How cloud seeding increases precipitation and why is controversial

Content of the article

(Bloomberg) — Humans began using chemicals decades ago to increase the ability of clouds to produce rain and snow, but the technology is gaining traction as climate change makes some regions hotter and drier.

Content of the article

Although popular in countries including the United States and the United Arab Emirates, cloud seeding remains controversial because it can lead to unintended consequences, such as too much rain or increased pollution.

Content of the article

Debate over climate change and control, also known as global geoengineering, has intensified because clean technologies and cutting greenhouse gas emissions have not been enough to stop global warming. Proponents argue that tackling the climate crisis is so urgent that no option should be overlooked, while opponents warn of lack of regulation, unintended side effects and delays in the energy transition.

What is cloud seeding?

Aircraft or ground-based generators stimulate existing clouds by injecting salt or silver iodide particles that form ice crystals that condense into rain or snow, depending on altitude. According to the World Meteorological Organization, seeding can increase individual cloud precipitation by up to 20% under optimal conditions.

Content of the article

Content of the article

RECOMMENDED VIDEO

Is the heavy rain in Dubai due to cloud seeding?

The UAE has been using seeding to address water security issues since 2002, although in many areas the lack of drainage can lead to flooding. The National Weather Service said the clouds were present from April 14 to April 15, but not on April 16.

On April 16, rain lashed Dubai, causing flight cancellations, traffic snarls and school closures. Some videos on social media showed cars being swept off the roads, while another showed the roof of a shop collapsing as water flooded one of Dubai's most popular malls. Flight disruptions continued at Dubai International Airport on Wednesday, with Emirates suspending passenger check-ins.

Content of the article

How effective is cloud seeding?

Cloud seeding does not work in thin air because the chemicals must be injected into existing clouds. It was successful when it targeted rain clouds in mountainous regions, in other words, when it aimed to increase rain. There is mixed scientific evidence for its effectiveness against clouds where rain may not fall, in lowland areas, and during droughts, in which some researchers suggest it becomes a political tool.

According to research cited by the nonprofit Desert Research Institute, long-term seeding projects have increased snowpack by about 10% per year in targeted areas above the Nevada Mountains in the US. Similar results have been reported in Wyoming's Snowy Range and Sierra Madre Range, as well as in the Australian Snowy Mountains.

Content of the article

RECOMMENDED VIDEO

What is the history of cloud seeding?

Cloud seeding was developed in the 1940s and became popular in the US in the 1950s and 1960s as farmers, hydropower companies, and ski resorts benefited from additional rainfall. But it fell out of favor in the decades that followed, as government funding dried up after revelations that the US used a secret military vaccination program during the Vietnam War. In 1977, the United States, Russia, India, and some European countries signed the Environmental Modification Convention, which banned military weather modification techniques.

As rapid climate change worsens the struggle for water, more countries are exploring cloud seeding. It is used in the western states of the USA and in European countries, including France and Spain. China regularly uses it for irrigation purposes and to regulate rainfall in Beijing, including during the 2008 Olympics.

Is cloud seeding dangerous?

The increased use of technology has led to the creation of a team on climate change at the World Meteorological Organization, which in a 2023 report warned of a lack of knowledge about the effects of technology.

Other concerns include changing existing weather patterns at the local level, which could lead to adverse conditions such as hail in agricultural areas. WHO experts also warn that chemicals such as silver iodide are toxic, so their use should be monitored for health and environmental impacts.

Content of the article