Dubai uses cloud seeding to tackle dust, but why can't Delhi trigger rain to beat toxic smog?

Every winter, Delhi finds itself grappling with a familiar air pollution crisis. Air quality plunges to hazardous levels, residents struggle to breathe, and authorities scramble to introduce emergency measures to contain the worsening situation. Yet, despite successive pollution-control plans and repeated interventions, the national capital continues to struggle to find a lasting solution.

One of the measures being considered is cloud seeding, a weather-modification technique designed to induce artificial rainfall that can wash suspended pollutants out of the atmosphere.

In the aftermath of Diwali, the Delhi government is reportedly considering another round of cloud seeding trials to tackle rising pollution levels, The Indian Express reported. Two trial runs are learnt to have already been conducted near the airport.

However, this is not the first time Delhi has explored artificial rain as a possible intervention against air pollution. On October 28, 2025, the Delhi government, in collaboration with the Indian Institute of Technology (IIT) Kanpur, conducted two cloud seeding trials over the capital.

During the experiment, a small aircraft flew over parts of Delhi and released flares containing silver iodide and salt particles into the atmosphere in an attempt to trigger rainfall.

The results, however, were far from encouraging. According to The Indian Express, improvements in air quality on the day of the experiment had begun several hours before the cloud seeding operation. Pollution levels subsequently fluctuated and even rose after the trials.

Delhi received no rainfall, while Noida and Greater Noida recorded just 0.3 mm of precipitation.

Cloud seeding has also been explored in other parts of the world, particularly Dubai and the wider United Arab Emirates (UAE), where researchers have examined its potential to induce rainfall and reduce airborne dust and particulate matter.

So, what makes cloud seeding a potential intervention in the UAE, and why has Delhi struggled to achieve similar results? The answer lies largely in the science of cloud formation, atmospheric moisture and the conditions required to trigger rainfall.

What is cloud seeding and how does it work?

Cloud seeding is a weather-modification technique that involves introducing substances such as silver iodide or sodium chloride (common salt) into suitable clouds to encourage the formation of larger water droplets or ice crystals, potentially triggering precipitation.

Under natural conditions, water vapour condenses around tiny particles suspended in the atmosphere, forming cloud droplets.

These droplets collide and combine as clouds develop. As they grow larger and heavier, they eventually fall to the ground as rain.

Cloud seeding attempts to accelerate this process by introducing additional particles that act as nuclei around which moisture can condense or freeze.

The technique is generally carried out using aircraft or ground-based generators that disperse seeding agents into suitable cloud systems.

The scientific foundations of modern cloud seeding date back to 1946, when American chemist Vincent Schaefer and his colleagues at General Electric demonstrated that introducing dry ice into a supercooled cloud inside a laboratory freezer could trigger the formation of ice crystals.

Since then, several countries have experimented with cloud seeding for different purposes, including increasing rainfall, mitigating drought and influencing snowfall.

Why did cloud seeding fail in Delhi?

One of the biggest obstacles to Delhi's cloud seeding experiments has been the absence of favourable atmospheric conditions.

For artificial rainfall to occur, clouds must contain sufficient moisture, have adequate vertical development and possess the right microphysical characteristics for the seeding agents to work.

M Rajeevan, former secretary of the Ministry of Earth Sciences, had earlier explained this limitation to The Indian Express.

"Cloud seeding can only happen if there is a sufficient number of clouds and a particular depth to these clouds," he said, adding that an adequate concentration of cloud droplets was also necessary.

This presents a particular challenge in Delhi during winter. The region frequently experiences stable atmospheric conditions, temperature inversions and stagnant air, which restrict the dispersal of pollutants and allow them to accumulate close to the surface.

While pollution levels may be extremely high, that does not necessarily mean the atmosphere contains the moisture-rich clouds needed to trigger artificial rainfall.

What has Dubai achieved with cloud seeding?

The UAE has invested in cloud seeding as part of its broader efforts to address water scarcity and improve rainfall availability in an otherwise arid region.

Unlike Delhi's winter pollution-control experiments, cloud seeding in the UAE is primarily aimed at increasing rainfall in a country that receives limited natural precipitation.

Researchers have also examined whether rainfall induced through cloud seeding can help reduce airborne dust and particulate matter.

A two-year study examining atmospheric dust and sand in the UAE, published in the journal Environmental Pollution, explored the relationship between cloud seeding, rainfall and atmospheric particulate matter.

This process can temporarily improve air quality by reducing the concentration of suspended particulate matter.

The UAE's experience, therefore, cannot automatically be replicated in Delhi. The two regions have different meteorological conditions, pollution sources and seasonal weather patterns. A technique that may help induce rainfall under favourable conditions in one region may not deliver the same results in another.

Can artificial rain solve Delhi's pollution crisis?

Even if cloud seeding successfully triggers rainfall over Delhi, its impact on air quality is likely to be temporary.

Rain can wash some suspended pollutants out of the atmosphere, but it does little to address the underlying sources of pollution, including vehicular emissions, industrial activity, construction dust, waste burning and seasonal agricultural fires.

Moreover, without sustained rainfall and favourable wind conditions, pollutants can accumulate again, particularly during winter when atmospheric conditions restrict their dispersal.

This makes cloud seeding a possible short-term intervention rather than a substitute for sustained pollution-control measures.

The experience of the UAE suggests that cloud seeding may offer temporary relief from airborne particulate matter when favourable conditions produce rainfall.

But for Delhi, where winter pollution is driven by multiple sources and unfavourable meteorological conditions, artificial rain is unlikely to be a standalone answer.