There are a number of excellent maps being generated using the Google Maps API. But one that caught my attention was the map of piracy incidents plotted using data from the IMB Piracy Reporting Centre of the ICC International Maritime Bureau .
The ICC International Maritime Bureau (IMB) is a specialised division of the International Chamber Of Commerce (ICC). The IMB is a non-profit making organisation, established in 1981 to act as a focal point in the fight against all types of maritime crime and malpractice.
IMB’s main task is to protect the integrity of international trade by seeking out fraud and malpractice. For over 20 years, it has used industry knowledge, experience and access to a large number of well-placed contacts around the world to do this: identifying and investigating frauds, spotting new criminal methods and trends, and highlighting other threats to trade.
They also issue a weekly piracy report which is a summary of the daily reports broadcast by the IMB’s Piracy Reporting Centre to ships in Atlantic, Indian and Pacific Ocean Regions on the SafetyNET service of Inmarsat-C.
In my section on using mobile phones on board I keep referring obliquely to “modern phones”. One reader picked me up on this and asked me all sorts of questions about their phone. Unfortunately the reader was in the States so I did little bit of research on what is going on in the US with the mobile phones network. This is one technology where we in Europe can justly feel proud of the advanced technology that we get to use compared with our poor cousins in the USA,…sorry
Firstly – since many readers of this blog are all over the world you may have all sorts of technology being deployed at the same time even some quite old ones so watch out – even your laptop mobile broadband dongle that you just bought may still be out of date technology.
Originally data transmissions – which is what we are interested in on our boat – was sent over the analogue mobile phone network in much the same way as modems used to send data over computer dial up networks – i.e. as sounds -this practice even continued when the first GSM mobile network was deployed.
Stage 1 – CSD
The first digital systems for data was Circuit Switched Data (CSD). This is a real digital transmission of data using the GSM network. Unfortunately when the transmission left the GSM network to go to the internet for example – the transmission was converted back to analogue – and was not IP based – which is how the internet transmits data around the world. Data transfer was relatively slow: 14.4 kbps (kilobits per second) for GSM 1800 networks (Orange and T-Mobile) and 9.6 kbps for GSM 900 networks (Vodafone and O2).
Stage 1a – HSCD
HSCSD (High Speed Circuit Switched Data) enables data to be transferred more rapidly than the standard GSM (Circuit Switched Data) system by using multiple channels. The maximum number of timeslots that can be used is four, giving a maximum data transfer rate of 57.6 kbps (or 38.4 kbps on a GSM 900 network). HSCSD is more expensive to use than GPRS, because all four slots are used simultaneously – it does not transmit data in packets. Because of this, HSCSD is not as popular as GPRS and is being replaced by GPRS/EDGE.
Stage 2 – GPRS (or 2.5G)
Following this came GPRS – General Packet Radio Service. This is sometimes called 2.5G. This brought a full data channel of about 32/48kb/sec via the GPRS service to/from the internet. Most Blackberries use GPRS it is perfectly ok for email and light internet access. The class of a GPRS phone determines the speed at which data can be transferred. Technically the class refers to the number of timeslots available for upload (sending data from the phone) or download (receiving data from the network). The timeslots used for data are in addition to the slot that is reserved for voice calls. These timeslots are available simultaneously, so the greater the number of slots, the faster the data transfer speed. Because GPRS transmits data in packets, the timeslots are not in use all the time, but are shared amongst all users of the network. That increases the overall data capacity of the network, and it also means that you are billed for the quantity of data transmitted, not the time that you are online. It may mean that during busy times, data transfer rates slow down, because the network will give priority to voice calls.
GPRS Class
Time slot
Max Data Transfer Speed
Class 2
3
8 – 12 kbps upload / 16 – 24 kbps download
Class 4
4
8 – 12 kbps upload / 24 – 36 kbps download
Class 6
4
24 – 36 kbps upload / 24 – 36 kbps download
Class 8
5
8 – 12 kbps upload / 32 – 40 kbps download
Class 10
5
16 – 24 kbps upload / 32 – 48 kbps download
Class 12
5
32 – 48 kbps upload / 32 – 48 kbps download
Stage 2a – EDGE
An enhancement of GPRS is called EDGE or “Enhanced Data rates for GSM Evolution” – aren’t acronyms great EDGE increases the speed of each timeslot to 48 kbps and allows the use of up to 8 timeslots, giving a maximum data transfer rate of 384 kbps.
Stage 3 – UMTS (or 3G)
This is the minimum standard for what I am calling a “modern phone”. Throughput should be up to 384kb/sec but because UMTS uses a different radio frequency to GPRS/GSM you should see a separate icon on your phone display indicating whether you have a “3G” signal or not. You can have one and not the other.
Stage 4 – HSDPA (or 3.5G)
An enhancement to UMTS/3G is High Speed Download Packet Access (HSDPA). This can give throughput from 14Mb/sec (downlink) and 6Mb/sec (uplink) – depending on your phone provider and proximity to a 3G aerial. This is sometime called 3.5G…
In the States they dont follow these standards of course ! They use CDMA (Code division multiple access)..
The bottom line is that your “modern phone” in Europe at least..should have options to access data and the internet using all the standards from 2G upwards. These should be selectable in the configurations so that you can choose to not use HSDPA fro example if you suspect that you happen to be somewhere where there is a lot of competition for that signal e.g St Katherines Dock in the City of London, or Gosport Marina in Portsmouth perhaps – then setting your phone “down” to 2G or 2.5G may in fact get a better uncontended link to the local aerial and therefore better internet access on the phone, laptop dongle or laptop connected by phone to the internet.
There are a number of subscription services for weather data, but I really think that whether you are experienced or a novice sailor it is a good idea to practice reading barometric and other weather data for yourself to get accustomed to the connection between the data and the summary weather forecasts that are available from the US and UK Met Office. Please note I am not saying that you can substitute for listening to and heeding the Inshore and Shipping forecasts – but these resources and sofware can help your own decision making in terms of passage planning.
Of course what the paid for services add is “interpretation” and “prediction”…and we all know how accurate the weather forecast is on the TV…well in England that would be funny – perhaps the weather is forecast accurately in your part of the World? There are many models for forecasting but the most prevalent is the US National Center for Environmental Prediction (NCEP) – GFS Model.
Below are a large number of free resources and software that would make you fully capable of seeing all sorts of up to date weather data for FREE.
Links: NOAA Marine Weather Service
This fantastic site gives free TIFF and GIF images for:
- WIND/WAVE CHARTS
- SURFACE CHARTS
- UPPER AIR CHARTS
- TROPICAL CYCLONE/HIGH WIND WAVE CHARTS
- ICE CHART
- SATELLITE IMAGERY
You don’t even need fancy software to see these pictures – just double click and the browser (IE or Firefox) will just display the picture for you – and you can save them to your laptop/PC for viewing later when you may not be able to get an internet connection. NOAA Radiofax Schedule (for any fax viewing software – see below)
GRIB file data goes a step further by giving wind direction and speed using an easy to understand “barbed feather”. This saves you having to measure the distance between isobars to calculate wind strength. Some software even draws isotechs which are lines of constant wind speed. and some software draws arrows of different dimension and colours to represent speed and direction.
But, I use the simple free service from UGRIB. This service gives you a free worldwide viewer and free GRIB files for any area that you care to select. You can select GRIB file area by just drawing an area on the map of the world and then the software downloads that area’s data alone – thereby saving on bandwidth for the download, which si a real boon if you are connected to the internet using your GPRS enabled phone! – click on the image for a larger screen shot.
Links:
Free GRIB viewer and GRIB data file – UGRIB
Free GRIB data – SAILDOCS
Free GRIB data viewer from AIRMAIL
If you have an SSB receiver on board such as the NASA SSB, then you can even get all sorts of free data while on the high seas and no where in sight of an internet connection…yes there are places such as these!
WEFAX is a method to transmit weather facsimile images over radio. Most images are transmitted in black and white, although some are grey scale. To receive wefax images, you need a shortwave receiver and a software decoder to convert audio tones into black and white. Tuning the receiver accurately is a tricky and time consuming process, but essential to receive acceptable pictures. You then have to clean up the audio signal by appropriate filtering to isolate the black and white “tones”.
The connection from the NASA SSB is a cable that plugs into the microphone input on my laptop, and when in operation sounds just like a fax machine or old analogue modem.
The program I use is SeaTTY. This can receive weather reports, navigational warnings and weather charts transmitted in RTTY, NAVTEX and HF-FAX (WEFAX) modes on longwave and shortwave bands. It can decode GMDSS DSC (HF and VHF) messages. The software can also automatically save NOAA Weather Radio SAME voice messages (NWR SAME) and the digital headers. No additional hardware is required — you need only a receiver and computer with a sound card.
The Memory Map application for mobile phones and PDA’s is fantastic example of software development for mobile devices. This application has been around for some time, and is the work of US based developer Richard Stevens and his team. Richard is a software developer with 15 year’s experience in scientific super-computing and high-performance real-time systems such as medical imaging machines and high-end radar systems.
From the MemoryMap web site …
“Memory-Map Weather Radar is an application to display live National Weather Service doppler radar images and animated loops from radars located throughout the United States. Radar is the most effective tool to detect precipitation, especially thunderstorms, and has been used by NWS forecasters since the 1940′s. Memory-Map now brings this information, conveniently and efficiently, right to your phone or PDA.
With Memory-Map Weather Radar, when you update the image, the radar data is downloaded as a compressed overlay, without having to download the whole base image each time. There are no usage fees or subscriptions for using the service, except your mobile carrier’s normal data access fees. If the sky is clear, the download is only 1 or 2 kbytes; if there is widespread rain, it might be 10 kbytes. The first time you view each radar station, the base map image is downloaded, which is 50 to 100kbytes….”
Although the radar product is limited to the USA, what I didn’t realise is that his company has produced a full navigation product Memory-Map Navigator – for hiking and sailing that covers the UK!. Take look at the excellent video here.
This takes the use of the built in GPS on a smartphone into a whole different realm….
I use a Raymarine C120, it can display tidal flow and even “animate” the flow over time, it is fully interfaced to my instruments for wind, and speed – but alas what it doesn’t do is:
a. Tell me precisely what time it is using – yes I know I should know – but why can’t it tell me it is set to UTC or GMT or BST or whatever at the point when I need it i.e. when I am calculating a route! This is critical to working out the time of HW at your reference port of departure, and then the tidal flow for each hour of the passage.
b. The tidal flow is not connected to any sort of calculation of course to steer – so you have to leave your 3,000 dollar technology and get your pencil and notepad out to calculate CTS.
On a recent trip from Dieppe to Brighton, this is a representation of the scribble I had to do to calculate CTS. This is after adding all the tides West and then East along the English Channel for the exact time of day and the duration in hours of the planned passage. Since the passage is at least 12 hours for a normal yacht averaging 5/6kts there will be two tides almost cancelling each other out at this part of the Channel. According to my calculations the net effect was in fact an easterly tide of about 1.5Kts.
There was – luckily – a steady W wind leaving me to hold a close reach all the way (except when avoiding cargo vessel in the Traffic Separation Zone!). But this increased leeway on my rather heavily built 32ft sloop so I used 7 degrees leeway in my calculations.
Giving a final Course to Steer of 310 degrees M.
The other issues is that since the predicted track is not displayed on the C120 screen, you don’t get an easy time estimating whether there are any dangers to avoid if you stick with your course to steer. Crossing the English Channel that is not normally such a problem – but there could easily be an island, a rock, an oil rig or even a wind farm in the way…
Naturally the CTS of 310 degrees M that I steered gave me the banana shape course over the ground rather than the red line that the C120 shows as the course between the beginning and end of this journey. (Click on the adjoining screen shot for a larger image.)
So, a plea to Raymarine – please update the C and E series software to do what programs such as Neptune and SeaPro can do !
That would be far more useful than an aerial photo of Dieppe!
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There are a number of excellent maps being generated using the Google Maps API. But one that caught my attention was the map of piracy incidents plotted using data from the IMB Piracy Reporting Centre of the ICC International Maritime Bureau .
August 27th, 2008|
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The Memory Map application for mobile phones and PDA’s is fantastic example of software development for mobile devices. This application has been around for some time, and is the work of US based developer Richard Stevens and his team. Richard is a software developer with 15 year’s experience in scientific super-computing and high-performance real-time systems such as medical imaging machines and high-end radar systems.
Weather Service doppler radar images and animated loops from radars located throughout the United States. Radar is the most effective tool to detect precipitation, especially thunderstorms, and has been used by NWS forecasters since the 1940′s. Memory-Map now brings this information, conveniently and efficiently, right to your phone or PDA.
On a recent trip from Dieppe to Brighton, this is a representation of the scribble I had to do to calculate CTS. This is after adding all the tides West and then East along the English Channel for the exact time of day and the duration in hours of the planned passage. Since the passage is at least 12 hours for a normal yacht averaging 5/6kts there will be two tides almost cancelling each other out at this part of the Channel. According to my calculations the net effect was in fact an easterly tide of about 1.5Kts.
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