Despite use by at least 52 countries around the world, both the National Academy of Sciences and the American Meteorological Society doubt cloud-seeding technology’s effectiveness.
By Nancy E. Landrum
The Cessna 210 aircraft, with cloud seeding equipment. (Photo: Wikimedia Commons)
Earlier this month, Jordan, the second most water-poor country in the world, ordered more rainfall through cloud-seeding to help alleviate water shortages. Jordan’s cloud-seeding experiment followed after Russia, which last year ordered the rain to fall earlier in order to guarantee a dry day for parades and celebrations. Around the same time as Russia was manipulating its weather, California’s Tahoe Basin, desperate for extra snow for the coming ski season, ordered, well, more snow.
Cloud-seeding geoengineering, in use for more than 75 years to produce rain and snow, is a technological approach to manipulate the weather and climate. In the process of cloud-seeding or weather modification, silver iodide, potassium iodide, or solid carbon dioxide is shot into clouds by rockets, sprayed into clouds by drones or aircraft, or burned in generators atop mountains. Once inside the cloud, the chemicals freeze to create ice crystals, which turn to rain or snow that falls to the ground.
In the United States, cloud-seeding has been used for drought relief, snowfall, and rainfall across the western portion of the country. In 2015, cloud-seeding reportedly produced a 34 percent increase in the length of rainfall in Texas. These artificial rain storms allegedly covered 42 percent more land area, and the rain output was 137 percent more and produced 120,885 acre-feet of rain at a cost of less than $11 per acre-foot.
While cloud-seeding geoengineering of local weather is common, developments in the technology have extended the possibility for geoengineering use on a larger scale for climate geoengineering, or global climate control.
To combat climate change, some geoengineering technologies can capture carbon emissions and store them in the ocean or underground. Other technologies could disperse sulfuric acid or aerosol particles into the stratosphere to deflect sunlight and cool the planet. Climate engineering has not yet been tested outside the laboratory or field research.
Over 190 countries have agreed to a 2010 United Nations ban on using the climate engineering technology for large-scale climate engineering over concerns of its effect on biodiversity.
However, the U.S. was not part of the 1992 U.N. Framework Convention on Biological Diversity and has not ratified the 2010 modification. President Donald Trump has criticized the U.N. and has a draft of an executive order to defund the U.N. The American Sovereignty Restoration Act of 2017 calls for full U.S. withdrawal from the U.N.
If the U.S. is in a battle with the U.N. and is not bound by the 2010 convention banning large-scale climate geoengineering, it raises the question of what an unpredictable and impulsive administration might do.
At the Carnegie Climate Geoengineering Governance Initiative’spublic launch earlier this month, many questions were raised around climate geoengineering’s safety not just for humans and the environment, but also from nefarious individuals or governments.
China, the largest user of cloud-seeding technology to produce rain and clear skies, began using it in 2008 to prevent rainfall during the opening and closing ceremonies of the 2008 Olympics in Beijing. China used the tech again in 2009 to ease a severe drought, and claims to have increased precipitation by 180 billion cubic feet between 2006 and 2016.
But cloud-seeding does not always go as planned. In 2009, China used cloud-seeding to bring reprieve to a drought. As a result, the temperatures suddenly dropped and Beijing was blanketed in snow, in effect closing highways and causing road and air traffic delays. (There is also always the possibility of increased precipitation downwind or seeding going outside the target area.)
It’s not just a question of seeding success; it’s also one of outright effectiveness. Despite use by at least 52 countries around the world, the National Academy of Sciences and the American Meteorological Society have both stated that there is no evidence that cloud-seeding actually leads to increased precipitation.
Critics contend these climate geoengineering approaches are risky and could kill marine life, stall plant growth, damage the ozone layer, and reduce rainfall while increasing warming in other areas. These technological fixes won’t solve the problem of humans causing climate change, could give us an excuse to avoid reducing carbon emissions, and could lead to a global catastrophe.
Now, many others have reported benefits, so the jury is still out. But climate geoengineering, or the ability to control global weather, is of grave concern. There are questions about who would control technology that has the potential to change our planet and how it would be used. During the Vietnam War, the U.S.’s Operation Popeye used cloud-seeding to extend the monsoon season in Vietnam to hinder movement of enemy troops.
Strict oversight of climate geoengineering is needed. That is the reason an international rule book is in development. The C2G2 project to develop a global governance document is expected to take five years to complete.
Until then, research on global climate geoengineering will continue while countries, states, and counties buy the local weather and we anxiously watch a new administration eager to assert its power.