The US president, who has repeatedly expressed doubt about the overwhelming scientific consensus on manmade causes of global warming, was due to attend a separate conference on religious freedom.
However, he first dropped in on the climate summit, where he spent just a few minutes.
Dozens of world leaders were discussing measures to try and slow down ever-more dangerous trends in climate change. Trump, who withdrew the United States from a major international pact on reducing greenhouse gas outputs, did not speak.