Migrant women from Nigeria are rescued from a small boat bound for Italy, about 17 miles north of Sabratha, Libya, on Aug. 28. (Emilio Morenatti/AP)

Toward the end of summer, warmer weather and calmer seas have brought a spike in attempted migrant passages across the Mediterranean, many of them life-threatening.

This past week, the Italian coast guard reported rescuing approximately 6,500 migrants off the Libyan coast as part of the summer spike along the central Mediterranean route, from North Africa to the Italian peninsula and its outer islands.

The incident was the latest in a long summer of similar occurrences in which makeshift and ill-equipped boats have frequently capsized in dangerous waters. Drownings have been reported for months off the coasts of Cyprus, Sicily and Libya.

The summer of 2016 has marked a dark new chapter in Europe’s migrant crisis, the largest in European history since the upheavals of 1945, with more than a million people having arrived on the continent in the past year alone.

The numbers of migrants from the Middle East and Africa who have made these sea crossings to European ports — mostly in Greece and Italy — have gradually declined this year. Despite the lower numbers, fatalities have actually risen.

According to the International Organization for Migration, nearly 280,000 migrants and refugees entered Europe by sea in the first eight months of 2016, compared with nearly 355,000 in the same period last year.

But through the end of August, more than 3,000 migrants and refugees have drowned in the Mediterranean, at least 500 more than at this point last year, the IOM reports.

In a year that has seen the European Union confronted with some of its greatest challenges since its establishment, many have begun to consider these fatalities as inevitable collateral damage in a continent preoccupied with processing migrants when they arrive and the aftermath of Britain’s vote to leave the E.U. altogether.

The composition of the ­Brussels-based bloc often has impeded any comprehensive, unified plan for processing migrants who come by sea. And Frontex, the E.U.’s border-control agency, relies on particular member states to provide the equipment and vessels the agency needs in the Mediterranean. As a result, migrant rescues in the Mediterranean have been conducted largely through a combination of governmental and nongovernmental initiatives, with the coast guards of Libya and Italy and organizations such as Doctors Without Borders and Greenpeace carrying out search operations.

According to Marc Pierini, a former E.U. ambassador to Libya and Syria, in theory the E.U. has sought cooperation from African states in curbing the flow of migrants, but certain governments are reluctant to take any actions that curb an emerging people-smuggling trade that has proved lucrative.

“A lot of people are making money along the way,” he said. “Not only in terms of repression costs, but on top of that, the flow of illegal money is huge compared to the national wealth.”

“You have to compare this phenomenon to growing cocaine in cocaine-producing countries,” he said. “There’s nothing legal that matches the money that people can make growing illegal stuff. That is the hard reality.”

Meanwhile, along the other major migrant sea route into Europe — from the Middle East through the eastern Mediterranean and into the Greek islands — this past week saw more than 460 migrants and refugees arrive on the islands of Lesbos and Kos.

In a landmark deal that the E.U. signed with Turkey in March, this route was supposed to be closed in exchange for the E.U. considering visa liberalization for Turks seeking to live and work in Europe, as well as the prospect of Turkey’s admission to the 28-member bloc.

After the attempted coup against the Turkish government in July, the deal may no longer stand. European officials have objected to alleged human rights abuses by the Turkish government, and Turkey is frustrated that visa liberalization, five months after the agreement, has not been granted.

Under the terms of the deal, migrants who crossed from Turkey to Greece without proper documentation are supposed to be returned to Turkey, unless they have successfully applied for asylum in Europe.

An E.U. official involved in migration and counterterrorism talks said that this past week’s spike in migrant arrivals in Greece did not necessarily suggest a Turkish abandonment of the March agreement.

“I don’t think it’s an effect of the coup,” said the official, who spoke on the condition of anonymity because he was not authorized to speak publicly. “I know they’re putting the visa liberalization on the table at the moment, but I haven’t seen any effect in numbers.”

On Friday, E.U. ministers arrived in Bratislava, Slovakia, for informal talks with Turkish officials to discuss the political developments in Turkey as well as the future of the country’s relations with the E.U.

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