A fleet of full­ scale paper boats is afloat on the Hudson River, charting a course from Troy to New York City in a convergence of art and activism to coincide with the meeting of world leaders at the United Nations Climate Summit. "SeaChange: We All Live Downstream" is a participatory voyage downstream intended to initiate a dialogue on climate change and engage communities in claiming the water as commons along the way. PLAY (2:29). Anyone with a boat or other sailing vessel is invited to join the fleet as it travels along a 160-mile path during the next two weeks. Events are planned at various locations, including a party tonight, Tues., Sept. 2, in Henry Hudson Riverfront Park. SeaChange is an initiative of the Brooklyn­-based boat-building collective Mare Liberum and 350 [dot] org.