Geographic Notice

Introduction/Additional information:

Introduction:

The purpose of the Geographic Notice is to transmit information that pertains to a region or area, for example a security zone, an area of fog, or dredging operations. The areas that are being defined can be circles, rectangles, polygons, or sectors. They can also be defined as a simple point or series of points (polyline). The Geographic Notice message can be made up of multiple subareas in which case the total area is the union of the subareas. This message can also be used to convey advisory lines or tracks (using the polyline subarea); however, the Route Information message should be used for recommended or directed routes.

Additional Information / usage notes:

The information is time-dependent (i.e., has start date/time and duration). If a Geographic Notice (except for a cancellation message – Notice Description 126) is received without a valid start date/time and duration then it should be discarded.
When the current month is December and the notice start month is January, the notice start year shall be the current year plus one; the notice start year shall be the current year in all other cases.
The message may be transmitted prior to the start time/date to allow for advance notice. To avoid confusion, it should not be transmitted more than one day in advance.
The message should not be transmitted beyond the designated end date/time except for a cancellation message. A cancellation message can be transmitted before the designated end date/time using the same Message Linkage ID with an Notice Description of 126 (cancellation), a Duration = 0, and start time fields all set to “not available.”
Presentation software should automatically remove the Geographic Notice from the display after the end date/time or upon receipt of a cancellation message.
Up to 5-slot messages can be created, but messages with more than three slots should be avoided. Messages with more slots are less likely to be received due to RF noise or packet collision.
A circular sub-area (Type 0) with a zero radius (scale factor should also be set to 0) is a point that can be used as a node in a polyline/polygon. This is used when more precision is needed than is possible using the points in the polyline/polygon subarea (the trade-off is more subareas and a longer message). If several points are submitted within one Geographic Notice, the link field shall be used to indicate if the points are related to a polyline(s) or polygon(s).
Polyline/polygon sub‐areas (Type 3 or 4) must follow immediately after a circle/point sub-area (Type 0 sub-area with 0 radius) in the same Geographic Notice message. The point defines the start of the line segments. If more than five points are needed for a polyline/polygon, then additional polyline/polygon sub‐areas can be used. However, they must follow immediately after the first polygon sub‐area and be contained in the same Geographic Notice message.
The polyline/polygon sub‐area (Type 3 or 4) should be used to create a polyline/polygon. However, if more precision is needed to specify the points in the polyline/polygon then the circle/point sub‐area (Type 0 with radius set to zero) can be used, one sub‐area per point. All points (sub‐areas of Type 0) must occur in sequence and be contained within the same message. The polyline/polygon is formed by connecting the points.
Polylines could be formed with a mixture of subarea type 0 and type 3 but shall start with subarea type 0. The link indicator shall be 1 whereas the last points/polyline link indicator shall be 0.
Polygon could be formed with a mixture of subarea type 0 and type 4 but shall start with subarea type 0. The link indicator shall be 2 whereas the last points/polyline link indicator shall be 0. The last point (subarea type 0) or last point of the polygone (subarea type 4) shall be connected to the first point of the shape (closing the shape)
Distances and bearings between points in the Geographic Notice should be calculated using Rhumb lines not Great Circles.
The Message Linkage ID and the source MMSI can be used to link additional text (e.g., a separate Linked Text message). This information must be included in both the Geographic Notice and additional Linked Text message.
The total area defined by one Geographic Notice (one Message Linkage ID) is the union of all of the sub‐areas contained in the message.
If the same Message Linkage ID is retransmitted with different sub‐areas and/or times the presentation software should replace the old Area with the new.
The Message Linkage ID must be unique across all ASMs to which it applies. In this way, the Message Linkage ID and Source MMSI are connected to the same text message.
A message version number is encoded as part of the message; If the received version number is different than what the display system has been programmed for, a message should be displayed to the operator indicating the mismatch in the version.
All directions are relative to True North, all positions are WGS‐84 Datum, and all distance calculations should be in accordance with IEC 61993‐2 Annex G

Permitted as from:

25/06/2020

Registrant:

Physical link:

AIS

Message number (0=VDES-VDE):

DAC or VPFI:

200

FI / Message ID:

Version:

Technical point of contact:

State:

proposal

Number of slots (max):

Last modified:

29/01/2021 - 23:19

Reporting Rate:

Depending on the conditions

Timeout 3 times the duration / 30 minutes

Details:

	Parameter		Bit	Description
	Message ID		6	Identifier for Message 8; always 8
	Repeat Indicator		2	Used by the repeater to indicate how many times a message has been repeated. Default = 0; 3 = do not repeat any more
	Source ID		30	MMSI number
	Spare		2	not used, should be set to zero, reserved for future use
Binary data	Designated Area Code		10	DAC=200
	Function Identifier		6	FI=42
	Version indicator		3	The version number of the message default = 0, rest for future use
	Spare		3	not used, should be set to zero, reserved for future use
	Message Linkage ID		10	A source specific running number, unique across all binary messages equipped with Message Linkage ID. Used to link additional information to the message by a Text Description message. The Message Linkage ID and the source MMSI uniquely identify the sent message. 1 – 1,023; 0 = not available = default.
	Notice Description		7	Notice Description as per Table 9. Set to 0 – 127 according to description. If 127, there must be associated text (see Table 8).
	Start time of area	UTC month	4	UTC month of the Area start. 1 – 12; 0 = UTC month not available = default; 13 – 15 (reserved for future use).
		UTC day	5	UTC day of the Area start. 1 – 31; 0 = UTC day not available = default.
		UTC hour	5	UTC hour of the Area start. 0 – 23; 24 = UTC hour not available = default; 25 – 31 (reserved for future use).
		UTC minute	6	UTC minute of the Area start. 0 – 59; 60 = UTC minute not available = default;61 – 63 (reserved for future use.)
	Duration		18	Minutes until end of Geographic Notice, measured from start date and time of Geographic Notice. Maximum duration is 262.142 minutes (182.04 days). 0 = cancel Geographic Notice; 1 – 262.142; 262.143 = undefined = default.
	Action		1	Action parameter: 0 = Advisement; 1 = Directive;
	Spare		2	not used, should be set to zero, reserved for future use.
	Sub-area 1		96	Area description, structured as in Table 3 - Table 8. A short text description may be associated with the areas using Sub-area 5: Associated text. 2-slot message.
	Sub-area 2		96	optional additional area, structured as in Table 3 - Table 8. 2-slot message.
	Sub-area 3		96	optional additional area, structured as in Table 3 - Table 8 2-slot message.
	Sub-area 4		96	optional additional area, structured as in Table 3 - Table 8 3-slot message.
	Sub-area 5		96	optional additional area, structured as in Table 3 - Table 8 3-slot message.
	Sub-area 6		96	optional additional area, structured as in Table 3 - Table 8 4-slot message.
	Sub-area 7		96	optional additional area, structured as in Table 3 - Table 8 4-slot message.
	Sub-area 8		96	optional additional area, structured as in Table 3 - Table 8 5-slot message.
	Sub-area 9		96	optional additional area, structured as in Table 3 - Table 8 5-slot message.
	Total		216-984	2-5 slot message

Number of sub-areas transmitted	1	2	3	4	5	6	7	8	9
Number of bits used for a broadcast message	216	312	408	504	600	696	792	888	984
Number of slots used for a broadcast message	2	2	3	3	3	4	4	5	5
Number of bits used for an addressed message	248	344	440	536	632	728	824	920	1016
Number of slots used for an addressed message	2	2	3	3	4	4	5	5	5

Table 1: Number of sub-area transmitted

Value	Area Shape	Table for Definition
0	Circle, point or accurate polyline/polygon	3
1	Rectangle	4
2	Sector	5
3	Polyline	6
4	Polygon	7
5	Associated text	8
6-7	Reserved	--

Table 2: Sub-areas

	Parameter	# of bits	Description
Geographic Notice: Sub-area shape 0	Area Shape	3	Defines the shape of the area. Set to 0 for Circle, or accurate polyline/polygon.
	Scale Factor	2	Scale factor. This is a multiplier for the dimensions of the shape. 1 (default), 10, 100, & 1,000 (scale factor = 10n where n=decimal value of scale factor). 0 = 1x (default), 1 = 10x; 2 = 100x, 3 = 1000x.
	Longitude	28	Longitude of the center in 1/10,000 minute (±180°). East = positive, West = negative (as per 2’s complement); 181° (6791AC0h[JvG2] [1] ) = not available = default.
	Latitude	27	Latitude of the center in 1/10,000 minute (±90°). North = positive, South = negative (as per 2’s complement); 91° (3412140h[JvG3] [2] ) = not available = default.
	Precision	3	Precision of the Lat/Long. Data to be truncated to the number of decimal places specified in this parameter. 0-4 decimal places. Default = 4 (no truncation). 5-6 = Reserved; 7 = Do not use.
	Radius	12	Defines the size of the circular area. This is the radius of the circle in meter increments. 0 = point (default); (scale factor should also be set to 0 in this case) 1 – 4,095m. This is multiplied by the scale factor to give a maximum size of 4.095m (4,095km).
	Link	2	Defines the possible link of the sub message[JvG4] [3] 0 = single point [J5] [4] / end point of polygon/polyline (default)[JvG6] [5] 1 = start/additional point of polyline 2 = start/additional point of polygone 3 = unused
	Spare	19	.not used, should be set to zero, reserved for future use
	Total	96	96 bit subarea

Table 3: Circle or Polygon Point

Figure 3: Circle diagram

points

Point	Link	Point	Link	Point	Link
1	0	1	1	1	2
2	0	2	1	2	2
3	0	3	2	3	2
4	0	4	0	4	0
5	0	5	1	5	2
6	0	6	1	6	2
7	0	7	1	7	2
8	0	8	0	8	0

Figure 4: coding of point, polylines and polygons using circle sub-areas

	Parameter	# of bits	Description
Geographic Notice: Sub-area shape 1	Area Shape	3	Defines the shape of the area. Set to 1 for Rectangle.
	Scale Factor	2	Scale factor. This is a multiplier for the dimensions of the shape. 1 (default), 10, 100, & 1,000 (scale factor = 10n where n=decimal value of scale factor). 0 = 1x (default), 1 = 10x; 2 = 100x, 3 = 1000x.
	Longitude	28	Longitude of the corner point*1 in 1/10,000 minute (±180°). East = positive, West = negative (as per 2’s complement); 181° (6791AC0h) [JvG1] [6] = not available = default.
	Latitude	27	Latitude of the corner point *1 in 1/10,000 minute (±90°). North = positive, South = negative (as per 2’s complement); 91° (3412140h) [JvG2] [1] = not available = default.
	Precision	3	Precision of the Lat/Long. Data to be truncated to the number of decimal places specified in this parameter. 0-4 decimal places. Default = 4 (no truncation). 5-6 = Reserved; 7 = Do not use.
	E dimension	8	Box dimension East from the corner point in meter increments. This is multiplied by the scale factor to give a maximum dimension of 255,000m (255 km). 0=line North-South (default); 1 – 255 * scale factor meters.
	N dimension	8	Box dimension North from the corner point in meter steps. This is multiplied by the scale factor to give a maximum dimension of 255,000m (255 km). 0=line East-West (default); 1 - 255 * scale factor meters.
	Orientation	9	Rotation of area in degree steps. Area is rotated clockwise this number of degrees about the position above. 0 = no rotation = default; 1 - 359 = rotation in degrees; 360 – 511 (reserved for future use).
	Spare	8	not used, should be set to zero, reserved for future use
	Total	96	96 bit subarea

Table 4: Rectangle or line or point

Figure 5: Rectangle diagram

	Parameter	# of bits	Description
Geographic Notice: Sub-area shape 2	Area Shape	3	Defines the shape of the area. Set to 2 for Sector.
	Scale Factor	2	Scale factor. This is a multiplier for the dimensions of the shape. 1 (default), 10, 100, & 1,000 (scale factor = 10n where n=decimal value of scale factor). 0 = 1x (default), 1 = 10x; 2 = 100x, 3 = 1000x.
	Longitude	28	Longitude of the center in 1/10,000 minute (±180°). East = positive, West = negative (as per 2’s complement); 181°= not available = default.
	Latitude	27	Latitude of the center in 1/10,000 minute (±90°). North = positive, South = negative (as per 2’s complement); 91° = not available = default.
	Precision	3	Precision of the Lat/Long. Data to be truncated to the number of decimal places specified in this parameter. 0-4 decimal places. Default = 4 (no truncation). 5-6 = Reserved; 7 = Do not use.
	Radius	12	Defines the size of the sector. This is the radius of the sector in meter increments. 1 – 4,095m. This is multiplied by the scale factor to give a maximum size of 4.095m (4,095km).
	Left boundary	9	Orientation of the left boundary edge of the sector. This is in degree steps measured clockwise from true North about the center point. 0 = no rotation = default; 1-359 = rotation in degrees; 360-511 (reserved for future use).
	Right boundary	9	Orientation of the right boundary edge of the sector. This is in degree steps measured clockwise from true North about the center point. Total sector area is the area measured from the left boundary clockwise to the right boundary. 0 = no rotation = default; 1-359 = rotation in degrees; 360-511 (reserved for future use)
	Spare	3	not used, should be set to zero, reserved for future use
	Total	96	96 bit subarea

Table 5: Sector

sector description

Figure 6: Sector description. a) Center point, b) Sector radius, c) Sector bearings from center point, left boundary, d) Sector bearings from center point, right boundary

	Parameter	# of bits	Description
Geographic Notice: Sub-area shape 3 (polyline) or 4 (polygon)	Area Shape	3	Defines the shape of the area. Set to 3 for Polyline (open area or line) or set to 4 for Polygon (closed area). The initial point (point 0) is defined by an Area Shape = 0 (Circle, point or accurate polyline/polygon). Or could be added to a previous Polyline/Polygon To close the polygon shape, connect the last defined point back to the initial point (Point 0).
	Scale Factor	2	Scale factor. This is a multiplier for the dimensions of the shape. 1 (default), 10, 100, & 1,000 (scale factor = 10n where n=decimal value of scale factor). 0 = 1x (default), 1 = 10x; 2 = 100x, 3 = 1000x.
	Point 1 Angle	10	True bearing (in half-degree steps) from Point 0 to Point 1 or from the last Point in a Polyline/Polygon directly preceding this Polyline/Polygon to Point 1 in this Polyline/Polygon. Degrees bearing = decimal value (0-719)/2; 720 = not available (no point) = default; 721 – 1,023 (not for use).
	Point 1 distance	11	Distance (in meters) from Point 0 or from the last Point in a Polyline/Polygon directly preceding this Polyline/Polygon to Point 1 in this Polyline/Polygon. Multiply by the scale factor to give a maximum of 2.047m (2,047 km). 0 = default (no point); 1- 2047 * scale factor meters.
	Point 2 Angle	10	True bearing (in half-degree steps) from Point 1 to Point 2 Degrees bearing = decimal value (0-719)/2; 720 = not available (no point) = default; 721 – 1,023 (not for use).
	Point 2 distance	11	Distance (in meters) from Point 1 to Point 2. Multiply by the scale factor to give a maximum of 2.047m (2,047 km). 0 = default (no point); 1- 2047 * scale factor meters.
	Point 3 Angle	10	True bearing (in half-degree steps) from Point 2 to Point 3 Degrees bearing = decimal value (0-719)/2; 720 = not available (no point) = default; 721 – 1,023 (not for use).
	Point 3 distance	11	Distance (in meters) from Point 2 to Point 3. Multiply by the scale factor to give a maximum of 2.047m (2,047 km). 0 = default (no point); 1- 2047 * scale factor meters.
	Point 4 Angle	10	True bearing (in half-degree steps) from Point 3 to Point 4 Degrees bearing = decimal value (0-719)/2; 720 = not available (no point) = default; 721 – 1,023 (not for use).
	Point 4 distance	11	Distance (in meters) from Point 3 to Point 4. Multiply by the scale factor to give a maximum of 2.047m (2,047 km). 0 = default (no point); 1- 2047 * scale factor meters.
	Link	2	Defines the possible link of the sub message 0 = single polyline/polygon and/or end point of polygon/polyline (default) 1 = start/additional point of polyline 2 = start/additional point of polygon 3 = unused
	Spare	5	not used, should be set to zero, reserved for future use
	Total	96	96 bit subarea

Table 6: Polyline

Examples of a single polyline (Area Shape = 3, Link = 0)

Graph desk

Figure 7: Graphic description of a waypoint/polyline, showing angle and distance between points. If one side of a polyline is to be a boundary (e.g., edge of ice area), this is defined by the left side of the line in order of sequence from the initial sub-area point (Point 0)

ice map

Figure 8: Graphic depiction of: 1) ice boundary between sea ice and open water, and 2) recommended route through the sea ice area

Storm area

Figure 9: A graphic depiction of a storm front message

	Parameter	# of bits	Description
Geographic Notice: Sub-area	Area Shape	3	Defines the shape of the area. Set to 5 for Associated Text. This text is associated with the area defined in this binary message. Multiple Associated Text sub-areas are glued together in the order they appear in the message.
	Text	90	Fifteen 6-bit ASCII characters, 6 bit ASCII characters as per Table 44 in ITU 1371-4. If less than 15 characters are required, then the remainder of the field should be filled with “@” characters (set bits to 0). On the ECS the @ characters at the end should not be displayed.
	Spare	3	not used, should be set to zero, reserved for future use
	Total	96	96 bit subarea

Table 8: Associated Text

Value	Description
0	Caution: Marine mammal habitat
1	Caution: Marine mammals in area - reduce speed
2	Caution: Marine mammals in area - stay clear
3	Caution: Marine mammals in area - report sightings
4	Caution: Protected Habitat - reduce speed
5	Caution: Protected habitat - stay clear
6	Caution: Protected habitat - no fishing or anchoring
7	Caution: Derelicts (drifting objects)
8	Caution: Traffic congestion
9	Caution: Marine event or regatta
10	Caution: Divers down
11	Caution: Swim area
12	Caution: Dredge operations
13	Caution: Survey operations
14	Caution: Underwater operation
15	Caution: Seaplane operations
16	Caution: Fishery - nets in water
17	Caution: Cluster of fishing vessels
18	Caution: Fairway closed
19	Caution: Harbor closed
20	Caution: Submerged pipeline or cable
21	Caution: Unmanned vehicle operation
22	Caution: other (define in associated text field)
23	Environmental Caution: Storm front (line squall)
24	Environmental Caution: Hazardous sea ice i.e. icebergs and growlers
25	Environmental Caution: Storm warning (storm cell or line of storms)
26	Environmental Caution: High wind
27	Environmental Caution: High waves
28	Environmental Caution: Restricted visibility (fog, rain, etc)
29	Environmental Caution: Strong currents
30	Environmental Caution: Heavy icing
31	Environmental Caution: Oil or other hazardous substance in area
32	Environmental Caution: other (define in associated text field)
33	Restriction: Fishing prohibited
34	Restriction: Entry approval required prior to transit
35	Restriction: Entry prohibited
36	Restriction: Active military OPAREA
37	Restriction: Firing - danger area
38	Restriction: Drifting mines
39	Restriction: other (define in associated text field)
40	Anchorage: Anchorage open
41	Anchorage: Anchorage closed
42	Anchorage: Anchoring prohibited
43	Anchorage: Deep draft anchorage
44	Anchorage: Shallow draft anchorage
45	Anchorage: Vessel transfer operations
46	Anchorage: other (define in associated text field)
47	Ice Report: Ice Edge
48	Ice Report: New Ice (<10cm ocean <5cm lake)
49	Ice Report: Young Ice (10-30cm)
50	Ice Report: Thin 1st year ice (30-70cm ocean, 5-15cm lake)
51	Ice Report: Medium 1st year ice (70-120cm ocean, 15-30cm lake)
52	Ice Report: Thick 1st year ice (120-200 cm ocean, 30-70cm lake)
53	Ice Report: Old /very thick ice (>200cm ocean, >70cm lake)
54	Ice Report: Undetermined or unknown thickness
55	Reserved for Future Use
56	Security Alert - Implement USA MARSEC Level 1
57	Security Alert - Implement USA MARSEC Level 2
58	Security Alert - Implement USA MARSEC Level 3
59	Reserved for Future Use
60	Reserved for Future Use
61	Reserved for Future Use
62	Reserved for Future Use
63	Reserved for Future Use
64	Distress: Vessel disabled and adrift
65	Distress: Vessel sinking
66	Distress: Vessel abandoning ship
67	Distress: Vessel requests medical assistance
68	Distress: Vessel flooding
69	Distress: Vessel fire/explosion
70	Distress: Vessel grounding
71	Distress: Vessel collision
72	Distress: Vessel listing/capsizing
73	Distress: Vessel under assault
74	Distress: Person overboard
75	Distress: SAR area
76	Distress: Pollution response area
77	Distress: other (define in associated text field)
78	Reserved for Future Use
79	Reserved for Future Use
80	Instruction: Contact VTS at this point/juncture
81	Instruction: Contact Port Administration at this point/juncture
82	Instruction: Do not proceed beyond this point/juncture
83	Instruction: Await instructions prior to proceeding beyond this point/juncture
84	Instruction: Proceed to this location – await instructions
85	Instruction: Clearance granted – proceed to berth/lock
86	Instruction: other (define in associated text field)
87	Reserved for Future Use
88	Information: Pilot boarding position
89	Information: Icebreaker waiting area
90	Information: Places of refuge
91	Information: Position of icebreakers
92	Information: Location of response units
93	Information: VTS active target
94	Information: Rogue or suspicious vessel
95	Information: Vessel requesting non-distress assistance
96	Information: other (define in associated text field)
97	Chart Feature: Submerged object / sunken vessel (describe in associated text field)
98	Chart Feature: Semi-submerged object
99	Chart Feature: Shoal area
100	Chart Feature: Shoal area due north
101	Chart Feature: Shoal area due east
102	Chart Feature: Shoal area due south
103	Chart Feature: Shoal area due west
104	Chart Feature: Channel obstruction
105	Chart Feature: Reduced vertical clearance
106	Chart Feature: Bridge/Gate/Lock/other closed
107	Chart Feature: Bridge/Gate/Lock/other partially open (opening)
108	Chart Feature: Bridge/Gate/Lock/other fully open
109	Chart Feature: Bridge/Gate/Lock/other partially closed (closing)
110	Chart Feature: Bridge/Gate/Lock/AtoN/other inoperative or not working properly
111	Chart Feature: other (define in associated text field)
112	Report from ship: Icing info
113	Report from ship: Intended route
114	Report from ship: other (define in associated text field)
115	Reserved for Future Use
116	Reserved for Future Use
117	Reserved for Future Use
118	Reserved for Future Use
119	Reserved for Future Use
120	Route: Recommended Route
121	Route: Alternative Route
122	Route: Recommended Route through ice
123	Route: other (define in associated text field)
124	Reserved for Future Use
125	Other – Define in associated text field
126	Cancellation – cancel area as identified by Message Linkage ID
127	Undefined (default)

Table 9: Notice Description