Remote Sensing: Wlotzkasbaken


Explanations for ETM-subsets

What kind of information is displayed?

This image is a subset of a Landsat 7 ETM+ image, covering a size of about 30 km by 25 km, which was acquired during the rainy season. It is visualized as a so-called false colour composite. On the Red, Green and Blue channels the spectral bands 4: NIR (near Infrared), 5: MIR1 (Mid Infrared 1) and 3: visible red of the Landsat ETM+ sensor are displayed (RGB: 4-5-3).This band combination suits best for a detailed visualization of different land cover properties. Due to that, the displayed colours are not natural.

Details

 Info

In the displayed image the BIOTA observatory is given as a dotted rectangular box of 1km x 1km extension. 

 View Observatory

Wlotzkasbaken 

 WRS2 Path-Row

180-75 

 Acquisition Date

22.04.2003 

 Image Details

The observatory is located in the Central Namib Desert, North of Swakopmund. Even though no higher vegetation appears in this region, the satellite signal indicates photosynthetic activity (green tones). The reason is a dense coverage with lichen fields. They are exposed to alterations by several natural destructive forces like wind abrasion and rill erosion by flooding after exceptional thunderstorms. 

In general, the colours refer to the following land cover types:

  • Dark Blue: Water bodies, dams and lakes without Algae.

  • Light Blue: in populated places mainly buildings, outside of towns mainly rocks, and very sparsely vegetated soils.

  • Red: Very dense and vital vegetation like bush thickets, forests or planted fields, in towns: gardens.

  • Green: "middle dense" or less vital vegetation, like grass savanna (light green) and dry bush (dark green).

  • White: bare soil or sparsely vegetated areas, independently from the natural soil colour, also gravel roads and pads.

  • Intermediate colours are representing mixed pixels with information of several land cover types.

E-Mail to Manfred Keil (subproject leader)