When African leaders gathered in the Dutch city of Rotterdam this week to find solutions and money for climate change adaptation, only one European head of state joined them in person.

Senegalese President Macky Sall said richer nations' failure to come to the table and discuss how to pay for climate damage they have caused was disappointing — an issue set to be high on the agenda in upcoming U.N. climate talks in November in Egypt.

"I cannot help but note with some bitterness the absence of leaders from the industrial world," he said at the Africa Adaptation Summit, adding he had thought the meeting being held in Europe would make it "easier" for them to attend.