|Gulf of Alaska|
|Location||South shore of Alaska|
|Part of||North Pacific Ocean|
|River sources||Susitna River|
|Basin countries||Canada and United States|
|Surface area||1,533,000 km2 (592,000 sq mi)|
|Islands||Kodiak Archipelago, Montague Island, Middleton Island, Alexander Archipelago|
The Gulf of Alaska (Tlingit: Yéil T'ooch’) is an arm of the Pacific Ocean defined by the curve of the southern coast of Alaska, stretching from the Alaska Peninsula and Kodiak Island in the west to the Alexander Archipelago in the east, where Glacier Bay and the Inside Passage are found.
The Gulf shoreline is a combination of forest, mountain and a number of tidewater glaciers. Alaska's largest glaciers, the Malaspina Glacier and Bering Glacier, spill out onto the coastal line along the Gulf of Alaska. The coast is heavily indented with Cook Inlet and Prince William Sound, the two largest connected bodies of water. It includes Yakutat Bay and Cross Sound. Lituya Bay (a fjord north of Cross Sound, and south of Mount Fairweather) is the site of the largest recorded tsunami in history. It serves as a sheltered anchorage for fishing boats.
The Gulf of Alaska is considered a Class I, productive ecosystem with more than 300 grams of carbon per square meter per year based on SeaWiFS data.
Deep water corals can be found in the Gulf of Alaska. Primnoa pacifica has contributed to the location being labeled as Habitat Areas of Particular Concern. P. pacifica is a deep water coral typically found between 150 metres (490 ft) and 900 metres (3,000 ft) here.
Thanks to Gulf Stream, while the Okhotsk Sea was "closed by ice in winter", just 10° further north, the "Gulf of Alaska was ice-free throughout the year". In 1977, the Gulf of Alaska started to manifest an unexpected and at that time inexplicable shift on its normal climate regime, resulting in a growth of the mean temperature of the sea surface and in an increased availability and variety of commercial fish species. A similar volatile climate change was observed during the 1970s in the North Pacific seas.
The Gulf is a great generator of storms. In addition to dumping vast quantities of snow and ice on southern Alaska, resulting in some of the largest concentrations south of the Arctic Circle, many of the storms move south along the coasts of British Columbia, Washington, Oregon, and as far south as Southern California (primarily during El Niño events). Much of the seasonal rainfall and snowfall in the Pacific Northwest and Southwestern United States comes from the Gulf of Alaska.
The International Hydrographic Organization defines the limits of the Gulf of Alaska as follows:
On the north. The coast of Alaska.
On the south. A line drawn from Cape Spencer, the northern limit of the Coastal Waters of Southeast Alaska and British Columbia to Kabuch Point, the southeast limit of the Bering Sea, in such a way that all the adjacent islands are included in the Gulf of Alaska.
The US Geological Survey's Geographic Names Information System database defines the Gulf of Alaska as bounded on the north by the coast of Alaska and on the south by a line running from the south end of Kodiak Island on the west to Dixon Entrance on the east.