Infrastructure

Infrastructure and additional site information:

ICOS Östergarnsholm welcomes individual researchers and research groups to come to our measurement site and use existing infrastructure for their own measurements and collaborations. Regardless if it is a research visit with placement of equipment on our measurement tower, hut or in the form of ship-based measurements passing by our site we welcome you and will do our best to accommodate your needs.

Figure 1: Measurement masts at the site.
Figure 2: Photograph of the site infrastructure taken from the 10 m tower showing the measurement hut, power supply system components and also cables from the towers and the hut which contains data loggers.

The measurement site is about 4 km from the eastern coast of Gotland located on Östergarnsholm which is a small, flat island which stretches about 2 km in a W-E and N-S direction respectively. The maximum depth of the sea within 1 km radius is about 30 m. The station location in WGS84 coordinates (Latitude, Longitude) are:

30 m tower: 57.43010 N, 18.98415 E

SAMI and Seabird sensor: 57.42333 N, 18.99450 E

Wave buoy (operated by FMI): 57.41667 N, 19.05333 E

Figure 3: Sketch of the island Östergarnsholm, east coast of Gotland and location of the 30 m tower, water buoy sensor and wave rider buoy location.
Figure 4: Aerial photograph of the southern tip of the island with locations of the tower, measurement hut, diesel generator and harbor at Östergarnsholm indicated at the map (figure adapted from Lantmäteriet).

Östergarnsholm is a remote island reachable by boat from Gotland run by local citizen on contract with Uppsala University. The site is usually visited about every second month for maintenance if weather and ocean conditions are permitting this. The buoy sensors are typically exchanged twice per year with factory calibrated instruments. There is no ice cover on the site, however the harbor in Herrvik on the east coast of Gotland, where the boat is starting from, can freeze in the wintertime making the site seasonally difficult to access. The typical annual atmospheric temperature range is from -20oC to +20oC on the site.

Figure 5: Photograph of the boat usually transporting personnel and equipment between Herrvik and Östergarnsholm.

There is no grid power on Östergarnsholm but the site has its own power supply consisting of wind turbines, solar panels and a backup diesel generator owned by Uppsala University and monitored by an external company. It is an autonomous system delivering 12 V, 24 V and 230 V. The total electricity capacity available on the site is about 2.5kW (in operation since November 2016). The diesel generator is placed approximately 400 m north from the measurement tower (close to the old harbor) to minimize influence on the measurements.

Figure 6: Photograph of the diesel generator located close to the old harbor at Östergarnsholm
Figure 7: Photograph of the small measurement hut and in the background solar panels, wind turbines as part of the autonomous power supply system available on the site.

There is a small unheated measurement hut shared by Uppsala University, Stockholm University and visitors with an available space of approximately 6.5 m2. For temporary storage there is also some limited space inside a stainless-steel shipping container used for a large battery bank as part of the power supply system. There is data connection in the form of 3G modem on the site. There is no motor vehicles on the island. There is a cart to pull equipment from the harbor to the site.

Figure 8: Power supply container with solar panels and two wind turbines and far in the background the backup diesel generator is also visible.