New Tech Uses Drones For Cloud Seeding
D
esigned to potentially help droughtplagued regions, a new technology uses
unmanned aerial vehicles — also known as
drones — to put more water into the clouds.
When you think of drones, you probably think of
military ones but if the Desert Research Institute
in Reno, NV has its way, drones may soon have
more to do with water than the military.
The Institute is working on a drone to promote
precipitation. Piloted planes have already been
used for this purpose, which is known as "cloud
seeding."
For over 60 years piloted planes as well as
ground bases have been used to spray silver
iodide particles into passing clouds to squeeze
more precipitation from the atmosphere, a
practice which has typically resulted in about
10% more rain. The Institute’s Meteorologist
Jeff Tilley explained that this is the first time
drones have been used for the same process.
Compared to the plane mission, the process of
the seeding itself will not drastically change,
Tilley explained. Some changes will have to be
made to the size of the seed flares due to the
compact size of the drone versus a manned
aircraft. Planes can produce an additional one
billion gallons of water for every 25 to 45 hours
in flight, but manned aircraft need to stay above
the clouds for safety reasons, according to
aviation regulations.
Drones are the perfect size and shape to
support this process.
"The smaller size of the drones, and the fact
they are not manned, provides potential
opportunities for drones to fly below the
cloud base and seed there as well as at cloud
top," Tilley said, per the report. “Drones
can fly through the clouds and can stay aloft
longer, producing even more precipitation for
communities devastated by drought.” This new
technology could reduce cloud-seeding costs by
half, since it does not include steep piloting and
fuel costs, like planes do.
Cloud seeding has become increasingly
widespread. Once viewed by some as a
fringe science, cloud seeding has entered
the mainstream as a tool to pad the state’s
crucial mountain snowpack. New technology to
manage the practice, and research that points
to reliable results, have cemented cloud seeding
as a dependable and affordable water-supply
practice.
A major test of cloud seeding, conducted
last year, revealed mixed results about its
effectiveness. The experiment was one of the
longest-running and most rigorous tests yet
of ‘cloud seeding’. An independent team of
scientists now says that it worked — sort of
according to the magazine, Nature.
"Seeding the clouds squeezed 5–15% more
precipitation out of them,” says Roy Rasmussen,
a meteorologist at the National Center for
Atmospheric Research (NCAR) in Boulder,
Colorado, who led the evaluation team. But that
statistic holds only if scientists eliminate parts
of the test that went wrong, such as when the
silver iodide spray did not completely cover the
mountain range that the researchers were trying
to seed the report said.
In 70s and early 80s rockets generating highheat at explosion were used in the Eastern
European Countries to transform potential hail
clouds into rain and it worked well saving many
agricultural fields from a hail disaster. However,
there was a danger that rockets may fall on the
ground to explode.
FARMERS GAZETTE
November 2015
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