APRS version 1.2.1 WEATHER UPDATES TO THE SPEC 24 Mar 2011 ------------------------------------------------------------------- 24 Mar 2011 Proposed major simplification of new sensor approach 23 Mar 2011 updated Radiation Reporting Field 6 Jan 2010 previous version After the Japanese Nuclear incident in Mar 2011, we realized we needed a radiation sensor field in the APRS weather format. But in 2006 we had already added Flood gages and Flooding symbols. Apparently on Firenet where these water gage symbols appear, they are all not using the weather format but are using this format: ;09428508 *061713z3401.40N/11424.75Ww3.57gh/82cfs This March 2011 we have proposed a change to simplify new sensors as follows: 1) All weather data (and any new sensor data) will be transmitted using one of the existing WX parsable symbols: *_, where "*" is now used as a wildcard meaning any of the table characters or overlays. 2) All HAZARD symbol categories will also be parsed for weather and other sensor formatted data. This is because, once a condition has exceeded a threshold, that station/sensor can change its symbol to indicate that HAZARDOUS condition. So this includes *H symbols. 3) The 2006 Water gage format noted above will not change, since it has no impact on the weather sensor format. The 2006 proposal for water gages did include a format for inclusion in weather data, and that format is still valid, but will ONLY be parsed for in otherwise valid weather data formats. The special water gage and flooding symbols /w and \w introduced in 2006 will not be parsed for weather data as originally proposed. Changes implicated by the above will be updated in all APRS files that I can find. Such as: http://aprs.org/aprs11/symbols.txt http://aprs.org/aprs12/watergage.txt Readers should also review all the clarifications to the original spec made in the APRS1.1 addendum in this document: http://aprs.org/aprs11/spec-wx.txt This new aprs12/weather-new.txt file will contain all proposed APRS1.2 additions to the WX format fields. For the full APRS1.2 addendum, see http://aprs.org/aprs12.html COMPLETE REPORT: The use of the COMPLETE APRS weather format is strongly encouraged where both position and weather data are included in a single COMPLETE packet. The use of the positionless weather format is strongly discouraged since it is useless without position, and the requirement for additional weather station position report packets are equally useless without weather included in them! It is an anathma for a real time system such as APRS to split this data among multiple unreliable packets. RADIATION LEVEL: The field Xxxx has been proposed for reporting the level of Nuclear Radiation levels if available. The X is the type indicator. We chose "X" for radiation. The xxx are like the resistor code. First, two digits of precision and the last digit is the order of magnitude in NANOSEVERTS/Hr. So 123 is 12 * 10^3 nanosieverts/hr or 12 microsieverts/hr. Or 456 is 45 * 10^6 nanosieverts/hr or 45 millisieverts/hr. One bananna generates about .1 uSieverts/hr, a Brazil nut .4 uS/hr. If the radiation is at background levels the /_ weather symbol may be used, when elevated readings occur, the R_ weather symbol with "R" overlay will indicate a Radiation Sensor weather station. When a hazard threshold has been reached, the symbol can change to a RH symbol (Hazard with R overlay). WATER GAUGE INFO: In June 06, water level gage info was added to APRS. Two new symbols were introduced, one for H2O "/w" and the other for FLOOD "\w". The device can choose to send either of these symbols depending on its own threshold for "flooding". The data format for these objects appears to be: ;09428508 *061713z3401.40N/11424.75Ww3.57gh/82cfs Which is standard Object format with a text of "3.57gh/82cfs" meaning gage height and cubic feet per second. NEW: We propose that water gage readings can also be included in weather reports. For benign water readings included with WX info use the normal /_ weather symbol, unless the flood gage reading is important when the F_ weather station with F overlay will be used. When FLOOD conditions are reached, the symbol can change to a hazard symbol (FH). The height above or below flood or tide level in inches is included in the position comment string as Fxxxx and that string is chosen to be compatible with the standard APRS weather reporting parameters. In addition, a voltage field Vvvv is also added. Thus, the usual APRS weather report string similar to: DIR/SPD/Gggg/Tttt/Rrrr/Pppp etc is extended by adding these additional parameters for Fxxxx water level above or below flood stage or mean tide in tenths of a foot. Values can range between +999 and -999 in tenths meaning -99.9 to +99.9 feet. Meters are not used for the on air format because it gives too little or too much resolution to fit in the fixed length 4 bytes that are required. Vxxx battery volts in tenths 128 would mean 12.8 volts Zxx Device type These fields can either be added to a WX station report where the WX symbol would continue to be used, or the available weather data can be added to a Water Gage report using either of the two water symbols. The standard WX report allows for any field to be indicated as not available either by omission or by replacing the value with "...". SInce the wind direction and speed and temperature are required fields, this means the minimum weather report with flood info is WX symbol -plus- .../...t...VxxxFxxxx or the minimum water gauge report is Water symbol -plus- VxxxFxxxx/ZFA Notice that if water data is added to a WX report, then only Fxxxx and optional Vxxx are added to the WX report. But if WX data is added to a water gage report, then the minimum fields of wind direction and speed and temperature .../...t...Fxxxx are required. Examples are: Weather Station reports with flood gage readings: DDMM.hhN/DDDMM.hhW_ddd/sss/Gggg/Tttt/Fxxxx... DDMM.hhN/DDDMM.hhW_ddd/sss/Gggg/Tttt/Fxxxx/Vvvv... DDMM.hhN/DDDMM.hhW_ddd/sss/Gggg/Tttt/Rrrr/PppppFxxxx... Water Gage Object reports (w/o weather): ;09428508 *061713z3401.40N/11424.75Ww3.57gh/82cfs Water Gage Object reports with weather: DDMM.hhN/DDDMM.hhWwFxxxx/ZFA DDMM.hhN/DDDMM.hhWwFxxxxVvvv/ZFA DDMM.hhN\DDDMM.hhWwFxxxxVvvv/ZFA DDMM.hhN/DDDMM.hhWwddd/sss/Gggg/Tttt/Fxxxx/ZFA DDMM.hhN/DDDMM.hhWwddd/sss/Gggg/Tttt/FxxxxVvvv/ZFA DDMM.hhN\DDDMM.hhWwddd/sss/Gggg/Tttt/FxxxxVvvv/ZFA Water Gage reports (new): DDMM.hhNFDDDMM.hhW_Fxxxx/ZFA DDMM.hhNFDDDMM.hhW_FxxxxVvvv/ZFA DDMM.hhNFDDDMM.hhW_FxxxxVvvv/ZFA DDMM.hhNFDDDMM.hhW_ddd/sss/Gggg/Tttt/Fxxxx/ZFA DDMM.hhNFDDDMM.hhW_ddd/sss/Gggg/Tttt/FxxxxVvvv/ZFA DDMM.hhNFDDDMM.hhW_ddd/sss/Gggg/Tttt/FxxxxVvvv/ZFA Flood Hazards(new): DDMM.hhNFDDDMM.hhWHFxxxx/ZFA DDMM.hhNFDDDMM.hhWHFxxxxVvvv/ZFA DDMM.hhNFDDDMM.hhWHFxxxxVvvv/ZFA DDMM.hhNFDDDMM.hhWHddd/sss/Gggg/Tttt/Fxxxx/ZFA DDMM.hhNFDDDMM.hhWHddd/sss/Gggg/Tttt/FxxxxVvvv/ZFA DDMM.hhNFDDDMM.hhWHddd/sss/Gggg/Tttt/FxxxxVvvv/ZFA Notice that since 2006, existing software had to also consider parsing the appearance of any WATER or FLOOD symbols to see if they also include Weather. Also, everyone's weather parser needed to look at the WX fields for the optional additional Fxxxx or Vvvv fields. This has been simplilfied in addendum 1.2.1 so that only two APRS symbol groups need to be parsed for Weahter and other sensor data, that is the original *_ and *W for weather plus the new *H hazards. Parsing the old water gage data may be required until all legacy water gages are gone.? Comments? de WB4APR, Bob