Petermann glacier
Encyclopedia
Petermann Glacier is a large glacier
located in North-West Greenland
to the east of Nares Strait
. It connects the Greenland ice sheet
to the Arctic Ocean
near 81 degrees north latitude. The tidewater glacier consists of a 70 km (43.5 mi) long and 15 km (9.3 mi) wide floating ice tongue whose thickness changes from about 600 m (1,968.5 ft) at its grounding line to about 30–80 m (98.4–262.5 ft) at its front. Rough mass balance estimates using these scales suggest that about 80% of its mass is lost as basal meltwater, yet little oceanographic
data are available to connect Petermann Glacier to its fjord
and adjacent Nares Strait. Even the sill depth and location is largely unknown as modern sounding
s of the fjord are still lacking.
from Petermann Glacier. A large chunk estimated to be 100 square miles (259 km²) calved off the glacier in August, 2010. The Danish Meteorological Institutes maintains an archive of imagery of Petermann Glacier and adjacent coastal areas of Greenland from both European and US satellites and sensors such as Envisat
, MODIS
, and AVHRR.
to better understand rates and mechanism by which Arctic sources of fresh water may impact the climate states of the North Atlantic. The program was continued as part of the Canadian International Polar Year projects when the CCGS Henry Larsen entered the fjord in 2007 and 2009.
In 2009, scientists aboard the Greenpeace
ship Arctic Sunrise
conducted multi-disciplinary measurements at Petermann glacier to document the anticipated detachment of a large area of the glacier to obtain insight into glacier dynamics and to highlight glacier response to ongoing Arctic climate warming ahead of the Copenhagen summit
..
satellite images
taken on August 5th; Patrick Lockerby re-posted cropped NASA images with interpretations on the internet the same day. It was largest Arctic iceberg to calve
since 1962, however, it is unclear whether the event was related to global warming
or not . The Select Committee on Energy Independence and Global Warming of the US House of Representatives held hearings on Petermann Glacier and the Greenland icesheet within days of the 2010 break-up.
The National Ice Center named the new iceberg, the Petermann Ice Island (2010) to differentiate it from a similar calving event two years earlier which produced Petermann Ice Island (2008). That island was tracked by the Canadian Ice Service
for over a year as it travelled out into Nares Strait
and south through Baffin Bay
before losing contact with the remnants in Frobisher Bay
in July 2009.
Glacier
A glacier is a large persistent body of ice that forms where the accumulation of snow exceeds its ablation over many years, often centuries. At least 0.1 km² in area and 50 m thick, but often much larger, a glacier slowly deforms and flows due to stresses induced by its weight...
located in North-West Greenland
Greenland
Greenland is an autonomous country within the Kingdom of Denmark, located between the Arctic and Atlantic Oceans, east of the Canadian Arctic Archipelago. Though physiographically a part of the continent of North America, Greenland has been politically and culturally associated with Europe for...
to the east of Nares Strait
Nares Strait
Nares Strait is a waterway between Ellesmere Island and Greenland that is the northern part of Baffin Bay where it meets the Lincoln Sea. From south to north, the strait includes Smith Sound, Kane Basin, Kennedy Channel, Hall Basin and Robeson Channel...
. It connects the Greenland ice sheet
Greenland ice sheet
The Greenland ice sheet is a vast body of ice covering , roughly 80% of the surface of Greenland. It is the second largest ice body in the world, after the Antarctic Ice Sheet. The ice sheet is almost long in a north-south direction, and its greatest width is at a latitude of 77°N, near its...
to the Arctic Ocean
Arctic Ocean
The Arctic Ocean, located in the Northern Hemisphere and mostly in the Arctic north polar region, is the smallest and shallowest of the world's five major oceanic divisions...
near 81 degrees north latitude. The tidewater glacier consists of a 70 km (43.5 mi) long and 15 km (9.3 mi) wide floating ice tongue whose thickness changes from about 600 m (1,968.5 ft) at its grounding line to about 30–80 m (98.4–262.5 ft) at its front. Rough mass balance estimates using these scales suggest that about 80% of its mass is lost as basal meltwater, yet little oceanographic
Oceanography
Oceanography , also called oceanology or marine science, is the branch of Earth science that studies the ocean...
data are available to connect Petermann Glacier to its fjord
Fjord
Geologically, a fjord is a long, narrow inlet with steep sides or cliffs, created in a valley carved by glacial activity.-Formation:A fjord is formed when a glacier cuts a U-shaped valley by abrasion of the surrounding bedrock. Glacial melting is accompanied by rebound of Earth's crust as the ice...
and adjacent Nares Strait. Even the sill depth and location is largely unknown as modern sounding
Sounding
Sounding generally refers to a mechanism of probing the environment by sending out some kind of stimulus. The term derives from the ancient practice of determining the depth of water by feeding out a line with a weight at the end....
s of the fjord are still lacking.
Satellite Imagery
A series of satellite images from 2002 through 2009 illustrate that the terminus of the glacier has advanced towards the ocean, however, several lateral rifts have developed also. The distance of this rifts or cracks back from the terminus has diminished for this time period also and may serve as a pre-cursor to natural ice calvingIce calving
Ice calving, also known as glacier calving or iceberg calving, is a form of ice ablation or ice disruption. It is the sudden release and breaking away of a mass of ice from a glacier, iceberg, ice front, ice shelf, or crevasse...
from Petermann Glacier. A large chunk estimated to be 100 square miles (259 km²) calved off the glacier in August, 2010. The Danish Meteorological Institutes maintains an archive of imagery of Petermann Glacier and adjacent coastal areas of Greenland from both European and US satellites and sensors such as Envisat
Envisat
Envisat is an Earth-observing satellite. It was launched on 1 March 2002 aboard an Ariane 5 from the Guyana Space Centre in Kourou, French Guyana into a Sun synchronous polar orbit at an altitude of...
, MODIS
MODIS
The Moderate-resolution Imaging Spectroradiometer is a payload scientific instrument launched into Earth orbit by NASA in 1999 on board the Terra Satellite, and in 2002 on board the Aqua satellite...
, and AVHRR.
Ship-Based Science Explorations 2003-2009
The US Coast Guard icebreaker "USCGC Healy" entered the fjord on August 11, 2003 to survey bottom topography, ocean currents, and ocean chemistry as part of a larger program funded by the US National Science FoundationNational Science Foundation
The National Science Foundation is a United States government agency that supports fundamental research and education in all the non-medical fields of science and engineering. Its medical counterpart is the National Institutes of Health...
to better understand rates and mechanism by which Arctic sources of fresh water may impact the climate states of the North Atlantic. The program was continued as part of the Canadian International Polar Year projects when the CCGS Henry Larsen entered the fjord in 2007 and 2009.
In 2009, scientists aboard the Greenpeace
Greenpeace
Greenpeace is a non-governmental environmental organization with offices in over forty countries and with an international coordinating body in Amsterdam, The Netherlands...
ship Arctic Sunrise
MV Arctic Sunrise
The MY Arctic Sunrise is an icebreaker operated by Greenpeace. The vessel was built in 1975 and has a gross tonnage of 949 tonnes, a length of 50 m and a maximum speed of...
conducted multi-disciplinary measurements at Petermann glacier to document the anticipated detachment of a large area of the glacier to obtain insight into glacier dynamics and to highlight glacier response to ongoing Arctic climate warming ahead of the Copenhagen summit
2009 United Nations Climate Change Conference
The 2009 United Nations Climate Change Conference, commonly known as the Copenhagen Summit, was held at the Bella Center in Copenhagen, Denmark, between 7 December and 18 December. The conference included the 15th Conference of the Parties to the United Nations Framework Convention on Climate...
..
Ice loss
In August 2010, a giant sheet of ice measuring 260 square kilometres (100 sq mi) broke off from the Petermann Glacier reducing its area and volume by about 25% and 10%, respectively. Researchers from the Canadian Ice Service located the calving from NASANASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...
satellite images
Satellite imagery
Satellite imagery consists of photographs of Earth or other planets made by means of artificial satellites.- History :The first images from space were taken on sub-orbital flights. The U.S-launched V-2 flight on October 24, 1946 took one image every 1.5 seconds...
taken on August 5th; Patrick Lockerby re-posted cropped NASA images with interpretations on the internet the same day. It was largest Arctic iceberg to calve
Ice calving
Ice calving, also known as glacier calving or iceberg calving, is a form of ice ablation or ice disruption. It is the sudden release and breaking away of a mass of ice from a glacier, iceberg, ice front, ice shelf, or crevasse...
since 1962, however, it is unclear whether the event was related to global warming
Global warming
Global warming refers to the rising average temperature of Earth's atmosphere and oceans and its projected continuation. In the last 100 years, Earth's average surface temperature increased by about with about two thirds of the increase occurring over just the last three decades...
or not . The Select Committee on Energy Independence and Global Warming of the US House of Representatives held hearings on Petermann Glacier and the Greenland icesheet within days of the 2010 break-up.
The National Ice Center named the new iceberg, the Petermann Ice Island (2010) to differentiate it from a similar calving event two years earlier which produced Petermann Ice Island (2008). That island was tracked by the Canadian Ice Service
Environment Canada
Environment Canada , legally incorporated as the Department of the Environment under the Department of the Environment Act Environment Canada (EC) (French: Environnement Canada), legally incorporated as the Department of the Environment under the Department of the Environment Act Environment...
for over a year as it travelled out into Nares Strait
Nares Strait
Nares Strait is a waterway between Ellesmere Island and Greenland that is the northern part of Baffin Bay where it meets the Lincoln Sea. From south to north, the strait includes Smith Sound, Kane Basin, Kennedy Channel, Hall Basin and Robeson Channel...
and south through Baffin Bay
Baffin Bay
Baffin Bay , located between Baffin Island and the southwest coast of Greenland, is a marginal sea of the North Atlantic Ocean. It is connected to the Atlantic via Davis Strait and the Labrador Sea...
before losing contact with the remnants in Frobisher Bay
Frobisher Bay
Frobisher Bay is a relatively large inlet of the Labrador Sea in the Qikiqtaaluk Region of Nunavut, Canada. It is located in the southeastern corner of Baffin Island...
in July 2009.