File:ISS-30 Lake Fitri, Chad.jpg

From Wikimedia Commons, the free media repository
Jump to navigation Jump to search

Original file (4,288 × 2,848 pixels, file size: 6.37 MB, MIME type: image/jpeg)

Captions

Captions

Add a one-line explanation of what this file represents

Summary

[edit]
Description
English: Lake Fitri, Chad is featured in this image photographed by an Expedition 30 crew member on the International Space Station.
  • Lake Fitri is an endorheic, or terminal lake in a desert basin in the southern Sahara Desert. Muddy yellow-brown water marks the center of the depression (center), with a ring of dark brown muds and burnt vegetation on the exposed lake floor to the north. The lake shoreline supports a thin line of reed and floating grass vegetation which appears as dark green in the image. Deserts have so little rainfall that many rivers cannot reach the sea, but end at local low points where they form lakes. Here the usually dry Wadi Batha empties into Lake Fitri. Over time, water flow in Wadi Batha has created a large delta, which occupies the entire top left third of the image—a sense of scale is given by the 23--kilometer length of the lake. The lake has been designated under the Ramsar Convention as a wetland of international importance.
  • Other features visible in the image reveal evidence of significant climate change. The dry part of the present lake shows that the lake has been larger in the last several decades. But, as NASA scientists point out, the lake was once many times larger than its present surface area, as shown by numerous sweeping curves of ancient beaches which are now situated many kilometers from the present shoreline, at higher altitudes (upper right). Inland lakes are highly sensitive to the exact equilibrium between the amount of inflow from contributing rivers like Wadi Batha and evaporation. Each beach ridge therefore shows a different lake level and thus a different balance in the lake-river-climate system.
  • A smaller river enters from the south (top right) and cuts through the beach reaches on its way to the lake. The irregular, elongated, tan patches to the west of the lake are linear dunes aligned parallel to the dominant winds which blow from the northeast. The dunes have all formed on the downwind side (southwest) side of the lake since the lake bed and delta provide the sands which have built the dunes. The dunes indicate that during past climatic phases the lake has been almost or completely dry on repeated occasions—often enough for these great dunes, many kilometers long and several meters high, to form even in the lowest parts of the lake.
  • The islands visible in the center of the lake are likewise remnants of dunes. These dunes are smaller than those on the lake margin, presumably because waves from the lake have eroded them. Villages occupy the points of some major dunes, and some islands, where fishermen can gain easy access to the lake.
Date
Source http://spaceflight.nasa.gov/gallery/images/station/crew-30/html/iss030e059398.html
Author NASA
This image or video was catalogued by Johnson Space Center of the United States National Aeronautics and Space Administration (NASA) under Photo ID: ISS030-E-059398.

This tag does not indicate the copyright status of the attached work. A normal copyright tag is still required. See Commons:Licensing.
Other languages:

العربية ∙ беларуская (тарашкевіца) ∙ български ∙ català ∙ čeština ∙ dansk ∙ Deutsch ∙ English ∙ español ∙ فارسی ∙ français ∙ galego ∙ magyar ∙ հայերեն ∙ Bahasa Indonesia ∙ italiano ∙ 日本語 ∙ македонски ∙ മലയാളം ∙ Nederlands ∙ polski ∙ português ∙ русский ∙ sicilianu ∙ slovenščina ∙ Türkçe ∙ українська ∙ 简体中文 ∙ 繁體中文 ∙ +/−

Licensing

[edit]
Public domain
This file is in the public domain in the United States because it was created by the Image Science & Analysis Laboratory, of the NASA Johnson Space Center. NASA copyright policy states that "NASA material is not protected by copyright unless noted". (NASA media use guidelines or Conditions of Use of Astronaut Photographs). Photo source: ISS030-E-59398.

العربيَّة | Deutsch | English | español | français | italiano | kurdî | македонски | മലയാളം | português | sicilianu | +/−

File history

Click on a date/time to view the file as it appeared at that time.

Date/TimeThumbnailDimensionsUserComment
current20:00, 20 April 2016Thumbnail for version as of 20:00, 20 April 20164,288 × 2,848 (6.37 MB)Ras67 (talk | contribs)new rendered in high quality from NASA's raw image data
12:46, 4 June 2012Thumbnail for version as of 12:46, 4 June 20124,288 × 2,848 (2.03 MB)Ras67 (talk | contribs)levels
17:59, 21 February 2012Thumbnail for version as of 17:59, 21 February 20124,288 × 2,848 (1.76 MB)Ras67 (talk | contribs){{Information |Description ={{en|1=Lake Fitri, Chad is featured in this image photographed by an Expedition 30 crew member on the International Space Station. Lake Fitri is an endorheic, or terminal lake in a desert basin in the southern Sahara Desert.

You cannot overwrite this file.

File usage on other wikis

The following other wikis use this file:

Metadata

This file contains additional information such as Exif metadata which may have been added by the digital camera, scanner, or software program used to create or digitize it. If the file has been modified from its original state, some details such as the timestamp may not fully reflect those of the original file. The timestamp is only as accurate as the clock in the camera, and it may be completely wrong.

Retrieved from "https://commons.wikimedia.org/w/index.php?title=File:ISS-30_Lake_Fitri,_Chad.jpg&oldid=659042898"