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LOCATION MATTERS More about W3W, an algorithm designed for search and rescue on land and at sea
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how NSRI uses what3words LOCATION MATTERS:
NSRI Operations Manager Brett Ayres tells us more about W3W, an algorithm that divides the world into 3m x 3m squares that are each given a unique three-word ‘address’. The implications for search and rescue at sea and on land are incredible.
ONE OF THE CARDINAL considerations in performing a rescue, especially in the ocean, is location. Without location information and an effective means of communicating location, effective rescue cannot take place.
Traditionally the maritime language of location communication has been numeric, with a long string of coordinate numbers separated by various notations. To give a coordinate location with a resolution of about two metres entails the use of 23 characters: For example, the location of our rescue base at Wilderness is: 33° 55,735’ S 022° 34,965’ E.
Trying to communicate the above coordinate over a crackly radio or with a broken cellphone signal obviously takes time at best and at worst could lead to the wrong location being received. Similarly, the process of inputting 23 characters into a GPS device or cellphone on a moving vessel or in a vehicle on a bumpy road can be fraught with error. Lastly, a major problem lies in the fact that the coordinate used above is only one of three very similar coordinate ‘notations’. The example is in the main notation that NSRI uses: ‘degree, decimal minute’. At school, we were all taught the ‘degrees, minutes, seconds’ notation, whereas on Google Maps and other digital devices, ‘decimal degrees’ is becoming a new, frequently used standard. As rescuers, we often first need to determine which notation is being used by the person giving their location, and then mathematically convert it to our standard before we can use it, which takes even more time and opens up more possibility of error.
Enter an organisation called what3words (W3W). Having recognised the above challenges, which are not unique to NSRI, W3W developed an algorithm that simply and effectively divides the entire world into 3m x 3m squares that are each given a unique three-word ‘address’. Using W3W, the location of the front door of Wilderness NSRI base – jesters. sidestep.stingray – is much simpler and far easier to communicate and to enter on a smartphone.
Without going into the full detail of the system, it is set up in such a way that words that are phonetically similar, or where there is a risk of the word order being swapped, are
assigned to places very far from each other. So potentially confused words would relate to locations in, say, South Africa, China and South America. It is generally easy to know roughly which part of the world a person is referring to, so that is not a major problem. Generally, words that are more complicated are used for remote parts of the world, while developed places such as cities, have words that are shorter and simpler. Lastly, W3W is multilingual and available to use in Afrikaans, isiZulu, isiXhosa and English (as well as more than 30 other well-known global languages).
The W3W website (what3words. com) is free to use, and the app, which is available at both the Apple and Google Play stores, can be downloaded and used free of charge. It functions seamlessly with other native applications on your device, such as Google Maps or Uber. This enables you to use your phone to navigate to a given W3W address and saves you the hassle and error margin of long number coordinate strings. Furthermore, W3W is voice enabled and designed for use with speech recognition devices, which is becoming more and more prevalent as technology progresses. NSRI uses W3W in many ways. Our Pink Rescue Buoy project makes use of W3W location information for its precise locating and administration. NSRI also makes use of the W3W website, so if any member of the public calls in and describes their location using W3W, we use the app to determine where it is and to communicate such to the NSRI rescue stations.
Some of the NSRI Coastwatchers also utilise W3W, using the app on their cellphones to communicate their precise location, which can be plotted on a programme or chart and from which the bearing of the target that they are observing can be drawn, enabling us to establish a fix on a target.
Lastly, the most exciting use for NSRI of W3W comes into play when a person in distress occasionally calls in an emergency via their phone, but is unable to determine their own position. Over the years, this has resulted in numerous situations where rescuers are simply unable to start an effective search, because the potential search area is either unknown or so large that the chances of finding that person are virtually impossible. This includes people lost in thick fog off the West Coast, people on vessels whose electronics are not functioning and tourists lost in coastal forests, for instance.
In these situations, the NSRI EOC (Emergency Operations Centre) can SMS a unique URL to a lost person in distress, with an instruction to click on that link so that they can find the casualty’s location. The casualty, provided they have GPS and internet connectivity on their phone, then does so, enabling the phone to display its current location as a three-word address (this works even without having the app). Now the casualty can relay those three words to the operator over the phone. The operator can then input those words in the system, which locates the person to a unique 3m x 3m square, precisely locating them even in the thickest of fog.
Even better: if a person already has the W3W app on their phone they won’t even need internet connectivity on their device to relay the threeword address.
The app works completely offline once downloaded, making it an excellent choice for a day out in the bush, at the beach or on the water with your loved ones.
