In Search of a Drought-Proof Source - The Ripple Effect: The Fate of Freshwater in the Twenty-First Century - page 283

Phoenicians, many of them from snowbelt states, insist on artificial lakes, green
lawns and golf courses, shopping malls kept at arctic temperatures, and other resource-
intensive methods of beautification. One of the most popular cooling methods for res-
taurants, shopping centers, and even homes is to use outdoor misting systems , which
create a light fog on patios. (Misters are popular in other desert cities, most notably
Palm Springs, California.) A typical home misting nozzle uses about one to fifteen gal-
lons of water per hour, equivalent to running a large load of laundry. But a fifty-foot
misting system on a restaurant patio might consume as much as fifteen hundred gallons
of water per night, which is equivalent to a week's worth of water for a household of
two. It is so hot in Arizona that water misted during the day “flash evaporates” almost
immediately. The state does not regulate misters , though there are “plans” to ban them
in case of severe water shortage.
Arizona doesn't know exactly how much groundwater it has, or how fast it is being
used, and, according to the Bureau of Reclamation, it could face a water crisis by 2025 .
With a glint in his eye, Guenther disputed that assessment and said that while he
was concerned about climate change, he fully expected man to engineer himself out of
trouble “as we always have in the past.” He believes that by refining existing technologies
such as “weather modification” and desalination, we already have drought-proof water
sources in hand. People have used these technologies for years, but results have been
mixed, and skeptics question whether they are worth the effort.
TURNING THE RAIN ON AND OFF
I will give you rain in due season, and the land shall yield her increase, and the
trees of the field shall yield their fruit.
—Leviticus
When rain falls from clouds, it does not always arrive when and where it is useful to
man. But what if we could control the weather and produce rain whenever we like? This
question has consumed people for years.
Meteorology was considered a black art until the nineteenth century, when James
Pollard Espy , aka the Storm King, transformed it into an empirical science. Through
careful study of weather, he developed a convection theory: air rises as it heats, expands,
then cools; water vapor condenses in the clouds, then falls to earth as rain, snow, sleet,
or hail. Espy believed that he could summon rain on command and tried to convince