Projects/Activities

The full list of projects contains the entire database hosted on this portal, across the available directories. The projects and activities (across all directories/catalogs) are also available by country of origin, by geographical region, or by directory.

Displaying: 161 - 180 of 324 Next
161. UV-radiation and its impact on genetic diversity, population structure and foodwebs of arctic freshwater

The aim of this international project is to measure and model arctic UV-radiation and assess the effects on freshwater planktonic organisms and foodwebs. The fieldwork and experiments are conducted at Ny-Alesund, Spitsbergen. The specific aim of our participation is to study the food web effects of UV-B stress by means of in-situ enclosure studies. In the laboratory we found that UV-B stressed algal cells may increase in volume and form a thicker cell wall. These changes in the algal cells may reduce their digestibility by zooplankton. Further the role of photopigments (like melanin and carotenoids), present in some zooplankters, will be studied in relation to the survival of these animals at high UV-B exposure. Research activities Grazing experiments with Daphnia pulex (melanic and hyaline) are performed in in-situ enclosures (under different UV exposures) in the Brandal Lagune during July. The green alga Chlamydomonas will be incubated in-situ under different UV exposures to assess the potential use of this alga as a biodosimeter for UV-B. Further the survival of melanic and hyaline daphnids will be tested in-situ.

Biological effects UV radiation survival photopigments Exposure Food webs Reproduction phytoplankton zooplankton
162. Goose breeding ecology: overcoming successive hurdles to raise goslings

Determining ecological constraints for Barnacle Geese during the Arctic summer to understand individual breeding success. Geese are individually marked, measured and observed over their lifetime in order to study individual reproductive strategies and their consequences. Also the interaction between the geese and their food plants is studied in detail. Research activities Every year, during summer, fieldwork in Ny Ålesund, every two years counting geese along Norden-skioldkysten. Both areas are located on Spitsbergen.

Biology breeding success Biodiversity geese
163. The ecological interaction between the Spitsbergen whaling and walrus hunting activities and the marine ecosystem in the 17th and 18th centuries

In the seventeent and eighteenth centuries intensive European whaling and walrus hunting took place in the waters around Spitsbergen, with many stations on the coast of the islands. The hunt was carried out in areas along the edge of pack ice and is therefore very sensitive to changes in the ice situation and climate. When, around 1650, climate and ice distribution changed, whales moved to the north. The whaling stations in the south of Spitsbergen were abandoned when stations in the north were still functioning. When, later, the ice situation deteriorated in the north as well, the stations were abandoned there too. Shore whaling changed into pelagic whaling. Because of these whaling and walrus hunting activities two very numerous large mammals were largely depleted and almost disappeared from the Spitsbergen waters. The pelagically feeding Greenland Right Whale and the bentically feeding walrus, whose initial stocks are estimated at 46,000 Greenland Right Whales and 25,000 walrus, were eliminated. This elimination has caused a major shift in the foodweb. The plankton feeding seabirds and polar cod strongly increased because of the elimination of the Greenland Right Whale, and the eider ducks and bearded seals increased because of the decrease of the number of walruses. This development has led to the enormous amount of seabird rookeries on the West coast of Spitsbergen.

whaling Biology whales Populations hunting Biodiversity Seabirds Food webs Ecosystems walrus Marine mammals
164. Breeding success of the long-tailed Skua

The ecology and breeding success of the Longtailed skua (Stercorarius longicaudus) and the Brown skua (Catheracta lonnbergi) is studied in a longterm programme. The difference in allometric growth between the different species and populations of skuas is interesting when it is related to the ecology and distribution history of these species and populations. Skuas have a dynamic distribution history and an opportunistic way of living. Populations of the same species in different localities have often a different ecology. Therefore, studies on different populations of the same species are carried out.

Biology Populations breeding success skua Biodiversity Seabirds Reproduction
165. Breeding success of the Brown Skua

The ecology and breeding success of the Long-tailed skua (Stercorarius longicaudus) and the Brown skua (Catheracta lonnbergi) is studied in a longterm programme. The difference in allometric growth between the different species and populations of skuas is interesting when it is related to the ecology and distribution history of these species and populations. Skuas have a dynamic distribution history and an opportunistic way of living. Populations of the same species in different localities have often a different ecology. Therefore, studies on different populations of the same species are carried out.

Biology Populations breeding success skua Biodiversity Seabirds Reproduction
166. Entangled Sulphur and Carbon cycles in Phaeocystis dominated Ecosystems (ESCAPE)

The principal aim of the project is to establish a link between the marine carbon and sulphur cycles, for which the marine phytoplankton taxon Phaeocystis sp. was chosen as a model organism. This colony forming alga is an important source of the volatile organic sulphur compound dimethyl sulphide (DMS), and its dense blooms can act as a carbon sink. By combining the expertise of researchers working on the carbon and sulphur cycles a thorough inventory of these chemicals will be made. This should result in a better understanding of the role of Phaeocystis blooms in the escape of DMS in the atmosphere and of carbon from the photic zone, and consequently of its role in climate control.

Sources Biology carbon cycle DMS Climate variability algal blooms Phaeocystis Climate change sulphur cycle
167. Energy balance of the Greenland Ice Sheet

Analysis of the energy balance terms obtained during the measuring campaign in 1991 at Greenland. It deals with profile and turbulence measurements, RASS-SODAR observations and radiation measurments.

mass balance Climate variability Climate Climate change Ice Ice sheets
168. Land ice, climate change and sea level

Land ice forms an important component of the climate system. Sea level variations are closely related to the total ice volume. Purpose of the research project is to obtain a better understanding of how glacier fluctuations and climate change are linked. This is a prerequisite to make more accurate predictions of future sea level.

Glaciers Climate variability Climate Climate change sea-level change Ice Ice sheets
169. Circulation and transports in the Atlantic Ocean

Elaboration of DUTCH-WARP [Deep and Upper Transport, Circulation and Hydrography-WOCE Atlantic Research Programme] in the frame of WOCE: deep circulation of thermal structure of surface water in the Iceland Basin; continuation of the application of ARGOS buoys; implementation of satellite altimetry of the North Atlantic Ocean; eastern boundary current of the North Atlantic Ocean in the Bay of Biscay as contribution to WOCE (1992-1998)

Climate variability remote sensing Climate change Oceanography circulation Ocean currents WOCE
170. Holocene of Nova Scotia and New Brunswick, Canada

Study of the Holocene development in the coastal area of Nova Scotia and New Brunswick (Canada), in relation to sea-level movements, isostatic movements and climate development, particularly for the last 4500 years. Use of stratigraphical and sedimentological methods and of 14C-dating.

Geology Climate variability isostatic adjustment stratigraphy Climate change sea-level change Holocene Sediments
171. Paleeoecology and (periglacial) eolian sediment transfer in the ice-sheet marginal zone of southwestern Greenland (Kangerlussuaq region)

The project aims at reconstructing the environmental history in the interior Kangerlussuaq region since deglaciation. Focus is placed on the lacustrine and eolian sediments to decipher climate evolution in terms of temperature, evaporation- precipitation balance and phases of high- wind speed events. The overall objectives are to build a high-resolution (decadal-to-century scale) chronostratigraphic framework for past climate variability from the analysis of organic-rich lake sediments and peat filled basins using a variety of sediment analysis techniques (magnetostratigraphy, grainsize, sedimentfractionation techniques, AMS 14C dating, diatom-, pollen- and macrofossil analysis) and sedimentology. Research activities diatom analysis, pollen analysis, magnetic susceptibility, automated correlation techniques, grainsize, organic chemistry, sediment fractionation techniques, AMS radiocarbon dating, sedimentology, mapping, sediment transport and erosion measurements/monitoring, micro-meteorology, vegetation mapping, pollen rain studies, diatom salinity training sets, limnology

Glaciers Geology eolian Climate variability Climate sedimentology Climate change Quaternary geology Ice sheets Geochemistry Sediments paleeoecology geomorphology periglacial paleolimnology
172. Geomorphology, climate and specific phenomena in the periglacial

Periglacial conditions have characterized the geomorphological development of river systems and have activated eolian processes during the Quarternary ice ages in Europe. Frost and melt mechanisms have also caused deformations on micro and macro scale in soil and sediments. Specific periglacial phenomena are indicative for (paleo-) climatic conditions

Geology Climate variability paleoclimatology Climate Climate change geomorphology periglacial
173. Health effects of increased UV exposure

Besides some beneficial effects of UV exposure, i.e. skin tanning and vitamin D production, UV ex-posure can have deleterious effects on human health. Deleterious effects are a.o. skin cancer, skin aging, wrinkling, cataract, snow blindness, and effects on the immune system. The objectives of this project are especially aimed at the detection of UV effects on the human immune system and as a consequence of the UV induced immunomodulation effects on the resistance to infections and tumors. Research activities Research activities are focussed at laboratory animal studies, studies with human volunteers, epidemiology and mathematical modelling.

Biological effects epidemiology UV radiation immunology Exposure Human health
174. Prediction of extreme offshore structure response

The development of methods for the accurate prediction of the extreme response of non-linear dynamic systems which use less computer time than presently commom methods.

structure response technology Modelling offshore
175. Palaeobotany and palynology

In the wake of topical research issues such as global change and energy resources, one can recognize two priority targets for the study of fossil plant remains: - insight into the role of land plants and phytoplankton as monitors, recorders, motors and moderators of climatic and environmental change; -insight into the predictive value of organic remains with respect to genesis, composition, occurrence, quality and quantity of fossil fuel reserves. In harmony with these targets, current research at the Laboratory of Palaeobotany and Palynology (LPP) is aimed to provide for basic contributions to the palaeoecological study and interpretation of Palaeozoic, Mesozoic and Cenozoic plant life. Four interconnected areas of scientific emphasis are currently distinguished: - biotic change: documentation and causal analysis of changes of past plant biota in terrestrial and marine environments, both at short and long time-scales; - selective preservation: identification of the biological, physical and chemical factors that determine selective preservation of organic matter during transport, sedimentation and burial; - methodology: development and introduction of new analytical methodology relevant to the study and interpretation of fossil plant remains; - systematics: generation and compilation of systematic data aimed at the accurate identification and classification of fossil plant remains. Overview of results LPP strives after a balance between the study of land plant remains and organic-walled marine phytoplankton (mainly dinoflagellates). Research objectives are related to both short (latest Pleistocene-Holocene) and long time-scales (late Palaeozoic-Cenozoic). Short time-scales Modern land plant communities can be understood only in the light of their history since the onset of the last deglaciation (15,000 yr BP). In western and southern Europe this history is governed by the climatically induced spread of forest communities and their subsequent recession as man's influence expanded. Through fine-scale analysis (temporal and spatial, as well as systematic), of assemblages of microscopic and macroscopic plant remains, research concentrates on the accurate discrimination between autogenic, climatically induced, and anthropogenic vegetational change in contrasting physiographic entities: (1) crystalline mountains in France and the Iberian peninsula; (2) landscapes characterized by Pleistocene-Holocene eolian (sand, loess) deposition in the Netherlands and Germany; (3) fluvial plains in the Netherlands; (4) littoral landscapes in Portugal, and (5) Arctic landscapes of Spitsbergen, Jan Mayen and Greenland. Following earrlier research experiences with respect to the palaeoecological analysis of pollen assemblages from the Vosges (France), in the research period special attention was given to deciphering the complex, altitude related, late Pleistocene-Holocene pollen signals from other low mountain ranges. Results have demonstrated that the spatial distribution of vegetation patterns can be followed through time by recognizing: (1) common time-proportionate trends in pollen values, and (2) local pollen components characteristic for altitudinal vegetation zones and lake/mire development. Long time-scales For the recognition and evaluation of biotic change on long time-scales, LPP concentrates on the study of land plant and phytoplankton records from sedimentary successions that contrast with respect to: (1) time of formation (selected late Palaeozoic, Mesozoic and Cenozoic intervals); (2) paleotectonic and palaeogeographic history (intracratonic; passive and active plate margins); (3) depositional environment (terrestrial to deep-marine); and (4) biogeographic provinciality. Temporal and spatial distribution patterns of plant remains are explored for proxy variables indicative of terrestrial and marine environmental change. Investigated variables include land temperature, humidity, precipitation, runoff, sea-level, sea surface temperature, salinity, nutrient supply, productivity, organic burial rate and CO2 level. In the review period particular attention has been given to the development of palaeoecological models of dinoflagellate cyst distribution in marine sediments. It has been shown that: (1) the potential of dinoflagellates in Mesozoic and Cenozoic time-resolution may frequently exceed that of planktonic foraminifera and calcareous nannoplankton, and (2) dinoflagellates can be applied in novel ways to further the environmental understanding of depositional sequences and sedimentary cycles defined by physical (seismic, sedimentological) analysis. Although research related to global change programmes is generally restricted to the Late Tertiary-Quaternary, there is one notable exception. It is recognized that a better understanding of the patterns and processes of past mass extinctions can contribute to an understanding of present and future man-induced extinction processes. Work by LPP concentrates on the profound biotic crises at the Permian/Triassic (P/Tr) and Cretaceous/Tertiary (K/T) junctions. Study of the P/Tr land plant record has now revealed ecosystem collapse in the terrestrial biosphere. At the K/T junction, it has been demon-strated that dinoflagellates have remained immune to extinction. Independent of configurations predicted by meteorite-impact or massive volcanism, therefore, palynological studies enable high-resolution reconstruction of environmental change, both during pre-crisis times and the phases of K/T ecosystem decline and recovery.

Geology palaeobotany Climate variability Climate Climate change palynology Sediments
176. Tundra

Overall objective is to obtain net fluxes for carbon and freshwater water from an Arctic catchment under base-case and global change scenarios. Objective of the Vrije Universiteit Amsterdam is to study the temporal and patial variability in floodplain sediment balance over the last 2000 years. Research activities: Selected areas in the Usa basin will be studied in detail, both in the zones of continuous and discontiunous permafrost. Fieldwork was and will be conducted in the summers of 1998 and 1999. At selected field sites, the present day processes of river erosion and deposition will be evaluated and the natural evolution and variation of amount and rate of erosion and deposition will be determined for the last 2000 years.

Pathways erosion sediment balance Soils Hydrography Catchment studies carbon flux Climate variability freshwater flux Discharges Spatial trends Climate change Geochemistry Sediments Temporal trends
177. Permafrost in the Usa Basin: distribution, characterisation, dynamics and effects on infrastructure

- To support the further development of a geocryological database for the Usa Basin (East-European Russian Arctic), including key characteristics of permafrost such as distribution, coverage, temperature, active layer, etc. - To create GIS-based permafrost maps at the scale of 1:1,000,000 for the entire Usa Basin and at 1:100,000 for selected key sites. - To reconstruct the history of permafrost dynamics at key sites in the region over the last thousands of years using palaeoecological analysis and radiocarbon dating of peat deposits, and over the last few decades using remote sensing imagery and/or monitoring (base case scenario). - To predict permafrost dynamics at key sites in the region under future conditions of climate change (20-100 yrs), using a 1-dimensional permafrost model (future global change scenario). - To assess the effects of permafrost dynamics under base case and global change scenarios on urban, industrial and transportation infrastructure in the Usa Basin. Research activities Based on several representative sites, late Holocene permafrost dynamics will be characterized using palaeoecological techniques. Variability in permafrost conditions over the last few decades will be studied based on the available data from long-term monitoring station records and from a time series of remote sensing images (optional). Mathematical modelling of permafrost dynamics will be carried out for at least two sites and a forecast of permafrost degradation in the area under anticipated climate warming will be developed. The likely effects of permafrost degradation upon regional infrastructure (inhabited localities, heat and power engineering, coal and ore mines, oil and gas extracting complex, pipelines and railways) will be analyzed using a GIS approach. GIS data layers on permafrost dynamics and infrastructure will be compared in order to delimitate high risk areas based on existing infrastructure and anticipated permafrost degradation. Hereafter, the created GIS may serve as a basis for more detailed forecasting of permafrost dynamics under both natural and anthropogenic climate changes in lowland and alpine areas of the East-European Russian Arctic.

geocryology Geology palaeoecology Soils Catchment studies Mapping Geophysics Climate variability Climate Spatial trends Environmental management Climate change Modelling Ice GIS Permafrost Oil and Gas Temporal trends permafrost dynamics infrastructure
178. Late Quaternary paleoceanography of the Denmark Strait Overflow Pathway

The global thermohaline circulation is driven by sinking of cold, dense surface waters in the Greenland and Norwegian Seas and its replacement by warmer surface water from lower latitudes. This global circulation system, the conveyor belt, is the main regulator of global climate. Even slight disturbances of this delicate system will cause significant climate changes, especially for NW Europe. While the current hydrographical situation and associated overflow pathways are well-documented, paleoceanographic studies of the Greenland and Faroe/Shetland (F/S) overflow pathways are still scarce. The F/S pathway is presently the subject of study of the MAST program (ENAM project). This project focusses on the late Quaternary overflow history of the important East Greenland pathway. High resolution multichannel sleevegun seismic data recently collected by the Geological Survey of Greenland and Denmark (GEUS) allowed identification of suitable box- and piston-coring sites. Results from the high-resolution cores, allowing direct correlation with regional atmospheric changes documented in the Greenland ice-cores will provide new information on causes and mechanisms of climate change. The continental slope and rise off SE-Greenland can be considered as a potential key area for paleoceanographic and paleoclimatic studies, since: 1) The area is located in the immediate vicinity of the Denmark Strait arctic gateway for water mass exchange between the Arctic and Atlantic ocean. Recent hydrographic measurements (Dickson 1994) demonstrate the important role of the area with regard to hydrographic processes contributing to the formation of NADW. 2) The seafloor morphology and information from multichannel seismic recording shows the presence of numerous large detached sediment drifts and other drift-related features, which will provide important paleoceanographic information as outlined before. 3) The distribution and architecture of the sediment drifts is also affected by down-slope processes transporting upperslope/shelf sediments of mainly glacial origin. Thus the area offers an unique opportunity to study the sediment drifts both with regard to the (paleo)oceanic flow regime and the climatically-inherited signal from the down-slope sediment input. Research activities: All research is directed towards documentation of high resolution natural climate variability during the late Quaternary. Separate topics include: 1. Seismic/sidescan sonar studies 2. High resolution quantitative micropaleontology (planktonic/benthic foraminifera, diatoms, calcareous nannoplankton, dinoflagellates) 3. High resolution stable oxygen/carbon isotope studies 4. DNA studies on planktonic foraminifera (with University of Edinburgh)

Climate variability Climate Climate change Oceanography Ice cores micropaleontology Ocean currents paleoceanography
179. Atmospheric transport modelling of HM/POPs over Europe

The aim of this project is to assess the deposition of HM/POP over Europe and to evaluate models. Within the framework of UN-ECE, EMEP Meteorological Synthesising Centre-East (MSC-E Moscow) organised in co-operation with RIVM, a model intercomparison for operational transport models on HM in 1995. In this intercomparison the RIVM will participate with the TREND-model. Results of the intercomparison will also be reported to the OSPAR commission. A model comparison for POPs will follow later. The RIVM/EUROS model is extended with soil and surface water modules in order to improve the description of the exchange process of POPs (deposition and re-emission). With the model, long-term averages of the deposition and accumulatation of POPs are described and scenario-studies can be carried out. In the first instance, Lindane and B(a)P will be taken as examples of POPs dominantly present respectively in the gas phase and attached to particles. When emissions are available the calculations are extended to other POPs.

Pathways Atmospheric processes Heavy metals PAHs Long-range transport Contaminant transport Modelling Emissions Persistent organic pollutants (POPs) Pesticides Atmosphere
180. Climate development in Polar areas during the last 1000 years

This project studies the climate development in polar areas during the last 400 years using the results of pollen analysis of soil samples collected in the Arctic regions, and written information collected in Dutch archives. Dutch sailors were sailing in Arctic waters already long before Willem Barentsz tried to find the northeast passage to China and India in the 1590s. They reported their observations to their principals and these reports are sometimes preserved. In this way written sources with much information about may aspects of the Atlantic Arctic are kept in reports in the Dutch archives. In these reports valuable information about the weather in the last 400 years is registered and also if serial these data can be interpreted as climate information. In combination with the information of the pollendiagrams of the collected soil samples, it will be possible to reconstruct the climate development in the Arctic in the last 400 years.

Soils Climate variability paleoclimatology Climate Climate change