Around 3,000 delegates gathered here for talking over further implementation of the Paris agreement on climate change, as well as for preparation for the next session of the Conference of the Parties (COP23) to the UN Convention on Climate Change (UNFCCC) which is to be held November in Bonn.
The ten-day conference consists of three main sessions, according to the schedule released by UN, namely the session of the Subsidiary Body for Implementation(SBI), the session of Subsidiary Body for scientific and Technological Advice(SBSTA), as well as the third part of the first session of the Ad Hoc Working Group on the Paris Agreement (APA).
Though it isn't an official topic, global concerns over the uncertainty that the new U.S. government would probably exit Paris Agreement are casting shadow over the conference.
U.S. president Donald Trump said last month on his 100th day in office that he would make a "big decision" on Paris within the next two weeks.
The Paris Agreement was agreed by the 195 member economies that attended the 21st session of the Conference of the Parties (COP21) to UNFCCC 2015 in Paris.
"That 195 countries have agreed on binding targets is huge achievement, which shall not be endangered," Jochen Flasbarth, state secretary of the German Environment Ministry, told the opening plenary.
