the island occur most years, weather permitting. During these expeditions, tens of thousands of radio contacts are made with people in several parts of the world. At high seas, landing is only possible with a helicopter. Pictures of Märket are shown on QSL cards. The official prefix for use on the Finnish side is OJ0 call sign prefix for Märket Reef. An OJ0 vanity callsign can be obtained, for a fee, from Traficom.fi, the Finnish Transport and Communication Agency. Amateurs with licenses in countries supporting CEPT can operate from the reef while using the OJ0/ prefix in front of one's own call sign. All radio activity on the island is by visitors on DX-peditions. When the Finnish part of the reef was given its special status in amateur radio, in the late 1960s the lighthouse keeper himself became a licensed amateur radio operator, who initially used the call OH0MA. On the Swedish side of Märket Reef, the call signs 8S9M and SI8MI have been used. Climate Märket has a continental climate affected by oceanic influences; it has a reputation for being one of the windiest places in Finland. A meteorological station has been managed by the lighthouse keepers since 1896, and an automatic station of the Finnish Meteorological Institute was inaugurated on November 10, 1977, shortly before its automation. The effect of the sea is very important to the climate of the island; thermal inertia dramatically reduces the temperature fluctuations during the year compared to those of the continent, and to a lesser extent, those of the central part of Fasta Åland, the largest island of the archipelago of Åland. Märket holds five records for daytime temperatures among Finnish weather stations, all in the period between November 29 and January 1, with on December 15, 2006, and on December 31, 1975. The average yearly temperature is roughly and is one of the highest in Finland, with the month of January being milder than on the continent ( on average), and a warm summer ( on average in July). The island is drier than the mainland; the average annual rainfall does not usually surpass . See also List of divided islands Kataja Bogskär and Lågskär, other detached Finnish islands Utö, Finland Nuorgam Fort Blunder, an American fort mistakenly built in Canada References Gallery External links 2021 OJ0D Satellite Radio DXpedition to Märket https://sral.info/2018/06/19/market-calling/ 2007 Radio DXpedition to Märket Configurable map centred