The Mexican air force has been assigned a new mission: seeding clouds in an effort to combat the prolonged drought.

The drought has affected as much as 85% of Mexico’s territory since July last year, leaving large reservoirs at exceptionally low levels, straining water resources for drinking, farming, and irrigation.

As of May 31 the area affected had declined to 72% due to rainfall in many parts of the country. However, areas facing extreme or exceptional drought conditions — located in Sonora, Chihuahua, Sinaloa, Durango, Nayarit, Colima and Michoacán —increased due to a shortage of rain.

Cloud seeding thickens clouds and increases the probability of rain by up to 15%, using an acetone solution and silver iodide, which is commonly used as an antiseptic or in photography.

The chemical, prepared by the Ministry of Agriculture, is transported by plane to clouds at 5,000 meters high.
Air force pilot Guadalupe Rojas explained the method.

“When we arrive at the area, we do a preliminary reconnaissance before starting the seeding. The type of clouds is analyzed, and once safety is guaranteed, we take an entry point and enter below the cloud. We search for any ascending currents and spread the chemical,” he said.

The process was tested last March in the San Quintín Valley, Baja California, and later in Nuevo León and Coahuila to help battle fires resulting from the drought.

Air force meteorology expert Francisco Ramírez said the operation is weather dependent. “We always need adequate weather conditions. In the case of Nuevo León there was a fire, but a cold spell helped and … [the cloud seeding] worked,” he said.

He added that the operation will continue in Sinaloa, Chihuahua and Sonora, where the drought remains prevalent.

With reports from Milenio