Geoengineering: Reining in the weather warriors

A half-forgotten UN convention can be dusted down to mitigate tensions over modifications of climate and weather

The World Today Published 15 February 2022 3 minute READ

Tracy Raczek

Former climate advisor to the UN Secretary-General and the President of the General Assembly

While climate change has been dominating the international agenda in recent years, efforts to influence the weather and reflect solar heat have received less scrutiny despite their potential to increase regional tensions. 

Countries are increasingly using technology to change conditions in the atmosphere, oceans and ice to improve weather to their advantage or lessen global warming. However, the results of these interventions can cross borders and what may be good for one country may not be good for its neighbours. 

China plans to be able to modify weather over half its territory by 2025

This is not a hypothetical problem. Iran has already accused Israel of stealing its water by using cloud-seeding that reduces rainfall over its territory. China, which already artificially alters its weather over major cities, plans to be able to modify weather over half its territory by 2025, to the alarm of neighbours including India. And two Middle East rivals – the United Arab Emirates and Saudi Arabia – are scaling up rain-making operations.  

The best mechanism for policing such interventions can be found in a UN convention that dates back to the end of the Vietnam war. The Convention on the Prohibition of Military or Any Other Hostile Use of Environmental Modification Techniques, known as the ENMOD Convention, came into force in 1978 and has been ratified by 78 countries, including Russia, the United States, Britain, China and Germany. 

The convention was hammered out between the Cold War superpowers following ethical concerns about Operation Popeye – a classified cloud-seeding programme carried out by the US Air Force from 1967-1972 to extend the monsoon season in Vietnam and Laos so roads would be flooded, hampering Viet Cong military movements. Civilian lives, local food production and private property can be damaged or destroyed by this indiscriminate technology when used in conflict.  

As the planet rapidly warms, there is an urgent need to revisit ENMOD. The agreement states in Article I that signatories are ‘not to engage in military or any other hostile use of environmental modification techniques having widespread, long-lasting or severe effects as the means of destruction, damage or injury to any other State Party’. The ‘or’ is important. All three criteria – widespread, long-lasting, severe – need not be met and many weather- and climate-modifying technologies meet at least one criterion. 

ENMOD’s Article II outlines which environmental modification technology is covered by the convention. Here again a wide net is cast. It includes ‘any technique for changing – through the deliberate manipulation of natural processes – the dynamics, composition or structure of the earth, including its biota, lithosphere, hydrosphere and atmosphere, or of outer space’. This would cover all weather- and climate-modifying technology currently in use.  

The most ambiguous part of the convention – which needs updating and clarification – is the matter of intent. The use of this technology for military or hostile ends is strictly prohibited and violations can be referred to the UN Security Council. ‘Peaceful purposes’ are, however, allowed.

But what happens when it is used with purportedly peaceful intent yet causes harm to a neighbouring country?  

This question is all the more difficult as communities and countries look to weather modification and geoengineering to help protect themselves from the worst effects of global warming. Hostile and peaceful intended uses of this technology can become muddled.   

The technology falls, generally, into three categories with different objectives: fertilizing the ocean to increase its uptake of carbon; brightening clouds or ice to reflect more sunlight back into space and thus reduce global or local warming; or the most common technology – as seen in agricultural communities or ski resorts – of injecting aerosols into the stratosphere to increase rainfall or snow, or to modify a storm.  

Such operations are already under way in more than 50 countries, according to the World Meteorological Organization. Mexico’s Air Force, for example, has begun cloud-seeding in the past 12 months. The Arctic Ice Project, an NGO, intends to deploy small hollow glass beads, composed of silicon dioxide, across parts of the Arctic Sea’s ice and in the Arctic Ocean to increase reflectivity and slow global warming. Australian universities are piloting a salt spray over the Great Barrier Reef to reflect more of the sun’s heat in an attempt to conserve the reef.  

Scientists are plagued, however, by the complexities of understanding the technology’s direct impact and its knock-on effects. In the case of cloud brightening – a type of solar radiation management – there is uncertainty over how it might adversely affect ecological systems, agriculture and global warming.

The Intergovernmental Panel on Climate Change (IPCC) notes that cloud brightening risks depleting the planet’s ozone layer and affecting regional weather patterns, while doing nothing to reduce ocean acidification. Moreover, for cloud brightening to effectively reduce global warming, it would need to be sustained through wars, economic crashes and technological glitches. Any prolonged interruption would see global warming ricochet up. 

In the case of cloud-seeding, there is uncertainty about adverse impacts on neighbouring countries, some of which are already coping with food or water security – concerns that will grow for many as the changing climate alters the distribution, predictability and amount of precipitation.  

Three aspects of the technology’s use have particular security implications. First, the threat that its deployment in one area could affect another. Second, the difficulty in distinguishing harmful effects on neighbouring countries from insignificant ones. Last, the ease with which the technology’s use could be claimed as peaceful yet be covertly applied to harm an adversary.   

Only ENMOD is mandated to address the use of environment technologies as a weapon

As countries deploy this technology, there are questions over which international framework is best suited to control it in the context of climate and security.

The answer is ENMOD.

Other UN conventions and forums on the environment and climate, such as the UN Framework Convention on Climate Change, the UN Environment Assembly, the IPCC and the UN Biodiversity Convention are essential to address various aspects of climate change. UN bodies such as the UN Security Council, the Rome Statute of the International Criminal Court and the International Law Commission are also essential in addressing how security affects climate and vice versa.

None of these, however, are mandated to address the use of environment technologies as a weapon. Only the ENMOD Convention has this mandate. 

The timing is propitious as well. Article VIII of ENMOD requires the UN Secretary-General every 10 years to check with parties to the convention on the need to review the convention. That time is at hand.

After review failures in 2002 and 2013, the UN Secretary-General is obliged to inquire again with parties no later than 2023.  If at least 10 respond positively, the Secretary-General is required to convene a review conference.   

Secretary-General António Guterres should utilize the soft power of his office to urge parties to support a robust review of the convention. He should encourage more countries to join the convention, as ever more adopt environment modifying technology.

It is also crucial that the convention be updated to reflect a common and contemporary understanding of ‘peaceful’ and ‘hostile’ intent. 

In the face of climate change, countries need first and foremost to reduce emissions and support climate adaptation. Simultaneously, however, they need to attend to the security implications of geoengineering and weather modification. Dusting off ENMOD is the place to start.