Svalbard: projects/activities

Changes in surface reflection at the arctic tundra at Ny-Ålesund, Svalbard (79 N) were monitored during the melting season 2002 using a low cost multispectral digital camera with spectral channels similar to channels 2, 3, and 4 of the Landsat Thematic Mapper satellite sensor. The camera was placed 474 m above sea level at the Zeppelin Mountain Research Station and was programmed to take an image automatically every day at solar noon. To achieve areal consistency in the images (which is necessary for mapping purposes) the images were geometrically rectified into multispectral digital orthophotos. In contrast to satellite images with high spatial resolution the orthophotos provide data with high spatial and high temporal resolution at low cost. The study area covers approximately 2 km2 and when free of snow, it mainly consists of typical high arctic tundra with patchy vegetation and bare soil in between. The spectral information in the images was used to divide the rectified images into maps representing different surface classes (including three subclasses of snow). By combining classified image data and ground measurements of surface reflectance, a model to produce daily maps of surface albedo was developed. The model takes into account that snow-albedo decreases as the snow pack ages; and that the albedo decreases very rapidly when the snow pack is shallow enough (20-30 cm) to let surface reflectance get influenced by the underlying ground. Maps representing days with no image data (due to bad weather conditions) were derived using interpolation between pixels with equal geographical coordinates. The time series of modeled albedo-maps shows that the time it takes for the albedo to get from 80% to bare ground levels varies from less than 10 days in areas near the coast or in the Ny-Ålesund settlement till more than 70 days in areas with large snow accumulations. For the entire study area the mean length of the 2002 melting period was 28.3 days with a standard deviation of 15.1 days. Finally, the duration of the snowmelt season at a location where it is measured routinely, was calculated to 23 days, which is very close to what is the average for the last two decades.

The German Aerospace Center (DLR) Bi-spectral Infrared Detection (BIRD) small satellite is a technology demonstrator of new infrared push-broom sensors dedicated to recognition and quantitative characterisation of thermal processes on the Earth surface. BIRD was successfully piggy-back launched on October 22, 2001 with an Indian Polar Satellite Launch Vehicle (PSLV-C3) into a circular sun-synchronous orbit with an altitude of 572 km and a North - South local equator crossing time at 10:30 h. Besides cameras working in the visible and near infrared spectral range there are two cameras working in the middle infrared (MIR, 3.4 – 4.2 µm) and in the thermal spectral range (TIR, 8.5 – 9.3 µm) respectively. The objective is to validate these two cameras in cooperation with the Koldewey-Station in Ny-Ålesund. Therefore meteorological and aerological data as well as radiation measuring data will be used.

The subject is to determine the horizontal distribution of aerosol and trace gases by airborne measurements with the Gulfstream III (transarctic flight), ground based measurements in Ny Ålesund (Koldewey Station, Rabben) and satellite measurements with SAGE II / SAGE III. Objective is to get vertical and horizontal aerosol profiles, to research the trace gase variations in the Arctic and to compare remote sensing und in situ measurements.

By launching several hundred ozonesondes and by ozone lidar measurements at many Arctic and sub-Arctic stations, one of them Ny-Ålesund, the stratospheric chemical ozone loss will be determined. The launches of all stations will be coordinated by analysis of trajectory calculations based on analysis and forecast wind fields. The aim is to get as many ozone sounding pairs as possible, each of them linked by trajectories in space and time. A statistical description of the ozone differencies given by the first and the second measurement of individual sonde pairs will yield the chemical ozone loss with spatial and time resolution. Four similar campaigns took place in the Arctic and in the mid-latitudes covering the time period of Januar to March in each of the last four winters. In the first three winters high ozone depletion rates (20 - 50 ppbv per day) were determined in some height levels within the polar vortex. In the height level of the ozone maximum an integrated ozone loss (during the winter) in the order of 60 % have been found. These are record ozone losses for the Arctic polar region. In the last winter the ozone depletion rates had been much lower due to moderate temperatures in the stratosphere.

The active layer, the annually freezing and thawing upper ground in permafrost areas, is of pivotal importance. The moisture and heat transfer characteristics of this layer also determine the boundary layer interactions of the underlying permafrost and the atmosphere and are therefore important parameters input for geothermal or climate modeling. Finally, changes in the characteristics of the permafrost and permafrost related processes may be used as indicators of global ecological change provided the system permafrost-active layer-atmosphere is understood sufficiently well. The dynamics of permafrost soils is measured with high accuracy and high temporal resolution at our two sites close to Ny-Ålesund, Svalbard. Using these continuous data we quantify energy balance components and deduce heat transfer processes such as conductive heat flux, generation of heat from phase transitions, and migration of water vapor.

Due to the high organochlorine concentrations reported in Arctic top predators, and the potential transport of contaminants with the drifting sea-ice in the Arctic, organisms constituting lower trophic levels living in association with sea-ice have been proposed as susceptible of uptake of high loads of organic pollutants. The present project studies the organochlorine occurrence in organisms living in the marginal ice zone north of Svalbard and in the Fram Strait. This includes both ice fauna (ice-amphipods), zooplankton, polar cod and different seabird species foraging in the marginal ice zone. Our objectives are to investigate: *The bioaccumulation of organochlorines in ice-associated amphipods in relation to diet preference, spatial variation due to sea ice drift route, size, sampling year, uptake and distribution within the body. *Comparison of organochlorine contamination in pelagic and ice-associated organisms at the similar trophic position, to investigate the effect of sea ice as a transporter and concentrator of pollutants. *Spatial variation in zooplankton species, related to differences in water masses and exposure to first year or multi year sea ice. *The contamination load in different seabirds feeding in the marginal ice zone, in relation to diet choice and estimated trophic position, taxonomically closeness and the induction of hepatic CYP P450 enzymes.

The study covers many areas of ecotoxicology research on polar bears. Monitoring of POP levels and studies of effects on endocrine disruption, immune system, reproduction, and demography are all parts of the study.

The project aims to describe the environmental status of marine sediments in van Mijenfjorden. This to provide baseline data of contaminants and biodiversity, as well as for monitoring of eventual contamination from industrial activities (coal mining).

Investigation of benthic faunal communities for: taxon distribution/ biodiversity mapping; examination of effects of glacial and physical disturbance on community structure; relation between faunal structure and sediment contaminants.