* Provideniya
Provideniya is located on Provideniya Bay on the Chukotka Peninsula. Overall depths in the bay are 30-35m and 9m near the berths. Medical and tug assistance are available and navigational information can be obtained from the Provideniya Hydrobase.
The port information provided above is derived from an INSROP survey (WP-17). Continuous change in the Russian Arctic makes the functions of the ports and even their availability to foreign ships unpredictable.
(3) Radio Communication
A radio communication system is installed in the NSR for use in ship traffic control and broadcasting information on ice conditions and the like. This system is divided at longitude 125｡? into two broad zones nationwide. In the west, communication centers are established at Murmansk, Dikson and Amderma; in the east, they are located in Tiksi, Pevek and Mys Shmidta. All ships navigating the NSR are required to maintain close contact with the MOH and escort icebreakers using the medium-frequency (MF) range, to report ship locations regularly and receive route instructions. In addition to the conventional radio communication equipment specified in international conventions, vessels on the NSR should be equipped with VHF radio equipment (122.5MHz) to communicate with aircraft and convoy ships, equipment for sound recording and reception of facsimiles, and a satellite communication station.
Radio communications may from time to time be adversely affected by magnetic storms, which recur in cycles of 25 to 30 days. A single magnetic storm usually lasts for a few hours, but may occasionally interfere with radio communications for over a day. Magnetic storms are most powerful in the regions where the aurora is seen, and particularly in a band from 72｡?o 74｡? off the north coast of Novaya Zemlya, as well as the north coast of Severnaya Zemlya and at the mouths of the Ob and Yenisey Rivers.
Different types of radio communication are used for different ranges and purposes. Radio communications are used at relatively short distances, as in ship-to-ship, ship-to-airport or ship-to-shore communication. For more long-distance communication, such as communication between ships navigating different regions and communication between the ship and its country of registration, satellite communications are used. Two systems* for satellite communications are in use in the NSR: an international standard system and a Russian system. The international system is the INMARSAT satellite system and the Russian proprietary system is called OKEAN.
The INMARSAT system covers the NSR area with two geostationary satellites, IOR at east longitude 64°over the Indian Ocean and POR at east longitude 178°over the Pacific Ocean. However, because the NSR passes through high latitudes, these satellites sit low above the horizon, rendering communications difficult in some areas (Figure 4.2-10). Outside the curve of 0°elevation above the horizon, the satellite is hidden below the horizon, rendering communication theoretically impossible. In the western Laptev Sea, which lies at a high latitude of about 120°, both IOR and POR sink below the horizon, placing this area beyond the reach of INMARSAT communications. Even in regions where the satellite's angle of elevation is above 0°, ship superstructures, deck machinery and appliances may cast a shadow on satellite antenna, adversely influencing the ability to receive signals and obliging the ship's crew to remedy the situation by turning and retrying communication.
Russia's OKEAN network, on the other hand, covers the NSR with three satellites, one hovering over the Atlantic Ocean at 40｡? longitude, a second over the Indian Ocean at 80｡? and a third over the Pacific Ocean at 140｡?. The Russian system covers the entire NSR, with at least one of these three satellites above the horizon at all times (Figure 4.2-11). Few of the IMMARSAT ship receivers are compatible with the OKEAN system and unfortunately only a few devices are capable of the OKEAN system; Russia's Volna-C and Iceberg, Norway's Saturn-3C and Japan's JUE-45. None of these devices is widely used.
