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O

Ocean acidification

Ocean acidification refers to a reduction in the pH of the ocean over an extended period of time, caused primarily by uptake of carbon dioxide (CO2) from the atmosphere.

Ocean and islands

Ocean: The mass of water occupying all of the Earth's surface not occupied by land, but excluding all lakes and inland seas. Island: A land mass, especially one smaller than a continent, entirely surrounded by water.

Office of Foreign Disaster Assistance

An organisational unit within the United States Agency for International Development (USAID) responsible for leading and coordinating the U.S. Government's response to disasters overseas.

Office of the United Nations Disaster Relief Coordinator (see also OCHA)

UNDRO was previously a standalone organisation of the United Nations that assisted in the UN deliverance of disaster and emergency relief. In 1992 it was incorporated in the Department of Humanitarian Affairs of the UN Secretariat by the Secretary General.

Officials Domestic and External Security Committee (NZ)

A New Zealand government committee responsible for providing the Prime Minister with strategic policy advice and oversight on security and intelligence matters.

Opportunity Cost

The cost of an economic activity foregone by the choice of another activity.

Organisation internationale de la Francophonie

An international community, created in 1970, representing 80 member states and governments (57 members and 23 observers) where French is the customary language and where there is a notable affiliation with French culture. The IOF's mission is to embody the active solidarity between its member's states. IOF organises political activities and actions of multilateral cooperation that benefit French-speaking populations.

Organization for the Prohibition of Chemical Weapons

The implementing body of the Chemical Weapons Convention which prohibits the use of chemical weapons and requires their destruction. OPCW is comprised of 190 member states, working together to achieve a world free of chemical weapons.

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