Overview
The Golden Gate is a strait on the west coast of North America that connects San Francisco Bay to the Pacific Ocean. It is defined by the headlands of the San Francisco Peninsula and the Marin Peninsula, and, since 1937, has been spanned by the Golden Gate Bridge. The entire shoreline and adjacent waters throughout the strait are managed by the Golden Gate National Recreation Area.
Geology
During the last ice age, when sea level was several hundred feet lower, the waters of the glacier-fed Sacramento River and the San Joaquin River scoured a deep channel through the bedrock on their way to the ocean. (A similar process created the undersea Hudson Canyon off the coast of New York and New Jersey.) The strait is well known today for its depth and powerful tidal currents from the Pacific Ocean. Many small whirlpools and eddies can form in its waters. With its strong currents, rocky reefs and fog, the Golden Gate is the site of over 100 shipwrecks.
Climate
The Golden Gate is often shrouded in coastal fog, especially during the summer. Heat generated in the California Central Valley causes air there to rise, creating a low pressure area that pulls in cool, moist air from over the Pacific Ocean. The Golden Gate forms the largest break in the hills of the California Coast Range, allowing a persistent, dense stream of fog to enter the bay there. Although there is no weather station on Golden Gate proper, the area has a mediterranean climate (Köppen Csb) with very narrow temperature fluctuations, cool summers and mild winters. For the nearest weather station see the weatherbox of San Francisco. The Golden Gate Bridge being nearer the ocean and at elevation indicate it being cooler during summer days. Nearer the San Francisco urban core, the temperatures resemble the official NOAA weather station instead.
From Wikipedia (CC BY-SA 4.0).