The migrant crisis in Europe has reached a dire new milestone: in the first six months of 2015, 137,000 people crossed the Mediterranean searching for refuge from war, persecution and poverty, according to a new United Nations report—that’s an astounding 83% increase from the same period last year.

One in three of those arriving on European soil were from the war-torn Syria, followed by migrants from Afghanistan and Eritrea. Many of them come from refugee-hosting countries such as Lebanon that are struggling with maintaining camps and supplying aid. Most of the migrants should qualify for refugee status in Europe, according to the UN High Commission for Refugees (UNHCR).

“Europe has a clear responsibility to help those seeking protection from war and persecution,” said UNHCR chief António Guterres. “To deny that responsibility is to threaten the very building blocks of the humanitarian system Europe worked so hard to build. European countries must shoulder their fair share in responding to the refugee crisis, at home and abroad.”

An increasing number of migrants take the eastern Mediterranean route, from Turkey to Greece and then through the Balkan countries, which are ill-prepared for the influx.

This year’s situation was most dire in April, when 1,308 migrants perished during their journey, including 800 who drowned in one tragic accident off the coast of Libya. And even though May and June saw a decrease in deaths due to more effective EU search-and-rescue missions, historically most crossings occur in the second half of the year.

The report emphasizes another unfortunate reality: The migrant crisis in Europe is merely a small part of the global problem—86% of the world’s refugees remain in developing countries.