From farms and forests to wetlands
and urban areas, southern Florida packs many diverse landscapes into a
relatively small area. The dense Miami-Fort Lauderdale urban corridor
lines the Atlantic Coast with block after block of silver in this scene
acquired by the Landsat 5 satellite on November 10, 2011. The wetlands
of the Everglades fill the southwestern quadrant of the image, a
combination of muddy water (brown) and clear water (black). Green
squares in the top center portion of the image are farms, and the uneven
patches of dark green in the upper right are forests.
Viewing the scene in a different light reveals features that are difficult to see in
visible light,
such as the role of fire in managing agriculture. The image below
combines green, near infrared, and shortwave infrared light. In this
false-color band combination, plant-covered land is bright green, water
is black, and bare earth ranges from tan to pink. Newly burned farmland
is dark red, while older burns are lighter red. Much of the farmland in
this area is used to grow sugar cane. Farmers burn the crop before
harvest to remove leaves from the canes. Because burned land stands out
so vividly in this kind of false-color image, it is possible to see how
extensively farmers rely on fire in this region.
This false-color view also reveals how water flows through the Northern
Everglades. Green islands punctuate the wetlands, which are black and
blue. These are tree islands that are hard to distinguish in natural
color. Their orientation aligns with the flow of the water, highlighting
direction that is not obvious in the natural color image. It is also
easier to see the extent of the wetlands against surrounding land, since
water is dark in this view and plant-covered land is bright green. The
adjoining urban area is purple.
The third image shows the scene in green, red, and
near infrared light.
Plants are dark red because they reflect infrared light strongly, and
the infrared band is assigned to be red. That means that this type of
false-color image can help us see how well plants are growing and how
densely vegetated an area is. Plants that are growing quickly (such as
developing crops) reflect more infrared, so they are brighter red. Dense
vegetation is dark red. Patches of dark red in the upper left corner of
the image are Cyprus forest. Water is black and blue, and urban
areas—including Miami, Fort Lauderdale, and West Palm Beach—are silver.
The series of Landsat images illustrates why you might want to see the world in false color. A related
animation shows how the images were made. Read more:
Why is that Forest Red and that Cloud Blue? How to Interpret a False-Color Satellite Image.
- Instrument(s):
- Landsat 5 - TM - NASA
