UNFCCC
The United Nations Framework Convention on Climate Change (UNFCCC) is an international environmental treaty whose objective is to “stabilize greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system”.
UNFCCC is also the name of the United Nations Secretariat charged with supporting the operation of the Convention, with offices in Bonn, Germany.
Their website is at https://unfccc.int/