS fit for ozone slant column and effective temperature followed by an iterative AMF / VCD computation using a single wavelength. 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/

Vergangenheit trifft Zukunft − Historische Daten und Citizen Science erhöhen die Nachweisdichte des Feuersalamanders in der Sächsischen Schweiz

Für den Schutz des in Sachsen stark gefährdeten Feuersalamanders (Salamandra salamandra) ist − nicht zuletzt wegen zunehmender Gefährdung durch Klimawandel und Pathogene wie den Chytridpilz Batrachochytrium salamandrivorans (Bsal) − ein detailliertes Wissen zu dessen Verbreitung essenziell. Dabei sollten vorhandene Artnachweise aus allen verfügbaren rezenten und historischen Quellen herangezogen und für zielgerichtete Freilanderfassungen berücksichtigt werden. Zur Verdichtung der Fundpunkte von Feuersalamandern in Sachsen und speziell im Verbreitungsschwerpunkt Sächsische Schweiz wurden historische Nachweise revalidiert und mittels einer Citizen-Science-Kampagne durch aktuelle Nachweise ergänzt. So konnte die Anzahl der bislang in etablierten Artdatenbanken verfügbaren Nachweise erheblich gesteigert werden. Durch eine Synthese der multiplen rezenten und historischen Quellen kann somit erstmals die zeitliche Entwicklung der Vorkommen bis auf Gewässerebene nachvollzogen werden. Darauf basierend sind nunmehr ein gezieltes Langzeitmonitoring sowie eine prädiktive Analyse der Bestands- und Habitatentwicklung möglich.

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