Can man-made rain solve global drought? The truth behind the Dubai experiment

High above the Dubai desert, manned aircraft are firing chemicals into the clouds in an attempt to enhance the country’s rainfall.

The project was credited with causing a monsoon-like downpour in the drought-stricken United Arab Emirates this week.

The UAE’s weather bureau told Gulf News that cloud seeding operations were helping to enhance rainfall in the region.

Images issued by the Gulf nation’s weather bureau showed pounding rain on roads in the city of Al Ain, and warnings were issued for drivers to take care as highways were engulfed in flash flooding.

In a country that typically has gets around four inches of rain a year, wet weather tires aren’t normally required.

The unseasonal rainfall this week over the United Arab Emirates appears to have confirmed that the cloud seeding operations in the country is paying dividends.

This rainmaking technology has been around since the 1940s.

Usually referred to as cloud seeding, these involved aircraft or cannons firing solid particles, usually salt or silver iodide, into clouds to encourage snow and rainfall in dry countries.

First developed by scientists at GE in the 1940s, cloud seeding was later experimented with as a potential weapon of war by the US military.

It was also used to break a drought that threatened to cripple New York City in 1949.

That year a Harvard research meteorologist named Wallace Howell was hired to implement the cloud seeding technology.

One hundred pounds of dry ice was loaded into an NYPD twin-engine Grumman Goose and dropped into clouds over the Catskills during a flight in April 1950.

Howell took several more flights to drop dry ice into the clouds above upstate New York, and the experiment seemed to increase rainfall in the area, though conclusive results were difficult.

Cloud seeding has been used to try to halt the US’s declining snowpack, and it was hoped it could help alleviate the extreme drought currently affecting 11 western US states.

The Scientific American reports that eight states are currently using the cloud seeding technology.

In the Colorado River Basin, cloud seeding operations funded to the tune of $1.5 million annually by a combination of state agencies, utility companies and private companies.

States such as Nevada, California, New Mexico and Arizona who also stand to benefit from increased rainfall contribute to the cost.

There is evidence that cloud seeding increase rainfall by 10-15%.

However, there are drawbacks. Shooting silver iodide into clouds can be toxic to marine life.

A 2016 study found a potential risk of acute toxicity from cloud seeding on soil and freshwater.

There are also concerns cloud seeding could simply be taking rain from another location.

Similarly, desalination can cause water temperature to increase and disrupt marine environments.

Clean freshwater is especially an issue in the Middle East and North Africa, where Saudi Arabia in particular has invested billions in the energy-intensive process of extracting salt from the sea.

A 2018 United Nations study found there were almost 16,000 desalination plants operating in 177 countries, that produced the equivalent of half of the daily freshwater flow over the Niagara Falls.

However, it found that the toxic brine produced by the desalination process was usually dumped in the sea, and risked contaminating food chains if left untreated.

A new experimental form of rain enhancement is also set to be trialled in the UAE.

Drones carrying high-tech sensors to measure temperature and humidity circle the skies.

The six-and-a-half feet wide mechanical birds of prey are on the hunt for clouds to zap with an electrical charge from their on-board emitters.

Their payload should theoretically make the small cloud droplets attract one another, merging and growing until they turn into rain drops large enough to withstand the fall to earth.

The climate crisis is driving weather patterns to greater extremes, threatening a number of regions with water shortages.

According to the World Health Organization, water scarcity impacts 40 per cent of the world’s population, and “as many as 700 million people are at-risk of being displaced as a result of drought by 2030.”

In Eastern Africa, a dispute over an enormous mega dam project on the Nile river has led to increasing tension between Egypt, Ethiopia and Sudan.

Presumably, every drought-threatened country the world over will be watching the UAE study with great interest.

Firing clouds with electrical currents could be just the tonic for a drying planet.

The originally piece incorrectly referred to the use of a project from the University of Reading that used electrical currents to enhance rainfall.