|
Saint Lawrence Seaway and PAWSS AIS Messages
3 Wind Information Message
| Parameter |
Number of bits |
Description |
| Application ID |
16 |
DAC = 316 or 366; FI = 1; See Section 2.1 |
| Reserved |
2 |
|
| Message ID |
6 |
Message Identifier = 2 (00 0010 in binary) |
| Binary Data |
Max 864 |
From 1 up to 6 wind information reports, each structured as
defined in Section 3.1 |
| Total Number of bits |
Max 888 |
= 24 + N*144
N Total Bits (Slots Required)
1 168 bits (2 slots)
2 312 bits (2 slots)
3 456 bits (3 slots)
4 600 bits (4 slots)
5 744 bits (4 slots)
6 888 bits (5 slots) |
|
3.1 Wind Information Report
| Parameter |
Number of bits |
Description |
| Timetag |
20 |
Month, Day and Time of measurement, See Section 2.2 |
| Station ID |
42 |
Seven 6-bit ASCII character ID |
| Longitude |
25 |
Longitude in 1/1000 minute (±180 degrees, East = positive,
West = negative 181 degrees = not available) |
| Latitude |
24 |
Latitude in 1/1000 minute (±90 degrees, North = positive,
South = negative. 91 degrees = not available) |
| Wind Speed |
10 |
Average Wind Speed in 1/10th Knot (0-102.2 knots, 1022 = 102.2
kts or greater, 1023 = not available) |
| Wind Gust |
10 |
Wind Gust in 1/10th Knot (0-102.2 knots, 1022 = 102.2 kts
or greater, 1023 = not available) |
| Wind Direction |
9 |
Quantized to 16 compass points (Seaway only); See Section
3.1.1 |
| Reserved |
4 |
Reserved for future use |
| Total Number of bits |
144 |
|
|
Notes:
Wind information is gathered from anemometers at various
Seaway facilities; this information is updated every 15 minutes.
The wind speed is derived from averaging the instantaneous
readings over a 15-minute interval.
Wind gust represents the highest wind speed measured
over 15 minutes.
Each wind information message may contain up to six
station readings. If there are more than six station readings, additional messages
shall be generated.
Wind information from all sensors is transmitted to
users throughout the entire Saint Lawrence Seaway AIS network.
3.1.1 Wind Direction Quantization
Wind direction will be quantized to represent 16 compass
points for Saint Lawrence Seaway Stations.
| Parameter |
Number of bits |
Description |
| Direction |
9 |
Direction, 0-359 degrees, 511 = not available For Saint Lawrence
Seaway, refer to table below for descriptions of quantized values. |
| Total Number of bits |
9 |
|
|
| Direction Value |
Description |
| 0 |
N |
| 23 |
NNE |
| 45 |
NE |
| 68 |
ENE |
| 90 |
E |
| 113 |
ESE |
| 135 |
SE |
| 158 |
SSE |
| 180 |
S |
| 203 |
SSW |
| 225 |
SW |
| 248 |
WSW |
| 270 |
W |
| 293 |
WNW |
| 315 |
NW |
| 338 |
NNW |
|
3.2 Example: Wind Information Message
| Designated Area Code |
Function Id |
Res. |
Message Id |
| 0 |
1 |
0 |
0 |
1 |
1 |
1 |
1 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
| 316 |
1 |
0 |
2 |
|
| Timetag |
・・・ |
| 0 |
1 |
0 |
1 |
1 |
1 |
1 |
0 |
1 |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
0 |
1 |
0 |
0 |
1 |
0 |
1 |
| 5 |
29 |
00 |
34 |
"T"・・・ |
|
| ・・・Station Id・・・ |
| 0 |
0 |
0 |
0 |
0 |
1 |
0 |
1 |
0 |
1 |
0 |
0 |
1 |
1 |
0 |
1 |
0 |
1 |
0 |
0 |
1 |
1 |
0 |
0 |
| ・・・"T" |
"E" |
"S" |
"T" |
"1"・・・ |
|
| ・・・Station Id... |
Longitude・・・ |
| 0 |
1 |
1 |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
1 |
1 |
0 |
0 |
0 |
1 |
| ・・・"1" |
"" |
"" |
27°05' E・・・ |
|
| ・・・Longitude |
Latitude・・・ |
| 1 |
0 |
0 |
1 |
0 |
1 |
1 |
1 |
0 |
1 |
0 |
1 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
1 |
| ・・・27°05' E |
5°05' N・・・ |
|
| ・・・Latitude |
Wind Speed・・・ |
| 0 |
1 |
0 |
0 |
1 |
1 |
1 |
0 |
1 |
1 |
0 |
1 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
0 |
0 |
| ・・・5°05' N |
3.2 Knots |
|
| ・・・ |
Wind Gust |
Wind Direction |
Reserved |
| 0 |
0 |
0 |
0 |
0 |
1 |
0 |
1 |
0 |
0 |
0 |
1 |
0 |
0 |
1 |
0 |
0 |
1 |
0 |
1 |
0 |
0 |
0 |
0 |
| ・・・ |
4.0 Knots |
293 Degrees |
0 |
|
4 Weather Station Message
| Parameter |
Number of bits |
Description |
| Application ID |
16 |
DAC = 316 or 366; FI = 1; See Section 2.1 |
| Reserved |
2 |
|
| Message ID |
6 |
Message Identifier = 1 (00 0001 in binary) |
| Binary Data |
Max 768 |
Message contains 1 to 4 weather station reports, each structured
defined in Section 4.1 |
| Total Number of bits |
Max 792 |
= 24 + N*192
N Total Bits (Slots Required)
1 216 bits (2 slots)
2 408 bits (3 slots)
3 600 bits (4 slots)
4 792 bits (5 slots) |
|
4.1 Weather Station Report
| Timetag |
20 |
Month, Day and Time of measurement, See Section 2.2 |
| Station ID |
42 |
Seven 6-bit ASCII character ID |
| Longitude |
25 |
Longitude in 1/1000 minute (±180 degrees, East = positive,
West = negative. 181 = not available) |
| Latitude |
24 |
Latitude in 1/1000 minute (±90 degrees, North = positive,
South = negative. 91 = not available) |
| Wind Speed |
10 |
Speed in 1/10th Knot; 0-102.2 knots, 1022 = 102.2 kts or greater,
1023 = not available |
| Wind Gust |
10 |
Gust in 1/10th Knot; 0-102.2 knots, 1022 = 102.2 kts or greater,
1023 = not available |
| Wind Direction |
9 |
Direction in degrees; 0-359 degrees, 511=NA |
| Atmospheric Pressure |
14 |
Expressed in 1/10th millibars. (16383 = not available) |
| Air Temp |
10 |
Temperature in 1/10th of a degree Celsius (signed) (-511 to
511 valid range, -511 = -51.1℃ or less, 511 = 51.1℃ or greater, -512 = not available) |
| Dew Point |
10 |
Temperature in 1/10th of a degree Celsius (signed) (-511 to
511 valid range, -511 = -51.1℃ or less, 511 = 51.1℃ or greater, -512 = not available) |
| Visibility |
8 |
Visibility in 1/10 kilometers. (0-254, 254 = 25.4km or greater,
255 = not available) |
| Water Temp |
10 |
Temperature in 1/10th of a degree Celsius (signed) (-511 to
511 valid range, -511 = -51.1℃ or less, 511 = 51.1℃ or greater, -512 = not available) |
| Total Number of bits |
192 |
|
|
Notes:
The Weather Station Reports are station observations
from the National Data Buoy Center (NDBC). Typically, the information is updated
once every hour. Depending on climatic conditions, traffic controllers at the
Massena, New York Vessel Traffic Control Center may provide weather condition
updates at a more frequent update interval.
The Seaway AIS network will broadcast the following
NDBC stations for the Saint Lawrence River:
・Superior Shoals, NY Station Identifier: SUPN6
・Thousand island Bridge. NY Station Identifier: THIN6
・Alexandria Bay, NY Station Identifier: ABAN6
Please refer to the National Data Buoy Center web site
at the following address for additional information.
The Weather Station Messages are transmitted to users
throughout the entire Saint Lawrence Seaway AIS network.
4.2 Example: Weather Station Message
| Designated Area Code |
Function Id |
Res. |
Message Id |
| 0 |
1 |
0 |
0 |
1 |
1 |
1 |
1 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
1 |
| 316 |
1 |
0 |
1 |
|
| Timetag |
・・・ |
| 0 |
1 |
0 |
1 |
1 |
1 |
1 |
0 |
1 |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
0 |
1 |
0 |
0 |
1 |
0 |
1 |
| 5 |
29 |
00 |
34 |
"T"・・・ |
|
| ・・・Station Id・・・ |
| 0 |
0 |
0 |
0 |
0 |
1 |
0 |
1 |
0 |
1 |
0 |
0 |
1 |
1 |
0 |
1 |
0 |
1 |
0 |
0 |
1 |
1 |
0 |
0 |
| ・・・"T" |
"E" |
"S" |
"T" |
"1"・・・ |
|
| ・・・Station Id |
Longitude・・・ |
| 0 |
1 |
1 |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
1 |
1 |
0 |
0 |
0 |
1 |
| ・・・"1" |
"" |
"" |
27°05' E・・・ |
|
| ・・・Longitude |
Latitude・・・ |
| 1 |
0 |
0 |
1 |
0 |
1 |
1 |
1 |
0 |
1 |
0 |
1 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
1 |
| ・・・27°05' E |
5°05' N・・・ |
|
| ・・・Latitude |
Wind Speed・・・ |
| 0 |
1 |
0 |
0 |
1 |
1 |
1 |
0 |
1 |
1 |
0 |
1 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
0 |
0 |
| ・・・5°05' N |
3.2 Knots |
|
| ・・・ |
Wind Gust |
Wind Direction |
・・・ |
| 0 |
0 |
0 |
0 |
0 |
1 |
0 |
1 |
0 |
0 |
0 |
1 |
0 |
0 |
1 |
0 |
0 |
1 |
0 |
1 |
1 |
0 |
0 |
1 |
| ・・・ |
4.0 Knots |
293 Degrees |
・・・ |
|
| ・・・Atmospheric Pressure |
Air Temp |
Dew Point・・・ |
| 1 |
1 |
0 |
0 |
0 |
1 |
0 |
0 |
0 |
0 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
0 |
1 |
1 |
1 |
1 |
| 1000 millibars |
-0.2℃ |
・・・ |
|
| ・・・Dew point |
Visibility |
Water Temp |
| 1 |
1 |
0 |
1 |
0 |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
1 |
0 |
0 |
0 |
0 |
1 |
1 |
1 |
1 |
0 |
0 |
| ・・・-1.2℃ |
0.9 Km |
6.0℃ |
|
|
