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wave height and wave frequency. The information is traditionally provided by the Harbormas- ter?s staff at a port, normally as a voice message using marine VHF radios in reply to a request. At some ports the live data is publically available through the authority?s web site or in some rare cases the data is provided electronically over AIS. Why Twitter? Twitter is a real-time information network service that con- nects to the latest information on a speci c topic the user  nds interesting. At the heart of Twitter are small bursts of informa- tion called Tweets. Each Tweet is up to 140 characters long, brief but concise information packets. Every day, millions of people use Twitter to connect to information about their in- terests and  nd out what?s happening in the world right now. Anyone can read, write and share messages of up to 140 char- acters on Twitter. These messages, or Tweets, are available to anyone (deemed as ?followers?) interested in reading them, whether logged in or not.In addition, there are some signi cant advantages to the me- dium, including:- Gauge location information embedded in tweets - UTC timestamp embedded in data tweets - Last two days tweets available directly on-line - User controlled tweet following and distribution - Data Tweets available as direct SMS message. - Data available by mobile web applications and clients. The TweetM8 gauge is PortM8 instrument programmed to send an SMS text message over a simple GSM modem ev- ery 10 minutes. The PortM8 equipment is an autonomous low power integrated tide gauge and weather station that can be powered by a small low voltage power adaptor or by a solar panel and rechargeable battery arrangement. The Tide Gauge element can be either a pressure transducer or a non-contact Radar sensor, the pressure transducer version has the bene t of also measuring water temperature while the radar senor has the bene t of non contact with the water level being measured The GSM modem is the preferred medium for communicating with the Twitter server, the modem?s tele- phone number identi es it when connecting to Twitter without any further security checks. Depending on the carrier service there is normally a short number which quickly connects the modem direct to Twitter without the need for area codes. The PortM8 only requires a minimum (12vdc 100ma) power sup- ply which is easily achieved with rechargeable batteries and a solar panel charging system. www.ohmex.net People, Company & Product News from Ocean Business Credit: Ohmex Instruments Twitter page showing PortM8 data. May 201344 MTRMTR #4 (34-48).indd 44MTR #4 (34-48).indd 445/6/2013 10:24:37 AM5/6/2013 10:24:37 AM