Filchner-Ronne Ice Shelf
 |
The calving of A-38 off Ronne ice shelf |
The
Filchner-Ronne ice shelf is in
Antarctica bordering the
Weddell Sea.
The seaward side of the Filchner-Ronne ice sheet is divided into Eastern (Filcher) and the larger Western (Ronne) sections by
Berkner Island. The whole ice shelf covers some 430,000
km², making it the second largest ice shelf in Antarctica, after the
Ross Ice Shelf. It grows perpetually due to a flow of inland ice sheets. From time to time, when the shearing stresses exceed the strength of the ice, cracks form and large parts of the ice sheet separate from the ice shelf and continue as
icebergs. This is known as "calving".
The Filchner ice shelf is nourished primarily by the
Slessor Glacier, the
Recovery Glacier, and the
Support Force Glacier, all located east of Berkner Island. The east part of this shelf was discovered in January-February 1912 by the
German Antarctic Expedition under
Wilhelm Filchner. Filchner named the feature for
Kaiser Wilhelm, but the Emperor requested it be named for its discoverer.
The Ronne ice shelf is the larger and western part of the Filchner-Ronne ice shelf. It is bounded on the west by the base of the
Antarctic Peninsula and
Ellsworth Land. Commander
Finn Ronne, USNR, leader of the
Ronne Antarctic Research Expedition (RARE) in 1947-48, discovered and photographed a strip along the entire northern portion of this ice shelf in two aircraft flights in November and December 1947. He named it the "Lassiter Shelf Ice" and gave the name "Edith Ronne Land" to the land presumed to lie south of it. In 1957-58, the US-IGY party at
Ellsworth Station, under now Captain Ronne, determined that the ice shelf was larger than previously charted, that it extends southward to preempt most of "Edith Ronne Land." Inasmuch as Capt. James Lassiter's name has been assigned to a coast of
Palmer Land, the
Advisory Committee on Antarctic Names (US-ACAN) approved the name
Ronne Ice Shelf for this large ice shelf, on the basis of first sighting and exploration of the ice shelf by Ronne and parties under his leadership. The shelf is therefore named for
Edith Ronne, the wife of Finn Ronne.
In October
1998, the iceberg
A-38 broke off the Filchner-Ronne ice shelf. It had a size of roughly 150 times 50
km and was thus larger than
Delaware. It later broke up into three parts.
The ice of the Filchner-Ronne ice shelf can be as thick as 600
m; the water below is about 1400 m deep at the deepest point.
The Filchner-Ronne ice shelf is also known as the Ronne-Filchner ice shelf but the form Filchner-Ronne appears to be more popular.
* http://nsidc.org/data/iceshelves_images/ronne_w_loc.html - Satellite image/map of Ronne (W)
* http://nsidc.org/data/iceshelves_images/ronne_e_loc.html - Filchner (E)
