The photo of a lifeless Syrian toddler who drowned as his family tried to cross the Mediterranean Sea last September shocked the world.The graphic image, shared widely by media outlets across the globe, sparked sharp calls for action to help refugee families.But nearly six months after young Aylan Kurdi's death , roughly two children a day are dying at sea, according to leading humanitarian aid officials — and the drownings are happening at an even higher rate than before.More than 340 children have died while crossing the eastern Mediterranean since September, the Office of the U.N. High Commissioner for Refugees, the U.N. Children's Fund, and the International Organization for Migration said in a joint statement Friday . That figure, which breaks down to an average of two drownings a day, includes many babies and toddlers.“These tragic deaths in the Mediterranean are unbearable and must stop,” U.N. High Commissioner for Refugees Filippo Grandi said in the statement.Subpar boats and life jackets, rough winter conditions, and continued demand for crossings — an estimated 80,000 refugees and migrants have attempted the journey since the start of 2016 —contribute to the high death roll. Officials estimate that more than a third of those making the journey are children.The three agency heads called for changes to make the process of seeking asylum in Europe less dangerous for families. High-level meetings on the topic are set to take place in Geneva in late March.“We cannot turn our faces away from the tragedy of so many innocent young lives and futures lost — or fail to address the dangers so many more children are facing,” UNICEF Executive Director Anthony Lake said in a statement. “We may not have the ability now to end the desperation that causes so many people to try to cross the sea, but countries can and must cooperate to make such dangerous journeys safer. No one puts a child in a boat if a safer option is available.”