The Östergarnsholm site has been running semi-continuously since 1995 with the aim to study the marine atmospheric boundary layer.

Within ICOS Östergarnsholm will become a combined ecosystem and oceanic station.

The measurement site Östergarnsholm (57°26′N, 18°59′E) is located 4 km from the eastern coast of Gotland.

Östergarnsholm is a small, flat island which stretches about 2 km in the W-E and N-S direction respectively. The southern part is very flat and rises only a few meters above sea surface.

The site is operated today by Uppsala University by the group of Anna Rutgersson who is as well the station principal investigator for the ICOS measurements.

Station principal investigator Anna Rutgersson.	Research engineer Leonie Esters.	Research engineer Erik Nilsson.

ICOS Sweden invites other research groups to use the infrastructure. Please fill in our web form.

The vegetation consists of a few single trees (in the N-E corner) as well as low herbs and grass together with small bushes.

With a mean annual air temperature of 7°C and a mean annual precipitation of 383 mm (data period 1961-1990, SMHI station Östergarnsholm) the climate is characterized after Köppen as a Cfb-climate, i.e. humid temperate with mild summers and mild winters.

The cold water in spring and summer gives dominantly stable atmospheric stratification during April to July. Despite low winter temperatures, the sea surrounding Östergarnsholm has ice free conditions throughout the year. Higher rates of cyclonic activity in winter result generally in higher wind speeds in winter than in summer.

The carbon cycle represented by the Östergarnsholm site shows a strong seasonal variation with marine carbon uptake from April to October, and emissions from November to March.

A 30 m tall tower is situated around 1 m above sea level on the southernmost tip of the small flat island Östergarnsholm. Two buoys are located 1 km (SAMI sensor) and 4 km (Wave rider buoy) southeast of the tower, respectively.

The tower is equipped with instruments measuring profiles of wind, temperature, CO₂ and humidity, as well as turbulent fluxes of momentum, heat, water vapor and CO₂. Presently, also precipitation, air pressure, and incoming solar radiation are measured at the site.

The Wave rider buoy, operated by the Finnish Meteorological Institute, measures wave parameters and water temperature at 0.5 m depth. CO₂, water temperature, oxygen, and salinity are measured at 4 m depth by a SAMI sensor and a Seabird.

Furthermore, aerosols are continuously measured in an additional 10 m tall tower operated by Stockholm University.

For more detailed information please contact Prof Anna Rutgersson.

2016
• Andersson A., Rutgersson A., Sahlée E. (2016): Using eddy covariance to estimate air-sea gas transfer velocity for oxygen. Journal of Marine Systems, 159:67-75, DOI:10.1016/j.jmarsys.2016.02.008
• Parard G., Charantonis A., Rutgersson A. (2016): Using satellite data to estimate partial pressure of CO₂ in the Baltic Sea. Journal of Geophysical Research - Biogeoscience, 121:1002-1015, DOI:10.1002/2015JG003064
• Svensson N., Bergström H., Sahlée E., and Rutgersson A. (2016): Stable atmospheric conditions over the Baltic Sea: model evaluation and climatology. Boreal Environmental Research, 21:387-404.
• Wu L., Rutgersson A., Sahlée E., and Larsén X.G. (2016): Swell impact on wind stress and atmospheric mixing in a regional coupled atmosphere-wave model. Journal of Geophysical Research - Oceans, 121:4633-4648, DOI:10.1002/2015JC011576

2015
• Hahmann A.N., Vincent C.L., Peña A., Lange J., and Hasager C.B. (2015): Wind climate estimation using WRF model output: method and model sensitivities over the sea. International Journal of Climatology, 35:3422-3439, DOI:10.1002/joc.4217
• Högström U., Sahlée E., Smedman A.-S., Rutgersson A., Nilsson E., Kahma K.K., and Drennan W.M. (2015): Surface stress over the ocean in swell-dominated conditions during moderate winds. Journal of the Atmospheric Sciences, 72:4777-4795, DOI:10.1175/JAS-D-15-0139.1, PDF [1.6MB]
• Parard G., Charantonis A., Rutgersson A. (2015): Remote sensing the sea surface CO₂ of the Baltic Sea using the SOMLO methodology. Biogeosciences, 12:3369-3384, DOI:10.5194/bg-12-3369-2015, PDF [5.4MB]
• Song J., Fan W., Li S., and Zhou M. (2015): Impact of surface waves on the steady near-surface wind profiles over the ocean. Boundary-Layer Meteorology, 155:111-127, DOI:10.1007/s10546-014-9983-6
• Vieira V.M.N.C.S., Sahlée E., Jurus P., Clementi E., Pettersson H., and Mateus M. (2015): Improving estimations of greenhouse gas transfer velocities by atmosphere-ocean couplers in Earth-system and regional models. Biogeosciences Discussions, 12:15901-15924, DOI:10.5194/bgd-12-15901-2015, PDF [1.6MB]
• Vincent C.L. and Hahmann A.N. (2015): The impact of grid and spectral nudging on the variance of the near-surface wind speed. Journal of Applied Meteorology and Climatology, 54:1021-1038, DOI:10.1175/JAMC-D-14-0047.1, PDF [4.2MB]
• Wu L., Rutgersson A., Sahlée E., Larsén X.G. (2015): The impact of waves and sea spray on modelling storm track and development. Tellus A 67:27967, DOI:10.3402/tellusa.v67.27967, PDF [8.6MB]

2014
• Andersson A., Rutgersson A., and Sahlée E. (2014): Using a high-frequency fluorescent oxygen probe in atmospheric eddy covariance applications. Journal of Atmospheric and Oceanic Technology, 31:2498-2511, DOI:10.1175/JTECH-D-13-00249.1, PDF [1.2MB]
• Nilsson E.O., Sahlée E., and Rutgersson A. (2014): Turbulent momentum flux characterisation using extended multiresolution analysis. Quarterly Journal of the Royal Meteorological Society, 140:1715-1728, DOI:10.1002/qj.2252

2013
• Högström U., Rutgersson A., Sahlée E., Smedman A.-S., Hristov T.S., Drennan W.M., and Kahma K.K. (2013): Air-sea interaction features in the Baltic Sea and at a pacific trade-wind site: An inter-comparison study. Boundary-Layer Meteorology, 147:139-163, DOI:10.1007/s10546-012-9776-8
• Norman M., Parampil S.R., Rutgersson A., and Sahlée E. (2013): Influence of coastal upwelling on the air-sea gas exchange of CO₂ in a Baltic Sea basin. Tellus B, 65:21831, DOI:10.3402/tellusb.v65i0.21831, PDF [2.9MB]

2012
• Belcher S.E., Grant A.L.M., Hanley K.E., et al. (2012): A global perspective on Langmuir turbulence in the ocean surface boundary layer, Geophysical Research Letters, 39:L18605, DOI:10.1029/2012GL052932, PDF [2MB]
• Nilsson E.O., Rutgersson A., Smedman A.-S., and Sullivan P.P. (2012): Convective boundary-layer structure in the presence of wind-following swell. Quarterly Journal of the Royal Meteorological Society, 138:1476-1489, DOI:10.1002/qj.1898
• Norman M., Rutgersson A., Sørensen L.L., and Sahlée E. (2012): Methods for estimating air-sea fluxes of CO₂ using high-frequency measurements. Boundary-Layer Meteorology, 144:379-400, DOI:10.1007/s10546-012-9730-9

2011
• Rutgersson A., Smedman A.-S., and Sahlée E. (2011): Oceanic convective mixing and the impact on air-sea gas transfer velocity. Geophysical Research Letters, 38:L02602, DOI:10.1029/2010GL045581, PDF [0.2MB]
• Wesslander K., Hall P., Hjalmarsson S., Lefevere D., Omstedt A., Rutgersson A., Sahlée E., and Tengberg A. (2011): Observed carbon dioxide and oxygen dynamics in a Baltic Sea coastal region. Journal of Marine Systems, 86:1-9, DOI:10.1016/j.jmarsys.2011.01.001

2010
• Carlsson B., Papadimitrakis Y., and Rutgersson A. (2010): Evaluation of a roughness length model and sea surface properties in the Baltic Sea. Journal of Physical Oceanography, 40:2007-2024, DOI:10.1175/2010JPO4340.1, PDF [1.4MB]
• Rutgersson A. and Smedman A.-S. (2010): Enhanced air-sea CO₂ transfer due to water-side convection. Journal of Marine Systems, 80:125-134, DOI:10.1016/j.jmarsys.2009.11.004
• Rutgerson A., Sætra Ø., Semedo A., Carlsson B., and Kumar R. (2010): Impact of surface waves in a Regional Climate Model. Meteorologische Zeitschrift, 19:247-257, DOI:10.1127/0941-2948/2010/0456

2009
• Carlsson B., Rutgersson A., and Smedman A.-S. (2009): Impact of swell on a regional atmospheric climate model. Tellus, 61:527-538, DOI:10.1111/j.1600-0870.2009.00403.x
• Carlsson B., Rutgersson A., and Smedman A.-S. (2009): Investigating the effect of a wave-dependent momentum flux in a process oriented ocean model. Boreal Environment Research, 14:3-17, PDF [1MB]
• Högström U., Smedman A., Sahlée E., Drennan W.M., Kahama K.K., Pettersson H., and Zhang F. (2009): The atmospheric boundary layer during swell - a field study and interpretation of the turbulent kinetic energy budget for high wave ages. Journal of the Atmospheric Sciences, 66:2764-2779, DOI:10.1175/2099JAS2973.1, PDF [1MB]
• Rutgersson A., Norman M., and Åström G. (2009): Atmospheric CO₂ variation over the Baltic Sea and the impact on air-sea exchange. Boreal Environment Research, 14:238-249, PDF [1MB]
• Semedo A., Sætra Ø., Rutgersson A., Kahma K.K., and Pettersson H. (2009): Wave induced wind in the marine boundary layer. Journal of the Atmospheric Sciences, 66:2256-2271, DOI:10.1175/2009JAS3018.1, PDF [1.4MB]
• Smedman A.-S., Högström U., Sahlée E., Drennan W.M., Kahama K.K., Pettersson H., and Zhang F. (2009): Observational study of marine atmospheric boundary layer characteristics during swell. Journal of the Atmospheric Sciences, 66:2747-2763, DOI:10.1175/2009JAS2952.1, PDF [1MB]

2008
• Högström U., Sahlée E., Drennan W.M., et al. (2008): Momentum fluxes and wind gradients in the marine boundary layer - a multi platform study. Boreal Environment Research, 13:475-502, PDF [4MB]
• Rutgersson A., Norman M., Schneider B., Pettersson H., and Sahlée E. (2008): The annual cycle of carbon-dioxide and parameters influencing the air-sea carbon exchange in the Baltic Proper. Journal of Marine Systems, 74:381-394, DOI:10.1016/j.jmarsys.2008.02.005
• Sahlée E., Smedman A.-S., Högström U., and Rutgersson A. (2008): Reevaluation of the bulk exchange coefficient for humidity at sea during unstable and neutral conditions. Journal of Physical Oceanography, 38:257-272, DOI:10.1175/2007JPO3754.1, PDF [1MB]
• Sahlée E., Smedman A.-S., Rutgersson A., and Högström U. (2008): Spectra of CO₂ and humidity in the marine atmospheric surface layer. Boundary-Layer Meteorology, 126:279-295, DOI:10.1007/s10546-007-9230-5

2007
• Rutgersson A., Carlsson B., and Smedman A.-S. (2007): Modelling sensible and latent heat fluxes over sea during unstable, very close to neutral conditions. Boundary-Layer Meteorology, 123:395-415, DOI:10.1007/s10546-006-9150-9
• Smedman A.-S., Högström U., Sahlée E., and Johansson C. (2007): Critical re-evaluation of the bulk transfer coefficient for sensible heat over the ocean during unstable and neutral conditions Quarterly Journal of the Royal Meteorological Society, 133:227-250, DOI:10.1002/qj.6, PDF [0.6MB]
• Smedman A.-S., Högström U., Hunt J.C.R., and Sahlée E. (2007): Heat/mass transfer in the slightly unstable atmospheric surface layer. Quarterly Journal of the Royal Meteorological Society, 133:37-51, DOI:10.1002/qj.7, PDF [0.4MB]

2006
• Högström U., Smedman A.-S., and Bergström H. (2006): Calculation of wind speed variation with height over the sea. Wind Engineering, 30:269-286, DOI:10.1260/030952406779295480
• Smedman A.-S., Bumke K., Högström U., et al. (2006): Precipitation and evaporation budgets over the Baltic Proper: Observations and modelling. Journal of Atmospheric and Ocean Science, 10:163-191, DOI:10.1080/17417530500513756

2005
• Johansson C., Hennemuth B., Bösenberg B., Linné H., and Smedman A.-S. (2005): Double-layer structure over the Baltic Sea. Boundary-Layer Meteorology, 114:389-412, DOI:10.1007/s10546-004-1671-5
• Rutgersson A., Omstedt A., and Chen Y. (2005): Evaluation of the heat balance components over the Baltic Sea using four gridded meteorological databases and direct observations. Nordic Hydrology, 36:381-396

2004
• Guo Larsén X., Smedman A.-S., and Högström U. (2004): Air-sea exchange of sensible heat over the Baltic Sea. Quarterly Journal of the Royal Meteorological Society, 130:1-25, DOI:10.1256/qj.03.11, PDF [0.8MB]
• Högström U. and Smedman A.-S. (2004): Accuracy of sonic anemometers: Laminar wind-tunnel calibrations compared to atmospheric in situ calibrations against a reference instrument. Boundary-Layer Meteorology, 111:33-54, DOI:10.1023/B:BOUN.0000011000.05248.47
• Sjöblom A. and Smedman A.-S. (2004): Comparison between eddy-correlation and inertial dissipation methods in the marine atmospheric boundary layer. Boundary-Layer Meteorology, 110:141-164, DOI:10.1023/A:1026006402060
• Smedman A.-S., Hunt J.C.R., and Högström U. (2004): Effects of shear sheltering in a slightly stable atmospheric boundary layer with strong shear. Quarterly Journal of the Royal Meteorological Society, 130:31-50, DOI:10.1256/qj.03.68, PDF [0.6MB]

2003
• Guo Larsén X., Makin V., and Smedman A.-S. (2003): Comparison of modelled and measured shearing stress over the Baltic Sea. Global Atmos. Ocean System, 9(3)
• Hennemuth B., Rutgersson A., Bumke K., Clemens M., Omstedt A., Jacob D., and Smedman A.-S. (2003): Net precipitation over the Baltic Sea for one year using several methods. Tellus, 55:352-367, DOI:10.1034/j.1600-0870.2003.00020.x
• Mahrt L., Vickers D., Fredrickson P., Davidson K, and Smedman A.-S. (2003): Sea-surface aerodynamic roughness. Journal of Geophysical Research: Oceans, 108:3171, DOI:10.1029/2002JC001383, PDF [0.2MB]
• Sjöblom A. and Smedman A.-S. (2003): Vertical structure in the marine atmospheric boundary layer and its implication for the inertial dissipation method. Boundary-Layer Meteorology, 109:1-25, DOI:10.1023/A:1025407109324
• Smedman A.-S., Högström U., and Sjöblom A. (2003): A note on velocity spectra in the marine boundary layer. Boundary-Layer Meteorology, 109:27-48, DOI:10.1023/A:1025428024311
• Smedman A.-S., Guo Larsén X., Högström U., Kahma K.K., and Pettersson H. (2003): The effect of sea state on the monmentum exchange over the sea during neutral conditions. Journal of Geophysical Research, 108:3367, DOI:10.1029/2002JC001526, PDF [0.2MB]
• Smedman A.-S., Högström U., Bergström H., Johansson C., Sjöblom A., and Guo Larsén X. (2003): New findings concerning the structure of the marine atmospheric boundary layer over the Baltic Sea - possible implications for wind energy installations. Journal of Wind Engineering, 27:431-447, DOI:10.1260/030952403773617427

2002
• Högström U., Hunt J.C.R., and Smedman A.-S. (2002): Theory and measurements for turbulence spectra and variances in the near neutral surface layer. Boundary-Layer Meteorology, 103:101-124, DOI:10.1023/A:1014579828712
• Sjöblom A. and Smedman A.-S. (2002): The turbulent kinetic budget over the sea. Journal of Geophysical Research: Oceans, 107:3142, DOI:10.1029/2001JC001016, PDF [0.5MB]

2001
• Johansson C., Smedman A.-S., Högström U., Brasseur J.G., and Khanna S. (2001): Critical test of the validity of Monin-Obukhov similarity during convective conditions. Journal of the Atmospheric Sciences, 58:1549-1566, DOI:10.1175/1520-0469(2001)058<1549:CTOTVO>2.0.CO;2, PDF [0.3MB]
• Johansson C., Smedman A.-S., Högström U., and Brasseur J.G. (2001): Reply. Journal of the Atmospheric Sciences, 59:2608-2614, DOI:10.1175/1520-0469(2002)059<2608:R>2.0.CO;2, PDF [0.2MB]
• Rutgersson A., Smedman A.-S., and Omstedt A. (2001): Measured and simulated sensible and latent heat fluxes at two marine sites in the Baltic Sea. Boundary-Layer Meteorology, 99:53-84, DOI:10.1023/A:1018799227854
• Rutgersson A., Smedman A.-S., and Högström U. (2001): Use of conventional stability parameters during swell. Journal of Geophysical Research: Oceans, 106:27117-27134, DOI:10.1029/2000JC000543, PDF [1.8MB]
• Rutgersson A., Bumke K., Clemens M., Foltescu V., Lindau R., Michelson D., and Omstedt A. (2001): Precipitation estimates over the Baltic Sea: Present state of the art. Nordic Hydrology, 32:285-314, DOI:10.2166/nh.2001.017

2000
• Källstrand B., Bergström H., Højstrup J., and Smedman A.-S. (2000): Meso-scale wind field modifications over the Baltic Sea. Boundary-Layer Meteorology, 95:161-188, DOI:10.1023/A:1002619611328
• Rutgersson A. (2000): A comparison between long term measured and modeled sensible heat and momentum flux using a High Resolution Limited Area Model (HIRLAM). Meteorologische Zeitschrift, 9:29-37

1999
• Bergström H. and Smedman A.-S. (1999): Wind climatology at a well-exposed site in the Baltic Sea. Journal of Wind Engineering, 23:133-142
• Högström U., Smedman A.-S., and Bergström H. (1999): A case study of two-dimensional stratified turbulence. Journal of the Atmospheric Science, 56:959-976, DOI:10.1175/1520-0469(1999)056<0959:ACSOTD>2.0.CO;2, PDF [0.2MB]
• Smedman A.-S., Högström U., Bergström H., Rutgersson A., Kahma K.K., and Pettersson H. (1999): A case-study of air-sea interaction during swell conditions. Journal of Geophysical Research:Oceans, 104:25833-25851, DOI:10.1029/1999JC900213, PDF [1.8MB]

1997
• Källstrand B. and Smedman A.-S. (1997): A case study of the near-neutral coastal internal boundary-layer growth: Aircraft measurements compared with different model estimates. Boundary-Layer Meteorology, 85:1-33, DOI:10.1023/A:1000475315106
• Smedman A.-S., Högström U., and Bergström H. (1997): The turbulence regime of a very stable marine airflow with quasi-frictional decoupling. Journal of Geophysical Research: Oceans, 102:21049-21059, DOI:10.1029/97JC01070, PDF [1MB]

1996
• Smedman A.-S., Bergström H., and Grisogono B. (1996): Evolution of stable internal boundary layers over a cold sea. Journal of Geophysical Research: Oceans, 102:1091-1099, DOI:10.1029/96/JC02782, PDF [0.9MB]
• Smedman A.-S., Högström U., and Bergström H. (1996): Low-level jets - a decisive factor for off-shore wind energy siting in the Baltic Sea. Wind Engineering, 20:137-147