As part of a national ecosystem review of large ocean management areas, this report examines the marine ecosystem of the Pacific North Coast Integrated Management Area (PNCIMA). PNCIMA encompasses approximately 102,000 km2 from the edge of the continental shelf east to the British Columbia mainland. The region extends from the British Columbia-Alaska border south to Bute Inlet on the mainland, across to Campbell River on the east side of Vancouver Island and the Brooks Peninsula on the west side of Vancouver Island. This report updates information from a major 2007 review. Wet windy winters and drier, relatively calmer summers dominate the seasonal weather, resulting from very different air pressure patterns In the Gulf of Alaska in summer and winter. Frequent winter storms with strong southerly winds (blowing from the south) bring not only high waves, but also warmer waters from the south and deep downwelling and mixing of surface waters. Relatively calmer weather in summer with periods of northerly winds brings calmer seas and allows nutrients from deep waters to reach the surface. Intense rainfall in late autumn and winter along the Coast Mountains provides massive input of fresh water along the eastern side of PNCIMA. Large rivers from the BC interior snowfields and glaciers dominate the fresh water runoff in other seasons, especially in late spring. Although this summer-winter change in weather dominates PNCIMA, there have been variations in the weather over past decades that have impacted PNCIMA. Some of these variations in the weather and their impacts are listed below. In addition, we summarise recent ecosystem research not necessarily related to changes in weather and climate.