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  • 1
    Publication Date: 2020-12-29
    Description: This manuscript assess the current and expected future global drivers of Southern Ocean (SO) ecosystems. Atmospheric ozone depletion over the Antarctic since the 1970s, has been a key driver, resulting in springtime cooling of the stratosphere and intensification of the polar vortex, increasing the frequency of positive phases of the Southern Annular Mode (SAM). This increases warm air-flow over the East Pacific sector (Western Antarctic Peninsula) and cold air flow over the West Pacific sector. SAM as well as El Niño Southern Oscillation events also affect the Amundsen Sea Low leading to either positive or negative sea ice anomalies in the west and east Pacific sectors, respectively. This strengthening of westerly winds is also linked to shoaling of deep warmer water onto the continental shelves, particularly in the East Pacific and Atlantic sectors. Air and ocean warming has led to changes in the cryosphere, with glacial and ice sheet melting in both sectors, opening up new ice free areas to biological productivity, but increasing seafloor disturbance by icebergs. The increased melting is correlated with a salinity decrease particularly in the surface 100 m. Such processes could increase the availability of iron, which is currently limiting primary production over much of the SO. Increasing CO2 is one of the most important SO anthropogenic drivers and is likely to affect marine ecosystems in the coming decades. While levels of many pollutants are lower than elsewhere, persistent organic pollutants (POPs) and plastics have all been detected in the SO, with concentrations likely enhanced by migratory species. With increased marine traffic and weakening of ocean barriers the risk of the establishment of non-indigenous species is increased. The continued recovery of the ozone hole creates uncertainty over the reversal in sea ice trends, especially in the light of the abrupt transition from record high to record low Antarctic sea ice extent since spring 2016. The current rate of change in physical and anthropogenic drivers is certain to impact the Marine Ecosystem Assessment of the Southern Ocean (MEASO) region in the near future and will have a wide range of impacts across the marine ecosystem.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
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  • 2
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    Technische Universität Berlin
    Publication Date: 2021-03-08
    Description: Background: Agriculture is a large and dynamic sector, essential for the supply of the population and thus in a complex area of tension. The growing population and the resulting need for optimization, greater efficiency and intensification are in direct conflict with the demand for sustainability, environmental compatibility and, above all, mitigation of climate change and its consequences. Precision agriculture can make a decisive contribution to increasing efficiency in particular. Because through the targeted and demand-oriented application of fertilizers and pesticides, but also spatially variable sowing, resources can be used better and in the best case even increase yields. Above all, if fertilizers are applied in the way that the plants need and can absorb them, in contrast to uniform application across the entire field, a surplus that can be washed into the groundwater can be avoided. A basis is therefore needed on which this variable application of resources can be determined. In practice, maps of current condition in the form of zones in the field or on-the-go measurements from sensors on the tractor are often used here. However, for comprehensive planning and holistic cultivation of crop, current and past spatial information maps, such as zone maps, are necessary. Satellite data are a data basis for such zones, as they are available in various types, current and retrospective and cover large areas spatially. Objective: This work explores possibilities to derive this zoning from satellite data and developes different approaches. The interrelations between satellite data, geoinformation data and agricultural data such as yield will be investigated and combined. The focus of the method development is the applicability in practice and the associated requirements of the farmer. Data: For method development and analysis 179 RapidEye scenes, 512 Landsat scenes, 43 Sentinel-2 scenes and 21 Planetscope scenes were used. Furthermore, the soil map „Bodenschätzung“, which not only transmits the information about the respective soil type, but also a quantification of the fertility respectively the yield potential in the form of „Bodenzahl“ and „Ackerzahl“. Digital terrain models in different spatial resolutions were used as well as in-situ measurements of nutrients, electrical conductivity and phenology. Methods and Results: In this thesis two methods and a data analysis are presented. The first method uses only optical satellite data (RapidEye) and processes these automatically into five relative yield zones, which reflect the expected relative yield averaged over several years. The method independently selects the appropriate data sets for a prescribed field, using different thresholds resulting from the reflectance values of individual bands. The zones are then separated on the basis of quantile values using an synthetic, averaged raster of the near infrared bands. The method is validated with actual yield data using the characteristics of box plots. The yield zones generated can then be used as management zones in precision farming. The second method also generates relative yield zones, suitable for use as a management zone, using RapidEye satellite data as well as soil map and relief information. This data fusion for yield zone modeling is based on belief structures and uses the Transferable Belief Model. Thus, individual expert knowledge from practical agriculture can be integrated into the fusion process. The knowledge generated in the course of method development about the relationship between remote sensing and GIS data and the actual yield on the field will be extended and consolidated in a large-scale data analysis with a time series of 13 years and 755 satellite scenes. It shows that there is a strong correlation between satellite data and yield data (up to a correlation value of r = 0.75, some values even higher). However, this correlation depends strongly on the phenological timing of - in this case - cereals and canola. In addition, the spectral and spatial resolution, as well as the growing conditions and the soil available water. Conclusion: Satellite data are very well suited for agricultural applications and for the derivation of management zones for precision crop cultivation. However, a lot of expert knowledge has to be applied in the selection of the appropriate remote sensing data as well as in the processing and methodology. The scientific and practical use of remote sensing data should be adapted to the specific problem and external conditions.
    Description: Hintergrund: Die Landwirtschaft ist ein großer und dynamischer Sektor, essentiell für die Versorgung der Bevölkerung und dadurch in einem komplexen Spannungsfeld. Die steigende Bevölkerung und der dadurch bestehende Bedarf an Optimierung, mehr Effizienz und Intensivierung steht im direkten Konflikt mit dem Anspruch nach Nachhaltigkeit, Umweltverträglichkeit aber vor allem der Eindämmung des Klimawandels und seiner Folgen. Gerade bei Fragen der Effizienzsteigerung kann der Bereich der Präzisionslandwirtschaft einen entscheidenden Beitrag leisten. Denn durch die gezielte und bedarfsorientierte Anwendung von Dünger und Pflanzenschutzmitteln, aber auch die gezielte und räumlich variable angepasste Aussaat, können Ressource besser genutzt werden und im besten Falle den Ertrag sogar steigern. Vor allem wenn Düngemittel so ausgebracht werden, wie die Pflanzen ihn benötigen und aufnehmen können, im Gegensatz zu einer uniformen Ausbringung über das ganze Feld hinweg, kann ein Überschuss, welcher in das Grundwasser ausgewaschen werden kann, vermieden werden. Es braucht also eine Grundlage, auf welcher diese variable Ausbringung von Ressourcen bestimmt wird. Hier werden in der Praxis oft Zustandskarten in Form von Zonen im Feld verwendet oder „on-the-go“-Messungen von Sensoren auf dem Traktor. Für die umfassende Planung und eine holistische Bearbeitung der Bestände sind aber aktuelle und zurückliegende, wie zusammenfassende Zustandskarten, beziehungsweise Zonenkarten nötig. Eine Datengrundlage für solche Zonen sind Satellitendaten, da sie in verschiedenster Art, aktuell und retroperspektiv vorliegen und große Flächen räumlich erfassen. Ziel: Diese Arbeit erforscht Möglichkeiten aus Satellitendaten eben diese Zonierung abzuleiten und sucht dabei verschiedene Herangehensweisen. Es sollen die Zusammenhänge zwischen Satellitendaten, Daten der Geoinformation und landwirtschaftlicher Daten wie Ertrag untersucht und miteinander kombiniert werden. Im Fokus der Methodenentwicklung steht die Anwendbarkeit in der Praxis und die somit einhergehenden Anforderungen des Landwirtes. Daten: Für die Methodenentwicklung und die Analyse wurden 179 RapidEye Szenen, 512 Landsat-Szenen, 43 Sentinel-2 Szenen und 21 Planetscope-Szenen verwendet. Weiterhin die Bodenkarte Bodenschätzung, welche nicht nur die Informationen über die jeweilige Bodenart übermittelt, aber auch eine Quantifizierung der Fruchtbarkeit beziehungsweise des Ertragspotentials in Form von „Bodenzahl“ und „Ackerzahl“. Digitale Geländemodell in unterschiedlichen räumlichen Auflösungen wurden verwendet, ebenso wie in-situ-Messungen von Nährstoffen, elektrischer Leitfähigkeit und Phänologie. Methoden und Ergebnisse: In dieser Doktorarbeit werden zwei Methoden und eine Datenanalyse vorgestellt. Die erste Methode verwendet einzig optische Satellitendaten (RapidEye) und verarbeitet diese automatisiert zu fünf relativen Ertragszonen, welche den zu erwartenden relativen Ertrag gemittelt über mehrere Jahre spiegelt. Die Methode wählt dabei eigenständig die passenden Datensätze für ein vorgeschriebenes Feld aus, unter Verwendung verschiedener Schwellwerte, die sich aus den Rückstrahlwerten einzelner Bänder ergeben. Auf Basis eines gemittelten Rasters der Bänder des nahen Infrarots werden dann auf Basis von Quartilswerten die Zonen separiert. Die Methode wird mit tatsächlichen Ertragsdaten mithilfe der Charakteristika von Boxplots validiert Die erzeugten Ertragszonen können dann als Bearbeitungszonen in der Präzisionslandwirtschaft verwendet werden. Die zweite Methode erzeugt ebenfalls relative Ertragszonen, geeignet für die Verwendung als Management Zone, verwendet neben RapidEye Satellitendaten auch die Informationen der Bodenkarte und des Reliefs. Diese Datenfusion zur Modellierung von Ertragszonen basiert auf Überzeugungsstrukturen und verwendet das Transferable Belief Model. Somit kann individuelles Expertenwissen aus der praktischen Landwirtschaft in den Fusionsprozess integrieren werden. Die Erkenntnisse, die im Laufe der Methodenentwicklung über die Zusammenhänge von Fernerkundungs- und GIS Daten und dem tatsächlichen Ertrag auf dem Feld generiert wurden, werden in einer großangelegten Datenanalyse mit einer Zeitreihe von 13 Jahren und 755 Satellitenszenen erweitert und gefestigt. Sie zeigt, dass es einen starken Zusammenhang zwischen Satellitendaten und Ertragsdaten gibt (bis zu einem Korrelationswert von r = 0.75, einzelne Werte höher). Diese Korrelation hängt aber stark ab vom phänologischen Zeitpunkt von – in diesem Falle – Getreide und Raps. Außerdem von der spektralen und räumlichen Auflösung, sowie den Wachstumsbedingungen und dem bodenverfügbaren Wasser. Fazit: Satellitendaten eignen sich sehr gut für die Anwendung in der Landwirtschaft und für die Ableitung von Bearbeitungszonen für den Präzisionspflanzenbau. Allerdings muss in der Auswahl der passenden Fernerkundungsdaten und auch der Verarbeitung und Methodik viel Expertenwissen angewandt werden. Die wissenschaftliche und praktische Verwendung von Fernerkundungsdaten sollte an die spezifische Fragestellung und die äußeren Bedingungen angepasst werden.
    Type: info:eu-repo/semantics/doctoralThesis
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  • 3
    Publication Date: 2020-09-23
    Description: Tourism in Antarctica is increasing, with visitors mostly choosing ship cruises often advertised as “Last chance tourism” taking advantage of increasing climate change awareness. While the existing guidelines for tourist operators are designed to protect this fragile region, many aspects of the local fauna, such as animal distribution and behavior, are still largely unknown due to difficulties studying these species. Without supporting data, it is challenging to design effective measures that minimize negative impacts of cruise ships on the Antarctic environment. A potential negative impact is the anthropogenic underwater noise generated by the vessels visiting the areas. Marine mammals rely on sound for many purposes such as foraging, orientation and reproduction. Ship noise can therefore potentially affect critical life phases of these species. Here we present a case study investigating how vessel acoustic presence affects the vocal behavior and timing of acoustic presence of leopard seals (Hydrurga leptonyx, LS) and Ross seals (Ommatophoca rossii, RS). RS are one of the least studied Antarctic species. Both pinniped spe cies are known to mainly produce underwater sounds during the mating season, presumably to attract mating partners in pack-ice areas. The German research icebreaker Polarstern (PS) annually resupplies Neumayer Station III (NS) - the German Antarctic Research Facility. Its arrival at the pier where cargo is unloaded has been noted to coincide with the onset of pinniped vocal activity in this area. Here, we use passive acoustic data that were recorded close to the pier over a 5-year period to investigate and compare how seal vocal behavior and vocal activity relate to the timing of ship arrival, presence and departure. The seals’ behavior over the relatively short analysis period of 5 years was complex due to their natural calling variation within life phases (before, during and after mating season). Thus, interpretation was not always straightforward. The arrival timing of the PS had an effect on RS, which delayed their appearance in 2010 and 2011 coinciding with the anticipated arrival of the ice-breaker. However, once arrived, both species showed no avoidance behavior and calling times remained unchanged despite PS. LS and RS calling activity decreased significantly during PS presence, but tended to recover instantly post PS departure. It is therefore unlikely that the animals left the area completely and decrease in calling may instead be related to masking. However, further research is needed to further explore what caused the decrease in calling. Both LS and RS seemed to use higher frequency call types during PS presence. The seals’ arrival times are also affected by prevailing ice conditions and associated food distribution. LS arrival time differed within the 5 years, whereas the RS arrived slightly earlier each year. The marine soundscape planning approach was applied to explore how ship arrivals can be timed to minimize potential disturbances. Ship quietening techniques and reduced ship speeds can also contribute to reduced underwater noise levels. Lastly, stricter legislative measures are needed to regulate which regions during which periods can be used for tourism.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Thesis , notRev
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  • 4
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    Unknown
    North Pacific Marine Science Organization (PICES) | Sidney, British Columbia
    In:  http://aquaticcommons.org/id/eprint/26965 | 42 | 2020-01-28 18:35:57 | 26965 | North Pacific Marine Science Organization (PICES)
    Publication Date: 2021-11-23
    Description: Report of Opening Session. Report of Governing Council. Report of the Finance and Administration Committee. Reports of Science Board and Committees. Report of the Climate Change and Carrying Capacity Scientific Program. Reports of Expert Groups. Session Summaries. Participants. PICES Members. PICES Acronyms.
    Keywords: Oceanography
    Repository Name: AquaDocs
    Type: book , FALSE
    Format: application/pdf
    Format: application/pdf
    Format: 325
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  • 5
    Publication Date: 2021-06-19
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
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  • 6
    Publication Date: 2021-09-24
    Description: Publications Office of the European Union, Luxembourg
    Description: Published
    Description: 7SR AMBIENTE – Servizi e ricerca per la società
    Keywords: Disasters ; Risks ; Climate Change Adaptation ; Disaster RIsk Management
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: report
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  • 7
    Publication Date: 2021-12-17
    Type: info:eu-repo/semantics/article
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  • 8
    Publication Date: 2020-12-14
    Description: When defining indicators on the environment, the use of existing initiatives should be a priority rather than redefining indicators each time. From an Information, Communication and Technology perspective, data interoperability and standardization are critical to improve data access and exchange as promoted by the Group on Earth Observations. GEOEssential is following an end-user driven approach by defining Essential Variables (EVs), as an intermediate value between environmental policy indicators and their appropriate data sources. From international to local scales, environmental policies and indicators are increasingly percolating down from the global to the local agendas. The scientific business processes for the generation of EVs and related indicators can be formalized in workflows specifying the necessary logical steps. To this aim, GEOEssential is developing a Virtual Laboratory the main objective of which is to instantiate conceptual workflows, which are stored in a dedicated knowledge base, generating executable workflows. To interpret and present the relevant outputs/results carried out by the different thematic workflows considered in GEOEssential (i.e. biodiversity, ecosystems, extractives, night light, and food-water-energy nexus), a Dashboard is built as a visual front-end. This is a valuable instrument to track progresses towards environmental policies.
    Type: info:eu-repo/semantics/article
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  • 9
    Publication Date: 2020-08-14
    Description: Cabled coastal observatories are often seen as future-oriented marine technology that enables science to conduct observational and experimental studies under water year-round, independent of physical accessibility to the target area. Additionally, the availability of (unrestricted) electricity and an Internet connection under water allows the operation of complex experimental setups and sensor systems for longer periods of time, thus creating a kind of laboratory beneath the water. After successful operation for several decades in the terrestrial and atmospheric research field, remote controlled observatory technology finally also enables marine scientists to take advantage of the rapidly developing communication technology. The continuous operation of two cabled observatories in the southern North Sea and off the Svalbard coast since 2012 shows that even highly complex sensor systems, such as stereo-optical cameras, video plankton recorders or systems for measuring the marine carbonate system, can be successfully operated remotely year-round facilitating continuous scientific access to areas that are difficult to reach, such as the polar seas or the North Sea. Experience also shows, however, that the challenges of operating a cabled coastal observatory go far beyond the provision of electricity and network connection under water. In this manuscript, the essential developmental stages of the “COSYNA Shallow Water Underwater Node” system are presented, and the difficulties and solutions that have arisen in the course of operation since 2012 are addressed with regard to technical, organizational and scientific aspects.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev , info:eu-repo/semantics/article
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  • 10
    Publication Date: 2021-09-07
    Description: New Zealand has a large exclusive economic zone (EEZ) of which the area between the 30 and 50 m bathymetric zone offers the most prospects for shellfish production. Only 0.3% of this zone would be required to increase New Zealand’s shellfish production by 150,000 t. The Enabling Open Ocean Aquaculture Program, funded by the New Zealand Ministry of Business, Innovation and Employment, is a collaboration aiming to develop technologies that will enable the extension of aquaculture into New Zealand’s harsh and challenging open ocean conditions, and facilitate adaptation to the escalating effects of climate change in inner shore environments. New Zealand has started expanding aquaculture into exposed environments, allowing farm expansion to meet increasing demand for aquaculture products but also enabling ventures into new aquatic products. Expansion into offshore developments is in direct response to mounting stakeholder interaction in inshore coastal areas. This document presents a brief overview of the potential zones for open ocean aquaculture, the influence of climate change, and two potential shellfish operational systems that may facilitate the expansion of shellfish aquaculture onto New Zealand’s exposed ocean sites.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
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