Remote Sensing - Imagery in Demining
Aerial Imagery as Part of
the GIS Database
Remote Sensing and Geographic Information Systems
are two closely related fields. A GIS is a very powerful tool that
can be used for the storage, retrieval, display, analysis, linkage,
and manipulation of spatial data and tabular data. As technology
improves, Remote Sensing is becoming an integral part of this system.
The imagery provided by Remote Sensing can be used to update GIS
layers and provide a complete spatial coverage of the area of study.
This is important because updated and complete information is necessary
to provide an accurate analysis. On the other hand, the layers
in a GIS are also beneficial to the Remote Sensing field because
they supply correlative data. The photo interpreter can use the
GIS layers to provide a better analysis of the imagery.
Below is an example of what imagery can do when
used for demining purposes. The South- Eastern Europe Mine Action
Coordination Coordination Council has used Landsat imagery to show
where landmines have been placed. For more information, visit their
website at http://www.see-demining.org/main.htm.
Applications for Aerial Imagery in Humanitarian
Aerial imagery has much to offer to those involved
with humanitarian demining management. With the types of political
and physical environments faced in demining activities, updated
sources of information are crucial. The absence of accurate and
current maps often translates into an inability to effectively organize
and plan field operations. Aerial imagery can substitute for maps,
or be used to update maps. A Geographical Information System (GIS)
is a common tool to accomplish this.
Most demining missions are located in developing
nations. However, it is difficult to obtain useful land cover and
topographic information from these regions. Without the fundamental
geographic data for unfamiliar territories, demining event participants
are unprepared for travel and logistics within the mine areas. Uninformed
personnel traveling these areas are likely to encounter hazardous
conditions. Imagine planning any extensive trip to a foreign
land without consulting a map. Given these situations, aerial imagery
is a vital resource for planning demining activities.
With aerial imagery in hand, managers can efficiently
extract the precious information they need to construct maps. From
aerial photography, leaders can examine the road ahead and make
ready the proper equipment and transportation vehicles.
As you would suspect, buried mines represent
the most difficult aspect of mine detection. Therefore, many nations
are now employing the use of varying sensors to aid in the search
of landmines. A Thermal Infa-Red Scanner is being used by the United
States Army as part of the Airborne Standoff Minefield Detection
Sysstem, ASTAMIDS. The Thermal Infa-Red Scanner detects mines based
on the thermal or heat signature of a particular mine. This system
also uses a Global Positioning System (GPS) to acquire accurate
ground coordinates for the detected mine. Ground penetrating radar
and SAR are commonly used in the detection of landmines.
Hyperspectral systems employ methods to detect
where soil has been disturbed, suggesting a place where a mine has
been buried. However, Yperspectral systems are subject to the time
the mine has been buried in the ground; therefore, it becomes ineffective
after a certain period of time in mine detection. Some sensor methods
are also subject to the effects of temperature on mine detection.
During some parts of the day, mine detection is not possible due
to loss of temperature differntial necessary to detect buried mines.
The use of sensor systems is an ever-evolving
field of mine detection. The technology is consistently being improved
to better suit the needs of deminers.