Küstenforschung


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Trailer: Die Wirbeljagd

Hier ist der Vorgeschmack auf den neuen 360° Film „Die Wirbeljagd“. Der Film selbst hat am 13. Juli 2017 Premiere im Planetarium Hamburg und wird ab August dort regelmäßig zu sehen sein. Weitere Informationen gibt es auf der Website Uhrwerk Ozean.

Trailer: Die Wirbeljagd

 

Auf dem youtube Kanal des HZG sind noch weitere tolle Clips zu sehen:

360° Wissenschaft – Trailer „Die Wirbeljagd -Expedition Uhrwerk Ozean“

360° Wissenschaft – Die Expedition

360° Wissenschaft – Die Küste


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Erfolgreiche Teilnahme an der ICCE

Vom 18.06. – 22.06.2017 fand die 16th International Conference on Chemistry and the Environment (ICCE) am Campus Blindern der Universität Oslo statt. Aus der Abteilung Umweltchemie präsentierten Zhiyong Xie, Jonathan Fengler und Christina Apel ihre Forschungsarbeiten.

Zhiyong Xie hielt einen Vortrag zu “Long-range Transport and Spartial Distribution of Organophosphate Flame Retardants and plastizicers in the Marine and Polar Environment”. Jonathan Fengler, der seit Ende letzten Jahres seine Masterarbeit zum Thema „Entwicklung einer Methode zur Bestimmung von synthetischen Antioxidantien in der marinen Umwelt“ durchführt, nutzte den internationalen Rahmen, um seine bisherigen Ergebnisse vorzustellen und zu diskutieren.

Christina Apel präsentierte ihre Forschungsarbeit zu „Occurrence and distribution of organic UV stabilizers in sediments of the Bohai Sea and Laizhou Bay“ in einem Poster-Beitrag, welcher mit dem Best Poster Award 2017 der EuCheMS Division of Chemistry and the Environment ausgezeichnet wurde.

Herzlichen Glückwunsch zum Best Poster Award, liebe Christina!

Foto: Ulla Bollmann


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Publications

Johannes Pätsch, Hans Burchard, Christian Dieterich, Ulf Gräwe, Matthias Gröger, Moritz Mathis, Hartmut Kapitza, Manfred Bersch, Andreas Moll, Thomas Pohlmann, Jian Su, Ha T.M. Ho-Hagemann, Achim Schulz, Alberto Elizalde, Carsten Eden (2017): An evaluation of the North Sea circulation in global and regional models relevant for ecosystem simulations. Ocean Modelling (2017), doi:10.1016/j.ocemod.2017.06.005

Abstract:

Simulations of the North Sea circulation by the global ocean model MPI-OM and the regional ocean models GETM, HAMSOM, NEMO, TRIM are compared against each other and with observational data for the period 1998-2009. The aim of the study is to evaluate the quality of the simulations in particular with respect to their suitability to drive biogeochemical shelf sea models. Our results demonstrate the benefit of the global model to avoid the specification of lateral open boundary conditions. Due to its stretched grid configuration, which provides a higher grid resolution at the Northwest European Shelf, the global model is able to reproduce the large-scale features, such as the water mass distribution and the thermal stratification in the central and northern North Sea, qualitatively similar to the regional models. The simulation of temperature and salinity near the coast however, shows large biases in almost all models because of the coarse meteorological forcing and too coarse vertical resolutions. The simulation of the Baltic Sea exchange and the spread of freshwater along the Norwegian coast proved difficult for all models except GETM, which reproduces impacts of the Baltic Sea outflow reasonably well.

 

Florian Dutschke, Johanna Irrgeher and Daniel Pröfrock (2017): Optimisation of an extraction/leaching procedure for the characterisation and quantification of titanium dioxide (TiO2) nanoparticles in aquatic environments using SdFFF-ICP-MS and SEM-EDX analyses. Analytical Methods, doi:10.1039/C7AY00635G

Abstract:

The quantitative recovery of nanoparticles from environmental samples represents a critical step during the implementation of routine analytical monitoring methods for the reliable quantitative determination of nanomaterials released into aquatic environments at the expected low concentration levels. In this work, several approaches based on different extraction agents have been evaluated with respect to their suitability for the recovery of TiO2 nanomaterials from fresh sediment samples. Centrifugal-field-flow-fractionation (SdFFF) hyphenated to inductively coupled plasma tandem mass spectrometry (ICP-MS/MS) has been applied to separate the extracted nanoparticles as well as to overcome the known interference problem related to their Ti-specific detection when using ICP-based techniques. SdFFF-ICP-MS/MS method validation included in particular parameters such as particle recovery or stability of the particle size-distribution. Spike recoveries from the optimized colloidal extraction procedure of up to 95 ± 11% have been achieved. In a case study conducted from 2015 to 2016, the developed method was applied to monitor the release of nano-sized TiO2 materials into a lake environment that is frequently used for recreational activities such as swimming and surfing. The investigated sediment samples show a significant increase of the Ti concentration from 26.2 ± 2.7 mg kg−1 in June 2015 to 40.2 ± 4.6 mg kg−1 in December 2016 originating from TiO2 particles.


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Das Freitagsfoto

Foto: HZG / Ina Frings

Für das heutige Rätsel haben wir einen Bildausschnitt gewählt. Es ist leicht ersichtlich, worum es bei dem großen Ganzen geht. Doch es zeigt auch eine besondere Charakteristik, was das Ganze unverwechselbar macht. Für bestimmte Zwecke. Damit wünschen wir viel Vergnügen beim Rätseln und ein schönes Wochenende!


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Ein bisschen Historie

Foto: HZG / R. Reshöft

brachte uns das letzte Freitagsfoto ins Blog. Mit detektivischem Gespür konnte man das Aufnahmejahr recherchieren. Die „50“ im Bild wies darauf hin, dass das Forschungszentrum in dem Jahr sein 50-jähriges Bestehen feierte.

Das war am 17. Mai 2006 – hierzu gibt es noch die damalige Pressemitteilung:

Screenshot Website HZG

Der „Tag der offenen Tür“ fand allerdings später im Jahr 2006 statt, sogar an 2 Terminen: Am 26. August in Geesthacht und am 2. September am Standort Teltow. Im Internet gibt es noch ein digitales Exemplar der damaligen Mitarbeiterzeitung „Unter uns„.


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Publications

Bieser, J., Slemr, F., Ambrose, J., Brenninkmeijer, C., Brooks, S., Dastoor, A., DeSimone, F., Ebinghaus, R., Gencarelli, C. N., Geyer, B., Gratz, L. E., Hedgecock, I. M., Jaffe, D., Kelley, P., Lin, C.-J., Jaegle, L., Matthias, V., Ryjkov, A., Selin, N. E., Song, S., Travnikov, O., Weigelt, A., Luke, W., Ren, X., Zahn, A., Yang, X., Zhu, Y., and Pirrone, N. (2017): Multi-model study of mercury dispersion in the atmosphere: vertical and interhemispheric distribution of mercury species. Atmos. Chem. Phys., 17, 6925-6955, doi:10.5194/acp-17-6925-2017

Abstract:

Atmospheric chemistry and transport of mercury play a key role in the global mercury cycle. However, there are still considerable knowledge gaps concerning the fate of mercury in the atmosphere. This is the second part of a model intercomparison study investigating the impact of atmospheric chemistry and emissions on mercury in the atmosphere. While the first study focused on ground-based observations of mercury concentration and deposition, here we investigate the vertical and interhemispheric distribution and speciation of mercury from the planetary boundary layer to the lower stratosphere. So far, there have been few model studies investigating the vertical distribution of mercury, mostly focusing on single aircraft campaigns. Here, we present a first comprehensive analysis based on various aircraft observations in Europe, North America, and on intercontinental flights.

The investigated models proved to be able to reproduce the distribution of total and elemental mercury concentrations in the troposphere including interhemispheric trends. One key aspect of the study is the investigation of mercury oxidation in the troposphere. We found that different chemistry schemes were better at reproducing observed oxidized mercury patterns depending on altitude. High concentrations of oxidized mercury in the upper troposphere could be reproduced with oxidation by bromine while elevated concentrations in the lower troposphere were better reproduced by OH and ozone chemistry. However, the results were not always conclusive as the physical and chemical parameterizations in the chemistry transport models also proved to have a substantial impact on model results.


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Job offer / Stellenangebot

Scientist (m/f)

The Institute of coastal research at the Helmholtz-Zentrum Geesthacht hosts a number of highly motivated and experienced researchers in the broad field of coastal research. A research focus lies on numerical modelling of coastal processes with specific expertise in modelling of atmosphere, ocean, marine biogeochemistry, atmosphere and ocean chemistry and sediment transport and morphodynamics on regional and coastal scales. We plan to enlarge our modeling team by an expert in discharge modelling and invite applications for a permanent position. We are looking for a highly motivated and experienced scientist (m/f) and acknowledged expert (m/f) in hydrological modeling on climate timescales. The duration of the position is 24 months.

Your tasks:

  • model development to resolve and understand the feedbacks in the coupled regional atmosphere-land-ocean systems with particular focus on coastal systems
  • further development of hydrological discharge models/river routing schemes such as HD model, TRIP
  • independently building up this research field at Helmholtz-Zentrum Geesthacht
  • conduct research about the land-ocean coupling and climate and anthropogenic system drivers on various time scales in collaboration with atmospheric and oceanic modelers
  • establishing collaboration with other Helmholtz Centers to develop research at the land-ocean-atmosphere interface
  • networking with national and international modeling communities
  • supervising of master and PhD students, collaboration with postdoctoral researchers
  • project applications and participation in national and international projects
  • publication in relevant scientific journals
  • presenting the research at international conferences and committees

Profile and qualification:

  • the successful applicant (m/f) has a university degree in Physics, Mathematics, Hydrology, Environmental Science, or related disciplines and holds a relevant PhD
  • she/he has outstanding expertise in hydrological discharge modelling on climate time scales
  • long standing experience in model development and evaluation including competence in using observational data for both purposes
  • documented expertise in working with models simulating river runoff on climate model scales and global and regional climate models
  • expertise in dealing with climate model biases and bias correction methods would be advantageous.
  • Relevant scientific expertise is documented in a range of publications in peer reviewed scientific literature.
  • the successful applicant (m/f) has excellent programming skills, familiar with FORTRAN and shell scripts within a unix/linux and High Performance Computing environment
  • excellent command of English and the ability and experience to work in an inter- and transdisciplinary environment
  • Networking with national and international modeling communities
  • the successful applicant (m/f) has participated in national and international projects and ideally also successfully applied for funding
  • contributed or independently supervised master and PhD students and guided and collaborated with postdoctoral researchers
  • and is ideally experienced in building up and leading an own research group

Closing date for applications is July, 14th, 2017.

==> detailed information for this job offer


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Herzlichen Glückwunsch! / Congratulations!

Maria Pyrina hat am letzten Freitag ihre Dissertation mit dem Titel North Atlantic Ocean decadal variability over the past millennium from climate model simulations and proxy based reconstructions erfolgreich verteidigt.

Das Hauptergebnis von Marias Arbeit bezieht sich auf die Rekonstruktion der Nordatlantischen Klimaschwankungen während der letzten 1000 Jahre. Die Ergebnisse basieren auf der jährlich aufgelösten Muschel Arctica islandica. Die Analysen zeigten, dass zwei der Fundorte von Arctica islandica ein überregionales Klimasignal repräsentieren, welches das gesamte ostatlantische Becken abdeckt (Pyrina et al., Clim Dyn (2017), doi: 10.1007/s00382-017-3536-x). Dies ist ein sehr wichtiges Ergebnis, welches aus dem marinen Proxy Arctica islandica abgeleitet werden kann. Zusätzlich hat Maria verschiedene statistische Methoden analysiert, welche angewendet werden, um großskalige Felder von Meeresoberflächentemperaturen basierend auf dem Netzwerk der Fundorte von Arctica islandica zu rekonstruieren (Pyrina et al., Clim. Past Discuss (2017), doi:10.5194/cp-2017-61). Die Überprüfung von statistischen Methoden ist ein wichtiger methodischer Schritt, da die Qualität von Klimarekonstruktionen zu einem Großteil von der angewandten statistischen Methode abhängt.

Last Friday Maria Pyrina successfully defended her doctor’s thesis North Atlantic Ocean decadal variability over the past millennium from climate model simulations and proxy based reconstructions.

One of the most important findings of Marias work relates to the reconstruction of North Atlantic climate variability during the last millennium, on the basis of annually resolved marine proxy data from the bivalve mollusk Arctica islandica. Two of the locations where Arctica islandica is collected are found to contain a broad climatic signal of the eastern Atlantic basin (Pyrina et al., Clim Dyn (2017), doi: 10.1007/s00382-017-3536-x). That is a valuable finding regarding the information that can be extracted by Arctica’s proxy records. Additionally, she assessed different statistical methods that can be applied for the reconstruction of large scale sea surface temperature patterns based on the network of Arctica islandica (Pyrina et al., Clim. Past Discuss (2017), doi:10.5194/cp-2017-61). The assessment of statistical methods is an important methodological step, as the quality of past climate reconstructions largely depends on the statistical method applied.

(Text: Sebastian Wagner, Photos: Sabine Billerbeck)


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Publications

Monika J. Barcikowska, Sarah B. Kapnick, Frauke Feser (2017): Impact of large-scale circulation changes in the North Atlantic sector on the current and future Mediterranean winter hydroclimate. Climate Dynamics, 2017, doi: 10.1007/s00382-017-3735-5

Abstract:

The Mediterranean region, located in the transition zone between the dry subtropical and wet European mid-latitude climate, is very sensitive to changes in the global mean climate state. Projecting future changes of the Mediterranean hydroclimate under global warming therefore requires dynamic climate models to reproduce the main mechanisms controlling regional hydroclimate with sufficiently high resolution to realistically simulate climate extremes. To assess future winter precipitation changes in the Mediterranean region we use the Geophysical Fluid Dynamics Laboratory high-resolution general circulation model for control simulations with pre-industrial greenhouse gas and aerosol concentrations which are compared to future scenario simulations. Here we show that the coupled model is able to reliably simulate the large-scale winter circulation, including the North Atlantic Oscillation and Eastern Atlantic patterns of variability, and its associated impacts on the mean Mediterranean hydroclimate. The model also realistically reproduces the regional features of daily heavy rainfall, which are absent in lower-resolution simulations. A five-member future projection ensemble, which assumes comparatively high greenhouse gas emissions (RCP8.5) until 2100, indicates a strong winter decline in Mediterranean precipitation for the coming decades. Consistent with dynamical and thermodynamical consequences of a warming atmosphere, derived changes feature a distinct bipolar behavior, i.e. wetting in  the north—and drying in the south. Changes are most pronounced over the northwest African coast, where the projected winter precipitation decline reaches 40% of present values. Despite a decrease in mean precipitation, heavy rainfall indices show drastic increases across most of the Mediterranean, except the North African coast, which is under the strong influence of the cold Canary Current.

 

Juan José Gómez-Navarro, Eduardo Zorita, Christoph C. Raible, Raphael Neukom (2017): Pseudo-proxy tests of the analogue method to reconstruct spatially resolved global temperature during the Common Era. Clim. Past, 13, 629-648, 2017, doi: 10.5194/cp-13-629-2017

Abstract:

This study addresses the possibility of carrying out spatially resolved global reconstructions of annual mean temperature using a worldwide network of proxy records and a method based on the search of analogues. Several variants of the method are evaluated, and their performance is analysed. As a test bed for the reconstruction, the PAGES 2k proxy database (version 1.9.0) is employed as a predictor, the HadCRUT4 dataset is the set of observations used as the predictand and target, and a set of simulations from the PMIP3 simulations are used as a pool to draw analogues and carry out pseudo-proxy experiments (PPEs). The performance of the variants of the analogue method (AM) is evaluated through a series of PPEs in growing complexity, from a perfect-proxy scenario to a realistic one where the pseudo-proxy records are contaminated with noise (white and red) and missing values, mimicking the limitations of actual proxies. Additionally, the method is tested by reconstructing the real observed HadCRUT4 temperature based on the calibration of real proxies. The reconstructed fields reproduce the observed decadal temperature variability. From all the tests, we can conclude that the analogue pool provided by the PMIP3 ensemble is large enough to reconstruct global annual temperatures during the Common Era. Furthermore, the search of analogues based on a metric that minimises the RMSE in real space outperforms other evaluated metrics, including the search of analogues in the range-reduced space expanded by the leading empirical orthogonal functions (EOFs). These results show how the AM is able to spatially extrapolate the information of a network of local proxy records to produce a homogeneous gap-free climate field reconstruction with valuable information in areas barely covered by proxies and make the AM a suitable tool to produce valuable climate field reconstructions for the Common Era.

 

Wang, J., Yang, B., Ljungqvist, F.C., Luterbacher, J., Osborn, T.J., Briffa, K.R., Zorita, E. (2017): Internal and external forcing of multidecadal Atlantic climate variability over the past 1,200 years. Nature Geoscience, 2017, doi: 10.1038/ngeo2962

Abstract:

The North Atlantic experiences climate variability on multidecadal scales, which is sometimes referred to as Atlantic multidecadal variability. However, the relative contributions of external forcing such as changes in solar irradiance or volcanic activity and internal dynamics to these variations are unclear. Here we provide evidence for persistent summer Atlantic multidecadal variability from AD 800 to 2010 using a network of annually resolved terrestrial proxy records from the circum-North Atlantic region. We find that large volcanic eruptions and solar irradiance minima induce cool phases of Atlantic multidecadal variability and collectively explain about 30% of the variance in the reconstruction on timescales greater than 30 years. We are then able to isolate the internally generated component of Atlantic multidecadal variability, which we define as the Atlantic multidecadal oscillation. We find that the Atlantic multidecadal oscillation is the largest contributor to Atlantic multidecadal variability over the past 1,200 years. We also identify coherence between the Atlantic multidecadal oscillation and Northern Hemisphere temperature variations, leading us to conclude that the apparent link between Atlantic multidecadal variability and regional to hemispheric climate does not arise solely from a common response to external drivers, and may instead reflect dynamic processes.


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Job offer / Stellenangebot

PhD Position (m/f) in numerical modelling of coastal and shelf morphodynamics

The Institute of Coastal Research at the Helmholtz-Zentrum Geesthacht investigates coastal and shelf processes including interaction between land, sea and human being. As a means to identify the potential for change, sustainability and adaptation, scientists at the institute provide the tools, assessments and scenarios for managing the vulnerable coastal and shelf landscape. Coastal and shelf mud deposits represent the proximal sink for continent-derived material during modern sea level conditions. They serve as habitat for benthic life and store large quantities of carbon, nutrients, and contaminants. Most of them initiated to develop during mid- to late Holocene. Despite of their important role in the global source-to-sink transport and ecosystem functioning, their growth dynamics and the particular natural as well as anthropogenic drivers that shape their morphology remain largely unknown.

The objective of the position is to investigate the basic driving mechanisms for morphogenesis and morphological development of large-scale (10-100 km in length) shelf mud depocenters, with particular emphasis on the impact of extreme/energetic events (e.g. storms, floods, energetic internal waves and submesoscale eddies) as well as intensive human activity (bottom trawling).

The duration of the position is 36 months.

Your tasks include:

  • analysis of existing datasets from hydrographic monitoring and sediment cores
  • applying and modifying existing numerical models to simulate sediment transport and morphodynamics of shelf mud depocenters
  • work as an integrative part of a motivated multidisciplinary team within the institute and external academic partners
  • scientific publication and presentation

Job requirements:

  • a strong background in physical oceanography, fluid mechanics, geosciences, or related disciplines
  • good scientific programming skills with FORTRAN
  • good knowledge of English (written and oral)
  • high degree of creativity and flexibility; ability to work under pressure
  • ability and willingness to participate in sea-going research
  • good communication skills and ability to work in an interdisciplinary team with sedimentologists, climatologists and physical oceanographers

The following qualifications would be desirable:

  • experience in using Unix/Linux
  • research experience on sediment transport
  • an academic publication record

Closing date for applications is July, 14th, 2017.