Thursday, January 30, 2014

DAY 665

False Color
© Kyle Yates Photography, 2014
ALL RIGHTS RESERVED
True Color
© Kyle Yates Photography, 2014
ALL RIGHTS RESERVED
The Roberto Clemente Bridge, also known as the Sixth Street Bridge, spans the Allegheny River in downtown Pittsburgh, Pennsylvania, United States.
The Sixth Street Bridge that we see today is not the original Sixth Street Bridge. In 1859, the first Sixth Street Bridge was built by John Roebling which built this bridge as his third and final bridge. The original bridge had two main spans of 344 feet (105 m) with shore spans of 177 and 171 feet (54 and 52 m). The floors were suspended from wire hangers that were then suspended from wire catenaries. Eventually, due to electric streetcars, heavy loads, and more traffic, the bridge demanded to be wider and much more rigid so it came down in 1892. Then in 1892, the second Sixth Street Bridge was built by an engineer named Theodore Cooper for the Union Bridge Company. The main spans were 440 feet (130 m) long, each having through trusses of the camel-back type with upward-angled upper chords, and were twice as wide as the previous bridge. In 1927 the bridge had to be taken apart because the steelwork was too brittle for safety. So in 1927, the main spans were somewhat trimmed down temporarily from their 80-foot (24 m) height which were then lowered onto barges and floated down the Ohio river to the back channel of Neville Island. Finally in 1994 the steel was scrapped.
Named for the Pittsburgh Pirates baseball player Roberto Clemente, it is one of three parallel bridges called The Three Sisters, the others being the Rachel Carson Bridge and the Andy Warhol Bridge. The Three Sisters are self-anchored suspension bridges and are significant because they are the only trio of nearly identical bridges—as well as the first self-anchored suspension spans—built in the United States. Over 720 bridges link the city districts.
The Sixth Street Bridge's piers were built with arched openings beneath the river bed in order to accommodate future subway tunnels, following the recommendation of transportation planner Bion J. Arnold. The North Shore Connector tunnels completed in 2012 did not make use of this provision, but were bored further west (downstream) and do not pass beneath the bridge.
The bridge was renamed on August 6, 1998, as part of a compromise after the Pirates sold the naming rights to PNC Park to locally-based PNC Financial Services. Before the naming rights were sold, there was hugely popular sentiment in Pittsburgh to name the park itself after Clemente.
It is closed to vehicular traffic on Pirates' and Steelers' game days, providing a pedestrian route to PNC Park and Heinz Field. When PNC Park was built, a statue of Roberto Clemente, originally erected at Three Rivers Stadium, was placed at the southeast corner of the park, right at the north anchorage of the Roberto Clemente Bridge.
The Pittsburgh History and Landmarks Foundation in cooperation with the Riverlife Task Force, the City of Pittsburgh, and Duquesne Light Company, funded and managed the architectural lighting of the bridge. On November 20, 2002, the bridge was lit for the first time.

DAY 664

Whitehall Camp and Conference Center

© Kyle Yates Photography, 2014
ALL RIGHTS RESERVED

Backyard Brookville PA

© Kyle Yates Photography, 2014
ALL RIGHTS RESERVED

Whitehall Camp & Conference Center

© Kyle Yates Photography, 2014
ALL RIGHTS RESERVED

A snow roller is a rare meteorological phenomenon in which large snowballs are formed naturally as chunks of snow are blown along the ground by wind, picking up material along the way, in much the same way that the large snowballs used in snowmen are made.
Unlike snowballs made by people, snow rollers are typically cylindrical in shape, and are often hollow since the inner layers, which are the first layers to form, are weak and thin compared to the outer layers and can easily be blown away, leaving what looks like a doughnut or Swiss roll. Snow rollers have been seen to grow as large as two feet in diameter.
The following conditions are needed for snow rollers to form:
  • The ground must be covered by a layer of ice to which snow will not stick.
  • The layer of ice must be covered by wet, loose snow with a temperature near the melting point of ice.
  • The wind must be strong enough to move the snow rollers, but not strong enough to blow them apart.
  • Alternatively, gravity can move the snow rollers as when a snowball, such as those that will fall from a tree or cliff, lands on a steep hill and begins to roll down the hill.
Because of this last condition, snow rollers are more common in hilly areas. However, the precise nature of the conditions required makes them a very rare phenomenon.