Northern California is not a formal geographic designation. California's north-south midway division is around 37° latitude, near the level of San Francisco. Popularly, though, "Northern California" usually refers to the state's northernmost 48 counties. This definition coincides with the county lines at 35° 47′ 28″ north latitude, which form the southern borders of Monterey, Kings,Tulare and Inyo counties. The term is also applied to the area north of Point Conception and the Tehachapi Mountains.
Because of California's large size and diverse geography, the state can be subdivided in other ways as well. For example, the Central Valley is a distinct region in itself both culturally and topographically from coastal California, though in northern versus southern California divisions, the Sacramento Valley and most of the San Joaquin Valley are usually placed in northern California.
The state is often considered as having an additional division north of the urban areas of the San Francisco Bay Area andSacramento metropolitan areas. Extreme northern residents have felt under-represented in state government and in 1941 attempted to form a new state with southwestern Oregon to be called Jefferson, or more recently to introduce legislation to split California into two or three states. The coastal area north of the Bay Area is referred to as the North Coast while the interior region north of Sacramento is referred by locals as the Northstate.
Northern California's diverse geography ranges from the sandy beaches of the Pacific coast to the rugged, snow-capped Sierra Nevada mountains in the east. The central portion of the region is dominated by the Central Valley, one of the most vital agricultural areas in the country. The Sierra Nevada contains Yosemite Valley, famous for its glacially-carved domes, and Sequoia National Park, home to the largest trees on Earth, the giant sequoia trees, and the highest point in thecontiguous United States, Mount Whitney. The tallest living things on Earth, the ancient redwoodtrees, dot the coastline, mainly north of San Francisco, and in the Santa Cruz Mountains. It also includes one of the largest Brackish-Marsh's in Western United States, Suisun Marsh. The area is also known for its fertile farm and ranch lands, wine country, the high mountains of the southernCascade Range, the Trinity Alps, and the Klamath Mountains, lakes, and the windswept sagebrushsteppe, in the northeast portion of the region.
Lake Shasta, located between the north end of the Sacramento Valley and Mount Shasta, is the largest reservoir, and is the third largest body of water after Lake Tahoe and the Salton Sea, in California. It was created by the construction of Shasta Dam across the Sacramento River, which was completed in 1945.
The climate can be generally characterized by its marine to warm Mediterranean climates along the coast, to somewhat Continental Mediterranean Climate in the valley to alpine climate zones in the high mountains. Apart from the San Francisco Bay Area and Sacramento metropolitan areas (and some other cities in the Central Valley), it is a region of relatively low population density.
Northern California's economy is noted for being the de facto world leader in industries such as high technology (both software and semiconductor), as well as being known for clean power, biomedical, government, and finance. Other significant industries include tourism, shipping, manufacturing, and agriculture. Its economy is diverse, though more concentrated in high technology, and subject to the whims of venture capital than any other major regional economy in the nation especially within Silicon Valley, and less dependent on oil and residential housing than Southern California. It is home to the state capital, as well as several Western United States regional offices in San Francisco, such as the Federal Reserve and 9th Circuit Court.