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Posts tagged San Francisco Bay

Bridges Spanning Bays by San Francisco, USA

37.7N 122.4W

November 10th, 2009 Category: Snapshots

California, USA - October 22nd, 2009

California, USA - October 22nd, 2009

The city of San Francisco, California, can be seen along the shores of the San Francisco Bay in this orthorectified image. A series of bodies of water are visible, as the San Francisco Bay (bottom right quadrant) is connected to the San Pablo Bay to the northwest, which in turn is joined with the Suisun Bay, above the image center.

The bridges spanning these bays appear as thin white or light grey lines in this ASAR image. These are, moving from the center to the lower right corner, the Richmond-San Rafael Bridge, the San Francisco-Oakland Bay Bridge, the San Mateo-Hayward Bridge, and the Dumbarton Bridge.

Sediments in Interconnected San Francisco Bays, California, USA – October 26th, 2009

37.7N 122.4W

October 26th, 2009 Category: Image of the day, Rivers

California, USA - August 25th, 2009

California, USA - August 25th, 2009

Sediments from the Sacramento and San Joaquin Rivers flow through a group of interconnected bays in California often collectively referred to as the San Francisco Bay, before spilling out into the Pacific Ocean.

Along this path, the sediments actually flow first into Suisun Bay, which then flows through the Carquinez Strait to meet with the Napa River at the entrance to San Pablo Bay, which in turn connects at its south end to the true San Francisco Bay.

The cities of this region, including San Francisco, Oakland and San Jose, can be seen as grey areas near and along the shores of the bays.

Point Reyes, the Marin Hills and San Francisco, California

38.0N 122.8W

August 7th, 2009 Category: Snapshots

California, USA - July 3rd, 2009

California, USA - July 3rd, 2009

Water currents in the Pacific Ocean off the west coast of California make interesting patterns as they swirl around Point Reyes (top) and out of the San Francisco Bay (right).

Point Reyes is a prominent cape in Marin County approximately 30 mi (48 km) west-northwest of San Francisco. The term is often applied to the Point Reyes Peninsula, the region bounded by Tomales Bay on the northeast and Bolinas Lagoon on the southeast. The headland is protected as part of Point Reyes National Seashore. In this orthorectified image, Inverness Ridge can be seen running along the peninsula’s northwest-southeast spine.

To the southeast, the city of San Francisco glows at the northern end of the San Francisco Peninsula, with the Pacific Ocean to the west and San Francisco Bay to the east. The Golden Gate Bridge can be seen connecting the peninsula to the Marin Hills in southern Marin County.

Part of the San Francisco-Oakland Bay Bridge (to the right of the Golden Gate) and the Richmond-San Rafael Bridge (above the Bay Bridge) can also be seen.

Bridges of the San Francisco Bay Area – July 24th, 2009

37.7N 122.4W

July 24th, 2009 Category: Image of the day

USA - July 9th, 2009

USA - July 9th, 2009

This orthorectified image offers a sharp view of San Francisco and the Bay Area in California, USA. The large bay in the bottom right quadrant is the San Francisco Bay, which connects to the San Pablo Bay to the northwest, which in turn connects to the Suisun Bay, upper right quadrant.

Several bridges can be seen crossing these bays, including the famous Golden Gate Bridge, close to the center, the San Mateo-Hayward Bridge, spanning the lower part of the San Francisco Bay, the San Francisco-Oakland Bay Bridge, east of the Golden Gate, and the Richmond-San Rafael Bridge, below San Pablo Bay.

Also of note is the San Francisco International Airport, whose main runways appears as a black cross on the western shores of the San Francisco Bay.

Clouds and Fog Along the California Coast – June 1st, 2009

37.7N 122.4W

June 1st, 2009 Category: Clouds

West Coast, USA - May 25th, 2009

West Coast, USA - May 25th, 2009

San Francisco Bay

San Francisco Bay

Here, the coast of California is framed by a blanket of clouds and sea fog. Fog begins to form when water vapor (a colorless gas) condenses into tiny liquid water droplets in the air. Fog normally occurs at a relative humidity near 100%.

Another common type of formation is associated with sea fog (also known as haar or fret), due to the peculiar effect of salt. Clouds of all types require minute hygroscopic particles upon which water vapor can condense. Over the ocean surface, the most common particles are salt from salt spray produced by breaking waves.

Except in areas of storminess, the most common areas of breaking waves are located near coastlines, hence the greatest densities of airborne salt particles are there.

Condensation on salt particles has been observed to occur at humidities as low as 70%, thus fog can occur even in relatively dry air in suitable locations such as the California coast, as shown here. Typically, such lower humidity fog is preceded by a transparent mistiness along the coastline as condensation competes with evaporation, a phenomenon that is typically noticeable by beachgoers in the afternoon.

The close-up focuses on San Francisco, where the combination of cold ocean water and the high heat of the California mainland create the city’s characteristic fog that can cover its western half all day during the spring and early summer. The fog is less pronounced in eastern neighborhoods, in the late summer, and during the fall, which are the warmest months of the year.

The high hills in the geographic center of the city protect neighborhoods directly to their east from the foggy and cool conditions experienced in the Sunset District; for those who live on the eastern side of the city, San Francisco is sunnier, with an average of 260 clear days, and only 105 cloudy days per year.