Koldewey Station, Ny-Ålesund/Spitsbergen: projects/activities

The objective of our work with arctic terrestrial plants and with algae is to study the range of climate adaptation as is expressed in special ultrastructure of cells and tissues, in photosynthetic metabolism, in antioxidative and sun screen compounds under a cold and reduced PAR / UV-B environment (climate different to alpine conditions). This is a comparison of ecophysiological processes already worked out mainly from high alpine plants, which live periodically under stronger cold and under different light regimes, especially higher UV-B and PAR irradiation. We want to find out, whether adaptations found in some alpine organisms occur similarly in polar forms.

The effects of stratospheric ozone depletion and of global warming on the marine biosphere are still underexplored, especially in the Arctic. Seaweeds are very important primary producers but are strongly susceptible to enhanced UV radiation and elevated temperatures, especially their spores. The UV susceptibility of spores has previously been invoked to determine the depth distribution of seaweeds. Therefore, we will investigate the effect of different radiation and temperature conditions on the ultra-structure, physiology and biochemistry of spores from various brown and green algae growing in different water depths. Moreover, we will study competition between zoospores of various species of brown macroalgae in order to get an insight about biotic factors structuring seaweed communities and also to explain more clearly the present seaweed zonation pattern.

The project IOANA proposes to better understand the intimate coupling between ozone mixing ratios and particulate nitrate isotopic characteristics. Ozone Depletion Events which occur in Arctic coastal locations shortly after sunrise are a subject of interest per se (scientifically challenging for two decades) but also provide a context in which ozone mixing ratios are highly variable, enabling to characterize the dynamic of correlation and process studies with a resolution of a day. This is a first step towards the use of the isotope tool in reconstructions of the oxidative capacity of the atmosphere. This programme is a preparation of the IPY-OASIS project and propose to coodinate a set of collaborations than will be effective duing the International Polar Year.

The project aims at producing an ENVISAT-1 mission-long monitoring of the inorganic chlorine (Cly) and fluorine (Fy) loading in the Earth’s middle atmosphere, based on FTIR vertical column abundance measurements of the key related species HCl, ClONO2, HF and COF2 at 10 ground-based NDSC sites distributed worldwide. These Cly and Fy inventories will be completed with ClO and OClO measurements expected as Level-2 products from ENVISAT-1. The column abundances of the source gases CFC-12 and HCFC-22 will be used to place the stratospheric Cly and Fy evolution in perspective with the more complete sets of organic chlorinated and fluorinated compounds measured at the ground by the in situ networks NOAA-CMDL and AGAGE. The assimilation of the retrieved geophysical data bases will be performed through 3-D model calculations incorporating physical, chemical and transport characteristics of the global atmosphere.

The present project aims at the geophysical validation, from pole to pole and on the long term, of key ozone-related level-2 products (O3, NO2, BrO, OClO, and ClO) from GOMOS, MIPAS and SCIAMACHY onboard ENVISAT-1, and at a contribution to the maturation of the related level-1b-to-2 data processors. Application data processing will be used to convert level-2 data into a more suitable format for validation and scientific end-users. The respective performances of the ENVISAT data products, and their sensitivity to various relevant parameters, will be investigated from the Arctic to the Antarctic, over a variety of geophysical conditions. The impact of these performances on specific atmospheric chemistry studies will be emphasised. The pseudo-global investigations will rely on correlative studies of ENVISAT data with high-quality ground-based, in situ and balloon observations associated with the Network for the Detection of Stratospheric Change (NDSC).

The project will provide a long-term, pseudo-global validation support to the ENVISAT-1 atmospheric measurements, based on mutually consistent high-quality solar and lunar observations from FTIR spectrometers operated at primary and a number of complementary NDSC stations. The validation is limited to a number of target species, most of which are primary NRT or OL level-2 products of the mission, with focus on NOy components: O3, NO2, NO, N2O, HNO3, HNO4, H2CO, CO and CH4. Synergistic use will be made of column and profile data from MIPAS, GOMOS and SCIAMACHY. The ground network will deliver mean vertical column abundances for all target species with NDSC-type quality, and height profile information for some target gases as secondary products to the PI's home institute, where the correlative analyses with the ENVISAT-1 products will be done. Asynoptic mapping tools will support the validation efforts.

SOGE is an integrated system for observation of halogenated greenhouse gases in Europe. There are two objectives: (1) To develop a new cost-effective long-term European observation system for halocarbons. The results will be in support of the Kyoto and the Montreal protocols,in assessing the compliance of European regions with the protocol requirements. In particular the observation system will be set up to: - detect trends in the concentrations of greenhouse active and ozone-destroying halocarbons; - verify reported emissions and validate emission inventories; - develop observational capacity for all halocarbons included in the Kyoto protocol (PFC, SF6) for which this is presently not yet existing; - develop a strategy for a cost-effective long-term observation system for halocarbons in Europe. (2) To predict and assess impacts of the halocarbons on the climate and on the ozone layer. This implies extensive exploitation of existing data. The impact assessment will be aimed at providing guidance for development of the Kyoto protocol and to the further development of the Montreal protocol mendments, by: - modelling impacts of halocarbons on radiative forcing and their relative importance for climate change; - modelling impacts of emissions of CFCs and HCFCs on the ozone layer.

The main specific objectives of UFTIR are: (1) To revise and homogenise the analyses of available experimental data for providing consistent time series of distinct tropospheric and stratospheric abundances of the target gases using new inversion algorithms. A common strategy for retrieval and characterisation of the vertical distributions of the target gases from FTIR ground-based measurements will be established. (2) To provide quantitative trends and associated uncertainties for the target gases over about the last decade, as a function of latitude throughout Western Europe, focusing on the troposphere. (3) To integrate the data in model assessments of the evolutions of tropospheric abundances. The measured burden and changes of the tropospheric gases will be compared with 3D model simulations, in order to help developing the latter, assist in explaining potential causes for the observed changes and to assess the consistencies between the trends at the surface to the free troposphere and lowermost stratosphere, and the agreement with known evolutions of emissions. UFTIR will make the community prepared to deliver tropospheric data for validation and synergistic exploitation of new satellite experiments like ENVISAT.

In december 2001 the SAGE III experiment was successfully launched. The NASA science team of the SAGE III experiment has announced the Koldewey-Station in Ny-Aalesund as "anchor site" for validation, especially for such parameters as optical depth, aerosol extinction profiles and ozone profiles. Because of time coincidence NASA apprechiates support for the prospected validation activities for ENVISAT. This should be also considered as contribution to the NASA accepted project "Ground based Validation of SAGE III by the NDSC Primary Station at Ny-Ålesund, Spitsbergen" for SOLVE-2.

During the spring/summer transition, sea ice and snow properties change considerably in response to warming and the eventual reversal of temperature gradients within the snow and ice. Snow melt water percolates down towards the colder snow/ice interface, where it refreezes to form superimposed ice. On sea ice this process occurs probably longer and more intensive than on land, because throughout the summer the ice and underlying seawater is always colder than the snow. In Antarctica superimposed ice may actually form layers of some decimeters in thickness. The objective of this study is to investigate the main processes and boundary conditions for superimposed ice formation, in recognition of its importance for Antarctic sea ice, and its possible importance for Arctic sea ice in case of environmental changes due to future climate change. This will be performed by means of modeling as well as by combined measurements of the temporal evolution of snow and ice properties and the energy budget.

As a result of the increasing atmospheric CO2 levels and other greenhose gases due to anthropogenic activities, global and water temperature is rising. The objectives of our project might be summarized as follows: I. To measure the activity of the enzymatic systems involved in carbon, nitrogen and phosphorus uptake (carbonic anhydrase, nitrate reductase and alkaline phosphatase) in selected macroalgae. To assess the optimal concentration of inorganic nitrogen and phosphorus for growth and photosynthesis. To study the total concentration of carbon and nitrogen metabolites in the macroalgae (proteins, total carbohydrates, and lipids) in order to define the possible existence of nutrient limitation. II. To simulate the conditions of climate change, represented as CO2 enrichment and increasing UV radiation, on the activity of carbon, nitrogen and phosphorus uptake mechanisms. III. To screen the activity of the enzymatic systems previously detailed in macroalgae from the Konjsfjord, in order to know their nutritional state.

ASTAR, Arctic Study of Tropospheric Aerosol and Radiation is a a joint German (AWI Potsdam) - Japanese (NIPR Tokyo) campaign with participation from NASA LaRC Hampton, VA (USA). In addition to AWI, NIPR, and NASA LaRC the following institutions contributed to the project: Hokkaido University (Japan), Nagoya University (Japan), Norwegian Polar Institute Tromsoe/ Longyearbyen (Norway), NILU Kjeller (Norway), MISU Stockholm (Sweden), NOAA-CMDL Boulder, CO (USA) and Max Planck Institute for Aeronomy Katlenburg-Lindau (Germany). The campaign is based on simultaneous airborne measurements from the German research aircraft POLAR 4 and ground-based measurements in Ny-Ålesund. The main goals of the project are - to measure aerosol parameters of climate relevance, like extinction coefficient, absoprtion coefficients and phase function. - to create an Arctic Aerosol Data Set for climate impact investigation by using the regional climate model HIRHAM. - to carry out comparison measurements with the SAGE II (Stratospheric Aerosol and Gas Experiment) and the ground based Raman-Lidar.

In preparation to the launch of the SAGE III experiment in March 2001, NASA and the European Union performed the SOLVE / THESEO-2000 campaign, which had three components: (i) an aircraft campaign using the NASA DC-8 and ER-2 airplanes out of Kiruna/Sweden, (ii) launches of large stratospheric research balloons from Kiruna, (iii) validation excercises for the commissioning phase of SAGE III. The German Arctic research station Koldewey in Ny-Ålesund/Spitsbergen contributes to (i), (ii), and (iii) by performing measurements of stratospheric components like ozone, trace gases, aerosols (PSCs), temperature and winds. The measurement results were transmitted quasi online to the flight planning center in Kiruna, in order to allow a better directing of the air plane flights. In addition the Koldewey-Station has been designated a validation anchor site for the SAGE III validation. The activities are organized within a NASA accepted proposal of ground-based validation support by the NDSC Primary Station at Ny-Ålesund, Spitsbergen and by a SAGE III validation working group for Ny-Ålesund. The main observation periods are from December 1999 to March 2000.

In order to get detailed vertical ozone profiles above the range of standard electrochemical ozonesondes (typically 35 km), a radiosonde together with an optical ozonesensor is launchend with a special plastic foliage balloon. The balloon payload consists of a digital radiosonde (DFM 90) using GPS for altitude measurements and a two channel filter spectrometer (optical sensor) to measure the vertical ozone distribution up to more than 40 km altitude. The ozone profiles obtained by the optical sensors will be compared with ground-based microwave and lidar ozone observations as well as with the standard balloon-borne ozone measurements with electrochemical ozone sensors.

The aim of the project is to study the properties (radiative effects, composition) of aerosols using FTIR emission spectroscopy. To determine seasonal changes in aerosol properties the measurements will be carried out year round on a weekly schedule.

The current scientific knowledge does not allow estimating accurately the surface radiative forcing caused by tropospheric aerosols and their influence on the evolution of the Earth climate. The radiative forcing depends on the optical properties of the aerosols at solar and thermal infrared wavelengths. These optical properties depend, in turn, on the chemical composition and size of the aerosols. Remote sensing with passive radiation sensors operating in the above-mentioned spectral ranges allows to measure the optical properties of the aerosols and to characterise their temporal variability. These data are needed for regional climate simulations of the Arctic, particularly for delineating the impact of the Arctic haze phenomenon. In this project, a synergetic effort will be made to obtain information about the radiative and microphysical properties of springtime arctic aerosols. Therefore, a polarisation-spectrometer for the solar spectral range, which is currently developed at the Free University of Berlin as a variant of the FUBISS spectrometer, will be operated from the surface in coincidence with the Fourier Transform InfraRed-spectrometer (FTIR) installed at Ny-Aalesund by the AWI. The former instrument measures the intensity and polarisation of the scattered solar radiation from the visible to the near-infrared. The latter measures the radiation emitted by the Atmosphere itself in the thermal infrared window region. Together, they thus provide a wealth of information about the aerosol optical properties at the interesting wavelengths (spectral optical depth, single-scattering albedo, and asymmetry factor of the phase function), which will allow inferring the aerosol microphysical properties. Complementary measurements of the aerosol microphysical properties will be provided by an aerosol volatility analyser, which is maintained by the University of Leeds and will also be brought to Ny-Aalesund. This instrument comprises a fast response scanning volatility system and an optical particle counter. From the thermal response of the aerosol number and the change in the size distribution conclusions can be inferred about the chemical composition and the state of mixing of aerosols as a function of size.

Aim of the project is to develop a cost-effective long-term European observation system for halocarbons and to predict and assess impacts of the halocarbons on the climate and on the ozone layer. Beside the routine observations within the NDSC it is planned to perform with FTIR (Fourier Transform Infrared Spectroscopy) absorption measurements of CFCs (e.g. SF6, CCl2F2, CHF2Cl) and related species on much more observation days.

The aim of the project is to perform solar and lunar absorption measurements of atmospheric trace gases for the valdation of the SCIAMACHY satellite. Besides the routine observations within the NDSC it is planned to perform more intense measurements, especially during the satellite overpasses.