Source: http://www.willum.com/
(Published in Imagingnotes.com (USA) September/October issue 2000)
Eyes in the Sky: In Service of Humanity?
By Bjørn Willum, freelance journalist specializing in international
conflicts, including remote sensing, Copenhagen, Denmark
WILLUM.com - The U.S. Ambassador had a few photos in her diplomatic
bag. At first glance, the photos-depicting a field where a large hole
was being dug with an excavator and oblong objects neatly lying next to
the hole-were of little interest to the diplomatic corps. It was Aug.
9, 1995, and the U.N. Security Council was reconvening at its New York
headquarters to debate the crisis in the Balkans.
Examining the photos more closely, however, revealed that this wasn't
just a dump in the countryside. In fact, the hole was a mass grave and
the oblong objects were human bodies awaiting burial at two farms near
the Bosnian town of Srebrenica, where 7,000 Muslim men were reported missing
shortly before the photos were taken by a Pentagon U-2 spy plane.
The photos caused great upheavel in the council, as well as in the media,
and justified a much harder stance by Western governments toward the nationalist
leadership of the Bosnian Serbs. But the Srebrenica photos also proved
that overhead imagery could be used by human rights groups to combat large-scale
crimes against civilians.
Last year, another instructive project for human rights groups was carried
out involving, among others, the U.N. High Commisioner for Refugees (UNHCR),
whose staff used aerial imagery to assess damage to villages after Serbian
ethnic cleansing in Kosovo. The imagery allowed analysts to assess housing
conditions simply by counting how many houses lacked roofs, which usually
collapse if a house is burned or otherwise destroyed (Figure 1).
Of course, some houses could be severely damaged inside despite an intact
roof, but the imagery provided a good foundation for estimating available
housing, says Jean-Yves Bouchardy from UNHCR's Geographical Information
Unit, which participated in the assessment project. "The information
on the damage of villages was essential to plan the return of refugees
[and] the shelter needs for the coming winter," he says (Figure 2).
Even though the imagery was provided free of charge by various U.S.
defense institutions, 1-meter commercial satellite imagery could have
done the job as well, and for rapid damage assessment, it might even have
been cost effective to purchase the imagery, according to Bouchardy. "If
we have to send a team of experts to access all the villages, it would
be far more costly and sometimes impossible. The imagery was very useful
because some of the areas were still under fighting or there were land
mines," he says.
Human rights groups often face the same problems that Bouchardy's team
encountered: Access to scenes of heinous crimes is usually cumbersome
and dangerous. With the help of satellite imagery, analysts could substantiate
or refute news reports of systematic destruction of villages. While it
would be dangerous for a non-governmental organization (NGO) to fly a
spy plane over warring territories to look for mass graves, very high-resolution
commercial satellite imagery could, without risk, provide data to much
the same effect.
Because turned soil is a different shade of gray than undisturbed soil
on satellite imagery, comparing two images taken at different times allows
analysts to detect holes dug in the interim, provided the holes cover
more than a few square meters of ground and aren't covered by forest.
However, whether the objective is counting destroyed buildings or looking
for mass graves, satellite imagery is a complementary tool and can't provide
all the answers. First, according to Bouchardy, you must know where and
when to look; you need to know that something has happened. Next, supplementary
information must establish whether houses lack roofs due to ongoing construction
work, an earthquake, suppressive campaigns or something else.
Likewise, turned soil doesn't necessarily reveal a mass grave. Rather
it may indicate a dump or newly plowed field. Even if human bodies were
lying next to a grave when a satellite passed over, human bodies would
be extremely difficult to detect in a 1-meter resolution image. But used
with news reports or witness accounts, satellite imagery can help substantiate
allegations of atrocities and help policymakers apply pressure on reluctant
external governments to intervene diplomatically or militarily.
Satellite imagery also can be used effectively by U.N. International
Criminal Tribunals endeavoring to bring the masterminds of crimes against
humanity to justice. Instead of rushing around to check every field in
a country, prosecutors could use satellite imagery to point out a small
number of suspected sites to investigate.
Using satellite imagery to track refugee movements is another useful
application for human rights groups, because refugee flows often result
from systematic violence. In addition, the ability to keep a public eye
on refugees contributes to their safety. However, the task of tracking
refugees is hampered by the fact that it's extremely difficult to track
humans with even the best commercial satellite imagery available today,
unless, for instance, the background has an exceptionally contrasting
effect.
Therefore, to locate refugees it's necessary once again to look at circumstantial
evidence. The presence and number of refugees can be inferred by identifying
larger objects, such as tents and large campfires in unusual places or
cars in unfamiliar convoys.
Even so, efforts to combat human rights abuses will be greatly hampered
by very slow delivery times. Although Space Imaging's (Thornton, Colo.)
IKONOS satellite can provide commercial 1-meter resolution imagery to
customers within 24 hours, this is clearly the exception. Some imagery
takes longer to obtain because of cloud cover and other factors-a long
time in a world where events occur quickly and one human rights violation
is usually followed by another.
Another problem for human rights groups is imagery cost, especially
considering that NGOs often need at least a dozen images for proper assessment.
So why not rely on the U.S. government-who gave imagery away for free
on Srebrenica in 1995 and during the Kosovo campaign last year-whose equipment
is far superior to that of commercial providers?
"There's a highly selective process of releasing pictures in the
Pentagon," says Susan Osnos, associate director of Human Rights Watch
(New York). Osnos points out that the Srebrenica images were released
long after the victims were dead and buried and following a major internal
squabble in the administration. Further, NGOs have not conducted proper
testing to assess the utility of using commercial satellite imagery as
a complementary tool to monitor human rights abuses. The reason, according
to Osnos, is that even large organizations such as the Human Rights Watch
don't have large enough budgets to buy test imagery on a large scale.
The technology exists for greater information-gathering capabilities
by human rights groups. However, an atmosphere of cooperation must exist
between image providers (commercial and government) and NGOs to promote
better monitoring of human rights violations.
Captions Figure 1. Overhead images such as this can help human rights
groups monitor human rights violations. The arrow points to one of many
damaged houses. This possibly degraded U.S. military image is comparable
to 1-meter resolution commercial imagery. Credit NATO
Figure 2. This damage-assessment map summarizes UNHCR findings regarding
housing conditions in Kosovo after Serbian ethnic cleansing campaigns.
Credit UNHCR Geographical Information Unit
-------------------------------------------------------------------------
Bjørn Willum is a freelance journalist
He can be contacted by e-mail on bjorn@willum.freeserve.co.uk
Translations of some previously published articles can be found on http://www.willum.com
|