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Posts tagged Nuclear test site

Former Novaya Zemlya Nuclear Test Site, Russia – May 17th, 2009

73.6N 56.0E

May 17th, 2009 Category: Image of the day

Russia - May 13th, 2009

Russia - May 13th, 2009

Russia’s Novaya Zemlya  archipelago lies in the Arctic Ocean in the north of Russia and the extreme northeast of Europe at Cape Zhelaniya. Due to its geographical location, it has a very severe climate.

It consists of two major islands, separated by the narrow Matochkin Strait, and a number of smaller ones. The two main islands are Severny (northern) and Yuzhny (southern). Novaya Zemlya separates the Barents Sea from the Kara Sea. The archipelago’s total area is about 90,650 km².

As Novaya Zemlya was a sensitive military area during the Cold War years, the Soviet Air Force maintained a presence at Rogachevo air base on the southern part of the island. It was used primarily for interceptor aircraft operations but also provided logistical support for the nearby nuclear test area.

In July 1954, the archipelago was designated the Novaya Zemlya Test Site, which existed during much of the Cold War. Tests occurred throughout the islands, with an official testing range covering over half of the landmass.

Over its entire history as a nuclear test site, Novaya Zemlya hosted 224 nuclear detonations with a total explosive energy equivalent to 265 megatons of TNT. For comparison, all explosives used in World War II, including the detonations of two U.S. nuclear bombs, amounted to only two megatons.

In 1961 the northern island was the explosion site of Tsar Bomba, a record 50-megaton blast conducted in the atmosphere. In 1963, the Limited Test Ban Treaty outlawing most atmospheric nuclear tests was implemented.

However, underground testing continued, with the largest underground test at Novaya Zemlya taking place on September 12, 1973. This test involved four nuclear devices of 4.2 megatons total yield. Although far smaller in blast power than the Tsar Bomba and other atmospheric tests, the confinement of the blasts underground led to pressures rivaling natural earthquakes. In the case of the September 12, 1973, test, a seismic magnitude of 6.97 on the Richter Scale was reached, setting off an 80 million ton avalanche that blocked two glacial streams and created a lake 2 km in length.

In 1988–1989, glasnost helped make the Novaya Zemlya testing activities public knowledge, and in 1990 Greenpeace activists staged a protest at the site. The last nuclear test explosion was in 1990 (also the last for the entire Soviet Union and Russia).

However, the Ministry for Atomic Energy has performed a series of subcritical underwater nuclear experiments near Matochkin Shar each autumn since 1998. These tests reportedly involve up to 100 g of weapons-grade plutonium.

Salt Fields in Former “Wandering” Lake Lop Nur, China – May 13th, 2009

40.2N 90.6E

May 13th, 2009 Category: Climate Change, Image of the day

Lake Lop Nur, China - May 1st, 2009

Lake Lop Nur, China - May 1st, 2009

ASAR image of Lop Nur - May 11th, 2009

ASAR image of Lop Nur - May 11th, 2009

This area between the Taklamakan (left) and Kuruktag (right) deserts in China, was once the location of Lake Lop Nur.

Now, all that remains of this former saline lake is a salt-encrusted lake bed, visible as a curved indentation in the center of the main image.

Lop Nur earned the nickname of “The Wandering Lake” as it used to change greatly in size and position, depending on the balance between rainfall water yield and evaporation. In the 1950s, the lake occupied roughly 2,000 square km (770 square miles).

Salt fields - MERIS image

Salt fields - MERIS image

However, the lake ceased to exist by about 1970, due to climate change and human exploitation of water resources for agriculture, particularly after irrigation works and reservoirs were completed on the middle reaches of the Tarim River, one of its former tributaries.

Salt fields - ASAR image

Salt fields - ASAR image

The close-ups focus on a salt field and salt refining facility constructed in the lake bed in 2002. The ASAR image is sharper as it is magnified by a factor of three, while the color MERIS image by a factor of five.

The bluish color of the salt fields in the MERIS image indicates the presence of water. As many salt rocks remain in the dried-up lake, salt could be refined by the wet-mining (dissolving mining) or gushing-well methods.

Between 1964 and 1996, the area was also used as a nuclear test site, with 45 underground and atmospheric nuclear tests conducted in that period. The first Chinese nuclear bomb test, codenamed “596”, was carried out at Lop Nur in 1964. The first Chinese thermonuclear detonation was performed there on December 27, 1968.