Cop

The Conference of the Parties (COP) is the supreme decision-making body of the United Nations Framework Convention on Climate Change (UNFCCC). It brings together representatives from the treaty’s member states to negotiate and adopt decisions on climate policy, finance, technology transfer, and measurement, reporting, and verification guidelines. COP meetings are held annually in different locations and aim to advance the implementation of the Paris Agreement, including rules for national emissions targets and climate finance. Notable sessions include COP21 in Paris (adoption of the Paris Agreement) and COP26 in Glasgow.

Coefficient of Performance (COP) is a dimensionless metric of efficiency for heating and cooling devices. For a heat pump, COP = Qh / W, where Qh is heat delivered and W is work input. For refrigerators and air conditioners, COP = Qc / W, with Qc the heat removed. Higher COP values indicate greater efficiency, though COP depends on operating conditions such as temperature and load.

Chief of Police (COP) is a formal title for the head of a police department in many jurisdictions. The COP sets policy, oversees operations, and represents the agency in public and interagency matters. The role may be supported by deputies or assistants and is defined by local or national law and organizational rules.

Other uses of COP exist in various fields, reflecting the acronym's multiple meanings. The intended meaning is determined by context, geography, and the subject area.