NOAA ENCŪ NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION US4AK7JF - ALASKA INDEX: NOTE A AUTHORITIES AIDS TO NAVIGATION WARNING - PRUDENT MARINER POLLUTION REPORTS SUPPLEMENTAL INFORMATION CAUTION - MARINERS CAUTION - DEPTHS RACON CAUTION - USE OF RADIO SIGNALS (LIMITATIONS) COLREGS, 80.1705 WATER LEVELS, CURRENTS, AND TIDES COMMENTS REQUESTED ADDITIONAL INFORMATION RADAR REFLECTORS CAUTION - TEMPORARY CHANGES CAUTION - QUALITY OF BATHYMETRIC DATA HORIZONTAL DATUM NOTES: NOTE A Navigation regulations are published in Chapter 2, U.S. Coast Pilot 9. Additions or revisions to Chapter 2 are published in the Notice to Mariners. Information concerning the regulations may be obtained at the Office of the Commander, 17th Coast Guard District in Juneau, Alaska, or at the Office of the District Engineer, Corps of Engineers in Anchorage, Alaska. Refer to charted regulation section numbers. AUTHORITIES Hydrography (from surveys of 1952-53) and topography by the National Ocean Service, Coast Survey, with additional data from the State of Alaska, the Geological Survey, and U.S. Coast Guard. AIDS TO NAVIGATION Consult U.S. Coast Guard Light List for supplemental information concerning aids to navigation. WARNING - PRUDENT MARINER The prudent mariner will not rely solely on any single aid to navigation, particularly on floating aids. See U.S. Coast Guard Light List and U.S. Coast Pilot for details. POLLUTION REPORTS Report all spills of oil and hazardous substances to the National Response Center via 1-800-424-8802 (toll free), or to the nearest U.S. Coast Guard facility if telephone communication is impossible (33 CFR 153). SUPPLEMENTAL INFORMATION Consult U.S. Coast Pilot 9 for important supplemental information. CAUTION - MARINERS Mariners are advised that in the shallow waters of the Beaufort Sea, water levels are strongly influenced by meteorological conditions. Strong offshore winds can produce water depths up to 0.8 meters (2.6 feet) less than those shown. CAUTION - DEPTHS Depths may vary as much as 1.8 meters (6 feet) due to iceberg groundings. RACON Radar Transponder Beacons or RACONS are activated by radars operating on the X-Band frequencies 9300 to 9450 MHz and when activated will emit an international morse code character which will be visible on the radar screen that activated the RACON. The effective range of the RACONS will be from 11 to 27 nautical miles. The RACONS will be maintained seasonally from 1 July to 15 September. CAUTION - USE OF RADIO SIGNALS (LIMITATIONS) Limitations on the use of radio signals as aids to marine navigation can be found in the U.S. Coast Guard Light Lists and National Geospatial-Intelligence Agency Publication 117. Radio direction-finder bearings to commercial broadcasting stations are subject to error and should be used with caution. COLREGS, 80.1705 International Regulations for Preventing Collisions at Sea, 1972. The entire area of this chart falls seaward of the COLREGS Demarcation Line. WATER LEVELS, CURRENTS, AND TIDES Real-time water levels, tide predictions, and tidal current predictions are available on the internet from NOAA's Center for Operational Oceanographic Products and Services (CO-OPS) at https://tidesandcurrents.noaa.gov/water_level_info.html and https://tidesandcurrents.noaa.gov/currents_info.html. COMMENTS REQUESTED NOAA encourages users to submit inquiries, discrepancies, or comments about this chart via NOAA's ASSIST tool at https://www.nauticalcharts.noaa.gov/customer-service/assist/. ADDITIONAL INFORMATION Additional information can be obtained at www.nauticalcharts.noaa.gov. RADAR REFLECTORS Radar reflectors have been placed on many floating aids to navigation. Individual radar reflector identification on these aids has been omitted from this chart. CAUTION - TEMPORARY CHANGES Temporary changes or defects in aids to navigation are not indicated. See Local Notice to Mariners. CAUTION - QUALITY OF BATHYMETRIC DATA The areas represented by the object M_QUAL (Quality of data) are approximate due to generalizing for clarity. Caution is advised, particularly for nearshore navigation or voyage planning. M_QUAL represents areas of uniform quality of bathymetric data. The CATZOC (Category of zone of confidence in data) attribute of M_QUAL provides an assessment of the overall zone of confidence. HORIZONTAL DATUM The NOAA ENC references the World Geodetic System of 1984 (WGS-84). For charting purposes, the horizontal control of the current realization of WGS-84 is functionally equivalent to the International Terrestrial Reference Frame 2020 (ITRF2020) at the meter level for charts at scales of 1:5,000 or smaller. END OF FILE