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Posts tagged Great Sandy Desert

Flora and Vegetation Index of the Kimberley Region, Western Australia

April 19th, 2010 Category: Vegetation Index

Australia - March 5th, 2010

Australia - March 5th, 2010

The Kimberley is one of the nine regions of Western Australia. It is located in the northern part of Western Australia, bordered on the west by the Indian Ocean, on the north by the Timor Sea, on the south by the Great Sandy and Tanami Deserts, and on the east by the Northern Territory.

This more arid geography to the south is mirrored in this FAPAR image:  southern areas appear yellow, indicating low photosynthetic activity, while coastal areas appear green, thus showing a good vegetation index.

With regards to flora, much of the Kimberley is chiefly covered in open savanna woodland dominated by low bloodwood and boab trees with Darwin stringybark and Darwin woollybutt eucalypts in the wetter areas.

The red sandy soil of the Dampier Peninsula in the south is known for its characteristic pindan wooded grassland while in the more fertile areas like the Ord valley the trees are grasslands of Chrysopogon, Aristida, Dicanthium and Xerochloa (rice grass) in the wetter valleys.

The banks of the Ord, Fitzroy and other rivers are home to a greater variety of vegetation while in sheltered gorges of the high rainfall north there are patches of rainforest. There are also areas of mangrove in river estuaries where the coast is flatter.

Multi-Braided Channels Leading to Lake Gregory, Australia – April 16th, 2010

25.6S 120.0E

April 16th, 2010 Category: Image of the day, Lakes, Rivers

Australia - March 5th, 2010

Australia - March 5th, 2010

Lake Gregory (green, lower left quadrant) is an inland drainage lake situated in northeastern Western Australia between the Great Sandy Desert and the Tanami Desert. It is usually fresh water, but can become saline after a number of dry years. The surrounding landscape consists of grasslands with numerous sand ridges.

It has a fairly regular inflow of water and is considered to be a permanent lake, serving as a major migratory stop-over area for a variety of shorebirds. The lake also provides a major breeding habitat of several species of water birds, including cormorants and terns.

Here, multi-braided channels can be seen feeding water into into Lake Gregory. These channels are part of the Sturt Creek drainage system. When there is an excess of standing water in the channels, they take on a tan or yellow, muddy-looking appearance, generally north and west of the main part of the lake. In this image, however, there does not appear to be much excess water in the channels.

Lake Gregory is situated on the edge of Mulan Aboriginal Community, home to the Walmajarri people. The lake is a traditional site to the people, housing a number of significant cultural locations. The Paraku IPA (Indigenous Protected Area) works with traditional owners and rangers to monitor and maintain the lake and its surroundings.

Lakes Dora and Disappointment by the Great Sandy and Gibson Deserts, Australia

23.4S 122.8E

March 7th, 2010 Category: Lakes, Rivers, Salt Flats

Australia - February 24th, 2010

Australia - February 24th, 2010

Two ephemeral lakes are visible in this image of arid Western Australia. The larger of the two, Lake Disappointment, appears as a white salt flat near the center. The other, smaller body of water, Lake Dora is located to the North, occasionally fed by the Rudall River.

The surrounding desert terrain is part of the Great Sandy and Gibson Deserts. The Great Sandy Desert is a 360,000 km2 (140,000 sq mi) expanse in northwestern Australia. It is a flat area between the rocky ranges of the Pilbara and the Kimberley.

To the southeast is the Gibson Desert, which is about 155,000 square kilometres (60,000 square miles) in size. It lies between Lake Disappointment and Lake Macdonald along the Tropic of Capricorn. The Gibson bioregion includes extensive areas of undulating sand plains and dunefields, low rocky/gravelly ridges and substantial upland portions with a high degree of laterite formation.

Tropical Cyclone Laurence (06S) Makes Landfall in Australia

14.2S 128.8E

December 15th, 2009 Category: Tropical Storms

Tropical Cyclone Laurence (06S) - December 13th, 2009

Tropical Cyclone Laurence (06S) - December 13th, 2009

Track of TC 06S - December 14th, 2009 © Univ. of Wisconsin

Track of TC 06S

Enhanced image

Enhanced image

Tropical Cyclone Laurence (06S) tracked through Darwin Australia this weekend before sliding back into the Timor Sea and is now forecast to make a second landfall in Australia. The storm is forecast to make landfall north of Wyndham in the Kimberley region, then parallel the coastline while moving over land for the next couple of days, heading southwest through the northern area of the Great Sandy Desert and into the Pilbara region.

Laurence is currently located approximately 250 nautical miles west-southwest of Darwin, Australia, and has tracked westward along the northwestern periphery of the mid-level subtropical steering ridge at 6 knots over the past six hours. Maximum significant wave height is 14 feet.

Upper-level analysis indicates the system is near the subtropical ridge axis and animated water vapor imagery shows good poleward and equatorward outflow. Accordingly, the system has intensified over the last 6 to 12 hours and an AMSR-E microwave image shows tightly wrapped banding and a microwave eye. Wyndham radar imagery also shows the wrapping convection and apparent low level circulation center, confirming the position.

TC 06S is expected to continue tracking generally west-southwestward along the northwestern coast of Australia throughout the forecast period. In the near term, an approaching mid-latitude trough will pass to the south but enable the steering ridge to remain oriented north-south, allowing the system to begin tracking south-southwestward over the next 24 hours.

By TAU 48, however, the system should weaken slightly as it interacts over land and it will turn more westward as a lobe of the steering ridge builds more southwestward. After TAU 96, the system should track back over very warm water and begin to re-intensify under favorable environmental conditions.

Colors of Lake Mackay, Western Australia

22.5S 128.6E

November 26th, 2009 Category: Lakes

Australia - November 24th, 2009

Australia - November 24th, 2009

Lake Mackay is one of hundreds of dry lakebeds scattered throughout Western Australia and the Northern Territory. In addition to the lake, the image also shows the dry appearance of Western Australia’s Great Sandy Desert, Gibson Desert, and Tanami Desert.

Lake Mackay measures approximately 60 miles (100 kilometers) east-west and north-south. The lake is the largest in Western Australia and has a surface area of 3,494 square kilometres (1,349 sq mi).

In this arid environment, salts and other minerals are carried to the surface through capillary action caused by evaporation, thereby producing the white reflective surface.

The darker, greyish areas of the lakebed are indicative of some form of desert vegetation or algae, some moisture within the soils of the dry lake, and the lowest elevations where pooling of water occurs.

The orange dots, on the other hand, are hills scattered across the eastern half of the lake and east-west-oriented sand ridges south of the lake.