IALA

Environmental

Introduction/Additional information:

12.1 This message provides environmental information from 1 to 8 sensor reports (e.g., 1 sensor report uses 2 slots while a message with 8 sensor reports can use up to 5 slots). Each sensor report carries the dynamic or static information relating to a specific sensor.

12.2 Each Environmental Message has 56 bits of standard header, with 12 bits available for payload. Each sensor report has 27 bits of common data leaving 85 bits for sensor data. Table 12.3 provides the framework for the sensor report.

12.2.1 Table 12.4 outlines a variety of sensor types that can be transmitted using this message.

12.2.2 The sensor data is defined in accordance to the sensor type. Tables 12.5 to 12.15 provide details for the 85 bits of information for each sensor report type. In each case “Sensor not available” means that the specific reading is not ever possible from that sensor location and “Data not available” means that the reading is possible but is not available for the current report (i.e. the sensor could be malfunctioning).

 

Registrant:
IMO Circ. 289
Message number:
8
DAC:
1
FI:
26
State:
in force
Number of slots (max):
5
Permitted as from:
01/06/2010
Details:

Table 12.1

Environmental

 

Parameter No of bits Description
Standard Message Header Message ID 6 Identifier for Message 8; Set to 8 (broadcast, no acknowledgement).
Repeat Indicator 2 Used by the repeater to indicate how many times a message has been repeated (see ITU-R M.1317, Annex 2, § 4.6.1).

0 – 3

0 = default

3 = do not repeat any more

Set to 0 (default).

Source MMSI 30 MMSI number of source station. Varies according to the transmitter ID.
Spare 2 Not used. Set to zero.
Binary Data Designated Area Code 10  DAC = 001
Function Identifier 6  FI = 26
Application Data Max 952 From 1 to 8 sensor reports, each structured as in Table 12.3. The total number of reports is determined by the receiver based on the length of the data.
Total Max 1,008 Occupies 2-5 slots. (See Table 12.2)

 

 

Table 12.2

Number of slots

 

Number of bits used 168 280 392 504 616 728 840 952
Number of slots required

(168 bits in first 210 in 2-5)

1 2

(max 378)

3

(max 588)

3 4

(max 798)

4 5

(max 1,008)

5

 

 

Table 12.3

Environmental message – Sensor report framework

 

Parameter No of bits Description
Report Type 4 Environmental Report Type as defined in Table 12.4
Time Stamp   UTC date and time.
UTC Day 5 1 – 31

0 = not available = default

UTC Hour 5 0 – 23

24 = not available = default

UTC Minute 6 0 – 59

60 = not available = default

Site ID 7 Binary identifier of sensor site, combined with transmitter MMSI to fully identify sensor site (i.e., there can be more than one physical sensors, each one reporting different data types at a sensor site)
Sensor Data 85 Sensor data according to the sensor type (see Tables 12.5 – 12.15)
Total  112  

 

Table 12.4

Environmental Message Sensor Report Types

 

Value Description
0 Site Location
1 Station ID
2 Wind
3 Water level
4 Current Flow (2D)
5 Current Flow (3D)
6 Horizontal Current Flow
7 Sea State
8 Salinity
9 Weather
10 Air gap / Air draft
11-15 (reserved for future use)

 

Table 12.5

 Site location report

 

Parameter No of bits Description
Longitude 28 Longitude in 1/10,000 min, ±180 degrees as per 2’s complement (East = positive, West = negative).

181 = not available = default

Latitude 27 Latitude in 1/10,000 min, ±90 degrees as per 2’s complement (North = positive, South = negative).

91 degrees = not available = default

Altitude 11 Altitude of the sensor relative to MSL, in 0.1 metre steps.

0.0 – 200 metres

2,001 = altitude 201 metres or greater

2,002 = not available = default

2,003 – 2,046  (reserved for future use)

Sensor Owner 4 Owner of the sensor/responsible for the sensor data.

0 =  unknown = default

1 = hydrographic office

2 = inland waterway authority

3 = coastal directorate

4 = meteorological service

5 = port authority

6 = coast guard

7 – 13 (reserved for future use[GWJ1] )

14 (reserved for regional use)

Data Timeout 3 Length of time that data is valid (i.e., should not be used after timeout period).

0 = no timeout period = default

1 = 10 min

2 = 1 hr

3 = 6 hrs

4 = 12 hrs

5 = 24 hrs

6 – 7  (reserved for future use)

Spare 12 Not used. Set to zero
Total 85  

 

 

Table 12.6

Station ID Report

 

Parameter No of bits Description
Name 84 Agency reference number. Fourteen characters 6-bits ASCII  as defined in ITU-R M.1371-3, Table 44.
Spare 1 Not used. Set to zero.
Total 85  

 

 

Table 12.7

Wind Report

 

Parameter No of bits Description
Average Wind Speed 7 Average of wind speed values over the last 10 minutes, in 1 knot steps.

0 – 120 knots

121 = wind 121 knots greater

122 = not available = default

123 – 126  (reserved for future use)

Wind Gust 7 Max wind speed reading during the last 10 minutes, in 1 knot steps.

0 – 120 knots

121 = wind 121 knots or greater

122 = not available = default

123 – 126  (reserved for future use)

Wind Direction 9 Direction of the average wind over the last 10 minutes, in 1 degree steps.

0 – 359 degrees

360 = not available = default

361 – 511 (not for use)

Wind Gust Direction 9 Direction of the maximum wind over the last 10 minutes, in 1 degree steps.

0 – 359 degrees

360 = not available = default

361-511 (not for use)

Sensor Data Description 3 Type of data from Wind sensor, as defined in Table 12.16.
Forecast Wind Speed 7 Predicted average wind speed, in 1 knot steps.

0 – 120 knots

121 = wind 121 knots or greater

122 = not available = default

123 – 126 (reserved for future use)

Forecast Wind Gust 7 Predicted maximum wind speed, in 1 knot steps.

0 – 120 knots

121 = wind 121 knots or greater

122 = not available = default

123 – 126  (reserved for future use)

Forecast Wind Direction 9 Predicted direction of the average wind, in 1 degree steps.

0 – 359 degrees

360 = not available = default

361-511 (not for use)

Valid Time of Forecast   Valid UTC date and time of forecast.
UTC Day 5 1 – 31

0 = not available = default

UTC Hour 5 0 – 23

24 = not available = default

UTC Minute 6 0 – 59

60 = not available = default

Duration 8 Duration of the validity of the forecast from the time of the forecast, in 1 minute steps.

1 – 255 minutes

0 = cancel forecast = default

Spare 3 Not used. Set to zero.
Total 85  

 

Table 12.8

Water level report

 

Parameter No of bits Description
Water Level Type 1 Type of water level.

0 = relative to reference datum

1 = water depth

Water Level 16 Water level, in 0.1 metre steps (as per 2’s complement).

-327.67 to +327.67 metres

-32767 = -327.67 metres or less

+32767 = +327.67 metres or greater

-32768 = not available = default

Water Level Trend 2 0 = increasing

1 = decreasing

2 = steady

3 = not available = default

Vertical Reference Datum 5 Type of datum used.

0 = Mean Lower Low Water (MLLW)

1 = International Great Lakes Datum (IGLD-85)

2 = Local river datum

3 = Station Datum (STND)

4 = Mean Higher High Water (MHHW)

5 = Mean High Water (MHW)

6 = Mean Sea Level (MSL)

7 = Mean Low Water (MLW)

8 = National Geodetic Vertical Datum (NGVD-29)

9 = North American Vertical Datum (NAVD-88)

10 = World Geodetic System (WGS-84)

11 = Lowest Astronomical Tide (LAT)

12 = pool

13 = gauge

14 =  unknown/not available = default

15 – 30 (reserved for future use)

Sensor Data Description 3 Type of data from Water Level sensor, as defined in Table 12.16.
Forecast Water Level Type 1 Type of water level for forecast

0 = relative to reference datum

1 = water depth

Forecast Water Level 16 Forecast water level, in 0.1 metre steps (as per 2’s complement).

-327.67 to +327.67 metres

-32767 = -327.67 metres or less

+32767 = +327.67 metres or greater

-32768 = not available = default

Valid Time of Forecast   Valid UTC date and time of Forecast.
UTC Day 5 1 – 31

0 = not available = default

UTC Hour 5 0 – 23

24 = not available = default

UTC Minute 6 0 – 59

60 = not available = default

Duration 8 Duration of the validity of the forecast from the time of the forecast, in 1 minute steps.

1 – 255 minutes

0 = cancel forecast = default

Spare 17 Not used. Set to zero.
Total No. bits 85  

Table 12.9

Current Flow Report: two-dimensions (x & y)

 

Parameter No of bits Description
Current Speed 1 8 Speed of Current 1 measured at a chosen level below the sea surface, in 0.1 knot steps.

0.0 – 24.5 knots

246 = speed 24.6 knots or greater

247 = data not available = default

248 – 255  (reserved for future use)

Current Direction 1 9 Direction of Current 1, in 1 degree steps.

0 – 359 degrees

360 = not available = default

361-511 (reserved for future use)

Current Measuring level 1 9 Measurement level of Current 1 below sea surface, in 1 metre steps.

0 – 360 metres

361 = 361 m or greater

362 = not available = default

363 – 511 (reserved for future use)

Current Speed 2 8 Speed of Current 2 measured at a chosen level below the sea surface, in 0.1 knot steps.

(Same as Current Speed 1)

Current Direction 2 9 Direction of Current 2, in 1 degree steps.

(Same as Current Direction 1)

Current Measuring level 2 9 Measurement level of Current 2 below sea surface, in 1 metre steps.

(Same as Current Measuring level 1)

Current Speed 3 8 Speed of Current 3 measured at a chosen level below the sea surface, in 0.1 knot steps.

(Same as Current Speed 1)

Current Direction 3 9 Direction of Current 3, in 1 degree steps.

(Same as Current Direction 1)

Current Measuring level 3 9 Measurement level of Current 3 below sea surface, in 1 metre steps.

(Same as Current Measuring level 1)

Sensor Data Description 3 Type of data from current sensor, as defined in Table 12.16.
Spare 4 Not used. Set to zero.
Total 85  

 

 

Table 12.10

Current flow Report: 3-dimensions (x, y, & z)

 

Parameter No of bits Description
Current Vector Component North (u) 1 8 Speed of North component of Current 1 measured at a chosen level below the sea surface, in 0.1 knot steps.

0.0 – 24.5 knots

246 = speed 24.6 knots or greater

247 = not available = default

248 – 254  (reserved for future use)

Current Vector Component East (v) 1 8 Speed of East component of Current 1 measured at a chosen level below the sea surface, in 0.1 knot steps.

0.0 – 24.5 knots

246 = speed 24.6 knots or greater

247 = not available = default

248 – 254  (reserved for future use)

Current Vector Component Up (z) 1 8 Speed of Up component of Current 1 measured at a chosen level below the sea surface, in 0.1 knot steps.

0.0 – 24.5 knots

246 = speed 24.6 knots or greater

247 = not available = default

248 – 254 (reserved for future use)

Current Measuring level 1 9 Measurement level of Current 1 below sea surface, in 1 metre steps.

0 – 360 metres

361 = not available = default

362 – 511 (reserved for future use)[GWJ2]

Current Vector Component North (u) 2 8 Speed of North component of Current 2 measured at a chosen level below the sea surface, in 0.1 knot steps.

(Same as for Current 1)

Current Vector Component East (v) 2 8 Speed of East component of Current 2 measured at a chosen level below the sea surface, in 0.1 knot steps.

(Same as for Current 1)

Current Vector Component Up (z) 2 8 Speed of Up component of Current 2 measured at a chosen level below the sea surface, in 0.1 knot steps.

(Same as for Current 1)

Current Measuring level 2 9 Measurement level of Current 2 below sea surface, in 1 metre steps.

(Same as for Current 1)

Sensor Data Description 3 Type of data from Current sensor, as defined in Table 12.16.
Spare 16 Not used. Set to zero.
Total 85  

 

Table 12.11

Horizontal current flow report

 

Parameter No of bits Description
Current Reading 1 Bearing 9 Bearing of Current 1 reading from sensor position, in 1 degree steps.

0 – 359 degrees

360 = data not available = default

361 = sensor not available

362 – 511 (reserved for future use)

Current Reading 1 Distance 7 Distance of Current 1 reading from sensor position, in 1 metre steps[GWJ3] .

0 – 120 metres

121 = 121 m or greater

122 = not available = default

123 – 127 (reserved for future use)

Current 1 Speed 8 Speed of Current 1 measured at a chosen level below the sea surface, in 0.1 knot steps.

0.0 – 24.5 knots

246 = speed 24.6 knots or greater

247 = not available = default

248 – 255 (reserved for future use)

Current 1 Direction 9 Direction of Current 1, in 1 degree steps.

0 – 359 degrees

360 = data not available = default

361-511 (not for use)

Current 1 Measuring level 9 Measurement level of Current 1 below sea surface, in 1 metre steps.

0 – 360 metres

361 = level 361 metres or greater

362 = data not available = default

363 – 511  (reserved for future use)

Current Reading 2 Bearing 9 Bearing of Current 2 reading from sensor position, 1 degree steps.

(Same as for Current 1 bearing)

Current Reading 2 Distance 7 Distance of Current 2 reading from sensor position, 1metre steps[GWJ4] .

(Same as for Current 1 Distance)

Current 2 Speed 8 Speed of Current 2 measured at a chosen level below the sea surface, in 0.1 knot steps.

(Same as for Current 1 Speed)

Current 2 Direction 9 Direction of Current 2, in 1 degree steps.

(Same as for Current 1 Direction)

Current 2 Measuring level 9 Measurement level of Current 1 below sea surface, in 1 metre steps.

(Same as for Current 1 level)

Spare 1 Not used. Set to zero.
Total 85  

 

Table 12.12

Sea state report

 

Parameter No of bits Description
Swell Height 8 Height of the swell, in 0.1 metre steps.

0.0 – 24.5 metres

246 = height 24.6 metres or greater

247 = not available = default

248 – 255 (reserved for future use)

Swell Period 6 Swell period in seconds, in 1seccond steps.

0 – 60 seconds

61 = not available = default

62 – 63 (reserved for future use)

Swell Direction 9 Direction of swells, in 1 degree steps.

0 – 359 degrees

360 = not available = default

361-511 (reserved for future use)

Sea State 4 Beaufort Scale, as defined in Table 1.2
Sensor Data Description 3 Type of data from Swell sensor, as defined in Table 12.16
Water Temperature 10 Temperature of the water in degrees Celsius (as per 2’s complement), in 0.1 degree steps.

-10.0 to + 50.0 degrees Celsius

temp = decimal value /10 – 10 for decimal = 0 – 600

601 = not available = default

602 – 1,023 (reserved for future use)

Water Temperature Depth 7 Depth of water temperature sensor, in 0.1 metre steps.

0 – 12.0 metres

121 = depth 12.1 metres or greater

122 = not available = default

123 – 126  (reserved for future use)

Sensor Data Description 3 Type of data from Water Temperature sensor, as defined in Table 12.16.
Significant Wave Height 8 Height of the waves, in 0.1 metre steps.

0.0 – 24.5 metres

246 = height 24.6 m or greater

247 = not available = default

248 – 255  (reserved for future use)

Wave Period 6 Wave period, in 1 second steps.

0 – 60 seconds

61 = not available = default

62- 63 (reserved for future use)

Wave Direction 9 Direction of waves, in 1 degree steps.

0 – 359 degrees

360 = not available = default

361 – 511 (reserved for future use)

Sensor Data Description 3 Type of data from Wave sensor, as defined in Table 12.16.
Salinity 9 Salinity in 0.1‰ (ppt) steps.

0.0 – 50.0‰

501 = salinity 50.1‰ or greater

502 = data not available = default

503 = sensor not available

504 – 511  (reserved for future use)

Total 85  

 

Table 12.13

Salinity report

 

Parameter No of bits Description
Water Temperature 10 Temperature of water in degrees Celsius, in 0.1 degree steps.

-10.0 to + 50.0 degrees

temp = decimal value /10 – 10 for decimal = 0 – 600

601 = data not available

602 = sensor not available = default

603 – 1,023 (reserved for future use)

Conductivity 10 Water conductivity in Siemens/metre, in 0.01 S/m steps.

0.0 – 7.00 Siemens/metre

7.01 = conductivity 7.01 or greater

702 = data not available

703 = sensor not available = default,

704 – 1,023 (reserved for future use)

Water Pressure 16 Pressure of water in decibars, in 0.1 decibars steps.

0.0 to 6000.0 decibars

6000.1 = pressure 6000.1 or greater

60002 = data not available

60003 = sensor not available = default

60004 – 65535 (reserved for future use)

Salinity 9 Salinity in 0.1‰ (ppt) steps.

0.0 – 50.0 ‰

50.1 = salinity 50.1 or greater

502 = data not available = default

503 = sensor not available

504 – 511  (reserved for future use)

Salinity Type 2 Type of salinity.

0 = measured

1 = calculated using PSS-78

2 = calculated using other method

3 (reserved for future use)

Sensor Data Description 3 Type of data from Salinity sensor, as defined in Table 12.16.
Spare 35 Not used. Set to zero.
Total 85  

Table 12.14

Weather report

 

Parameter No of bits Description
Air Temperature 11 Dry bulb temperature in degrees Celsius (as per 2’s complement), in 0.1 degree steps.

-60.0 to +60.0 degrees Celsius

-1,024 = data unavailable = default

-1,023 to -601 (reserved for future use)

601 – 1,023 (reserved for future use)

Sensor Data Description 3 Type of data from Air Temperature sensor, as defined in Table 12.16.
Precipitation (type) 2 According to WMO

0 = rain

1 = snow

2 = rain and snow

3 = other

Horizontal Visibility 8 Visibility in Nautical Miles, in 0.1 NM steps.

0.0 – 24.0 NM

241 = visibility 24.1 NM or greater

242 = data not available

243 = sensor not available = default

244 – 255  (reserved for future use)

Dew Point 10 Dew point temperature in degrees Celsius (as per 2’s complement), in 0.1 degree steps.

-20.0 to +50.0 degrees Celsius

 

501 = not available = default

502-511 (reserved for future use)

-511 to -201(reserved for future use)

Sensor Data Description 3 Type of data from Dew Point sensor, as defined in Table 12.16.
Air Pressure 9 Air pressure, defined as pressure reduced to sea level, in 1 hPa steps.

0 = pressure 800 hPa or less

1 – 401 = 800 – 1200 hPa

402 = pressure 1201 hPa or greater

403  = data not available = default

404 – 511 (reserved for future use)

Air Pressure Trend 2 Air pressure trend

0 = steady

1 = decreasing

2 = increasing

3 = undefined = default

Sensor Data Description 3 Type of data from air pressure sensor, as defined in Table 12.16.
Salinity 9 Salinity in 0.1‰ (ppt) steps.

0.0 – 50.0 ‰

501 = salinity 50.1 or greater

511 = data not available = default

512 = sensor not available

503 – 511 (reserved for future use)

Spare 25 Not used. Set to zero.
Total 85  

 

 

Table 12.15

Air gap / Air draught

 

Parameter No of bits Description
Air Draught

 

13 Vertical distance measured from the ship’s waterline to the highest point on the ship, in 0.1 metre steps.

1 – 81.90 metres

8,191 = distance 81.91 metres or greater

0 = data not available = default

Air Gap 13 Vertical distance measured from the surface of the water to the sensor, in 0.1 metre steps.

1 – 81.9 metres

8,191 = distance 81.91 metres or greater

0 = data not available = default

Air Gap Trend 2 Trend of the air gap measurement.

0 = steady

1 = rising

2 = falling

3 = no data = default

Forecast Air Gap 13 The forecast vertical distance measured from the surface of the water to the sensor, in 0.01 metre steps. This is the measurement for the time of the forecast.

1 – 81.90 metres

8,191 = distance 81.91 metres or greater

0 = data not available = default

Valid Time of the Forecast   Valid UTC date and time of the forecast.
UTC Day 5 1 – 31

0 = not available = default

UTC Hour 5 0 – 23

24 = not available = default

25 – 31  (reserved for future use)

UTC Minute 6 0 – 59

60 = not available = default

61 – 63   (reserved for future use)

Spare 28 Not used. Set to zero.
Total 85  

 

 

Table 12.16

Type of data from sensor

 

Value Description
0 no data = default
1 raw real time
2 real time with Quality Control
3 predicted (based historical statistics)
4 forecast (predicted, refined with real-time information)
5 Nowcast (a continuous forecast)
6 (reserved for future use)
7 sensor not available