Today I heard a man speak to his estranged son for the first time in over a decade. His voice shook as he spoke through a volunteer who translated the father's Haitian Creole into the son's mother tongue, French.

The father and son had last seen each other when the son was a baby, emigrating from Haiti to France in his mother's arms. Now, here in this crowded, muddy town square in Gonaives - a city ravaged by the global food crisis and then severe tropical storms - the father has this first tearful exchange with his son via a free, three-minute phone call.

I am one of the two teams of Telecoms Sans Frontieres (TSF) emergency telecommunications specialists who deployed to Haiti as it was hit by four cyclones - Fay, Gustav, Hanna and Ike - in less than a month.

TSF's teams deployed from bases in Nicaragua and in France to support communications both among humanitarian relief workers and for Haitians who had been driven from their homes by flood waters. The hub of emergency response efforts in Haiti is in Gonaives, a northern city that has been largely destroyed by the hurricanes.

Around 77,000 of Gonaives' residents have moved to temporary housing — crowded schools, churches or hospitals which have also been damaged by the storms. Countless more are staying in informal shelters, with family or friends. Our driver, for example, has been sheltering 20 people in his house for more than two weeks.

Gonaives is surrounded by hills ravaged by deforestation, triggering mudslides that pour into the city. Continuing heavy showers are frustrating the relief effort.

Mud chokes roadways and clogs houses, and while the water level is down, heavy rains are still triggering overflow from toilets and drainage pipes. Aid agencies fear the stagnating water will spread disease if it is not pumped out quickly.

I am on the team running a "humanitarian calling operation", which provides affected populations with free short phone calls to reconnect them with loved ones.

Since we launched our operation two days ago, it has been a tremendous success. Already more than 1,300 families have been able to contact relatives to ask for money or simply give them news for the first time since the cyclones hit Haiti.

Our team travels from shelter to shelter, reaching around two per day. We use satellite phones for international calls and mobile phones for domestic ones.

Access to satellite phones is very important since 80 percent of the calls go abroad. Of those, 90 percent are to the United States, mainly to Florida, but also to New York, Boston, Washington or Kansas.

There are many compelling testimonies to the importance of communications after disasters.

A few days ago, a 53-year old woman was able to call her father in Miami for the first time since the disaster. She thanked us because, even if her father wasn't able to send money, they were both very happy to exchange news. "It was so good to hear his voice. You gave me three minutes of happiness," she said.

Later, a man cried after calling his wife in Boston.

The Western Union office here has reopened, making TSF's calls even more important as people can now arrange money transfers. The Haitian diaspora is a huge source of revenue for many families living in Gonaives.

Normally, a three-minute call from Haiti costs around 135 gourdes ($3.45). To put that in context, a cup of rice (people don't count in kilos or pounds but in "cups") costs 35 gourdes.

For a population battered by the food crisis and then these storms, access to TSF's phone lines can mean not only moments of comfort connecting with loved ones, but also a potential lifeline to those who might send money.

Our calling operations should last several more days.

Watch a video of TSF's work:

TSF's deployment to Haiti is also providing communications support for U.N. Disaster Assessment and Coordination (UNDAC) teams and relief workers with the U.N. Children's Fund and agencies such as Medecins Sans Frontieres and the Spanish Red Cross. It is backed by partners including the European Commission Humanitarian Office (ECHO) and the UN Foundation and Vodafone Foundation Technology Partnership, which supports the use of emergency communications for disaster relief.

For more information about TSF, visit www.tsfi.org. For more information about the UN Foundation-Vodafone Foundation Technology Partnership's Emergency Communications for Disaster Relief program, visit www.unfoundation.org/vodafone.

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