{"id":21407,"date":"2025-10-31T13:07:48","date_gmt":"2025-10-31T07:37:48","guid":{"rendered":"https:\/\/www.aqi.in\/blog\/?p=21407"},"modified":"2025-10-31T13:11:58","modified_gmt":"2025-10-31T07:41:58","slug":"delhi-air-pollution-cloud-seeding-failure","status":"publish","type":"post","link":"https:\/\/www.aqi.in\/blog\/delhi-air-pollution-cloud-seeding-failure\/","title":{"rendered":"Flawed Cloud Seeding Attempt in Delhi – What is the concept and why did it not work out"},"content":{"rendered":"\n

On 28th October, 2025 the authorities in <\/span>Delhi NCR<\/b> in collaboration with IIT Kanpur, began <\/span>seeding clouds<\/b> as a response to the alarming poor quality of air to induce artificial rain and bring down pollution levels in the capital but it turned out to be an <\/span>unsuccessful attemp<\/b>t due to lack of pre-existing moisture in the clouds.<\/span><\/p>\n

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The Cessna aircraft was sent out on <\/span>Tuesday afternoon<\/b> in<\/span> two phases<\/b> to disperse <\/span>salt-based silver iodide flares<\/b> and seed the clouds covering areas around<\/span> Burari, Khera, Mayur Vihar, Karol Bagh <\/b>and neighbouring sites.<\/span><\/p>\n


But due to minimal moisture in the clouds, little to no rain was seen. Although, the efforts did help in <\/span>reducing the particulate matter concentrations<\/b> temporarily to some extent and further gave important insights regarding the required optimal conditions for successful trials in the future .<\/span><\/p>\n

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What is Cloud Seeding?<\/span><\/h2>\n\n\n\n

Cloud seeding is a process of altering or <\/span>enhancing a cloud\u2019s natural ability to produce rain<\/b> by introducing particles, like silver iodide mixed with sodium chloride or other salt-based compounds, into moisture filled clouds.<\/span><\/p>\n


These particles are dispersed through an aircraft to supercooled clouds, and act as nuclei and condense smaller cloud droplets into larger raindrops, giving a nudge to the rain-making process, thus <\/span>leading to artificial rain<\/b>.<\/span><\/p>\n

The <\/span>essential requirements<\/b> for a successful attempt are:<\/span><\/p>\n

    \n
  1. Cloud Presence<\/b>: The skies above target sites shouldn’t be clear.<\/span><\/li>\n
  2. Enough moisture in the clouds<\/b>:A minimum of 50%-60% relative humidity is required.<\/span><\/li>\n
  3. Appropriate cloud temperature<\/b>: The clouds need to be at temperatures around\u00a0 -5\u00b0C or colder.<\/span><\/li>\n<\/ol>\n

    \u00a0<\/p>\n\n\n\n

    \"\"<\/p>\n

     <\/p>\n\n\n\n

    Why did the Attempt fail and what is the Plan of Action now?<\/span><\/h2>\n

    Rain was expected after 20-30 minutes of not one but two cloud-seeding attempts but this did not happen due to <\/span>low moisture content(15%-20%) in the clouds<\/b> which is much lesser than the <\/span>minimum of 50%<\/b>.These required conditions are hard to meet during the current winter-transitioning weather in Delhi NCR.<\/span><\/p>\n

    9-10 such trials were scheduled over 28-30th October which have now been <\/span>put on hold <\/b>until the conditions are favourable again.<\/span><\/p>\n

     <\/p>\n\n\n\n

    Why the Cloud Seeding Attempt wasn\u2019t completely in vain<\/span><\/h2>\n

    Even though little to no rain came out of the cloud seeding trials, it cannot be considered as a complete failure.<\/span><\/p>\n

    The below graph (data source: AQI.in) gives notable insights about the PM levels.<\/span><\/p>\n\n\n\n

    \"\"<\/p>\n

    The stations included for analysis are<\/span> ITI Jahangirpuri, Mayur Vihar and Karol Bagh, <\/b>some of the few areas where the impact of cloud seeding would be expected to be more pronounced.<\/span><\/p>\n

      \n
    1. Observing the trend during the afternoon of 28th October, there is <\/span>a significant dip<\/b> in the particulate matter (PM10 and PM2.5) concentrations as compared to the trends before and after.<\/span><\/li>\n
    2. Data shows about 15-18% improvement in PM2.5 levels and <\/span>17-19% improvement <\/b>in PM10 levels post cloud-seeding trials.<\/span><\/li>\n
    3. The rise in PM levels the next day, when the trial was scheduled but did not take place, shows that even <\/span>a \u201cflawed\u201d attempt helped <\/b>with the improvement of air quality.<\/span><\/li>\n
    4. It also shows that the <\/span>impact is rather short lived <\/b>and multiple trials are required to actually see an impactful difference.<\/span><\/li>\n<\/ol>\n\n\n\n

       <\/h2>\n

      Effects and Long-Term Limitations<\/span><\/h2>\n

      A successful attempt would help reduce the air pollution by a significant amount making the air more breathable and less toxic. It would help <\/span>disperse the smog, haze and particulate matter<\/b> suspended in the air which would help calm down the deteriorating air quality, a matter of top priority right now in Delhi NCR.<\/span><\/p>\n

      There are however certain concerns regarding<\/span> chemical accumulation <\/b>in the atmosphere and <\/span>ecological disruptions<\/b> which can impact the ecosystem negatively in the long run if not taken care of or regulated during the procedure. Another limitation of this is being extremely <\/span>condition-dependent <\/b>– it is not a guaranteed rain switch as it requires very specific conditions to actually work.<\/span><\/p>\n

       <\/p>\n\n\n\n

      Conclusion <\/span><\/h2>\n

      The recent cloud seeding experiment in Delhi, though did not yield the desired rainfall, it definitely did give <\/span>valuable insights<\/b> regarding the <\/span>existing atmospheric conditions<\/b> and potential improvements in planning the future trials.<\/span><\/p>\n

      Insights suggested that even <\/span>partial technological interventions<\/b> in this sector offered some, even though short-lived, relief from the toxic air.<\/span><\/p>\n

      With insights from these trails and <\/span>more careful future deployment<\/b>, we can very much expect this to be a success story, helping the capital in its battle with air pollution.<\/span><\/p>\n

       <\/p>\n\n\n","protected":false},"excerpt":{"rendered":"

      On 28th October, 2025 the authorities in Delhi NCR in collaboration with IIT Kanpur, began seeding clouds as a response…<\/p>\n","protected":false},"author":30,"featured_media":21408,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[18,167,50,5032,5009,5023,5043,4555,5051,5026,5044,5027,5046,5048,5039,5045,5020,5050,5047],"class_list":["post-21407","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-air-pollution","tag-air-pollution","tag-air-pollution-in-india","tag-air-quality-index","tag-air-quality-management","tag-aqi-delhi","tag-cloud-seeding-in-delhi","tag-delhi-air-pollution-2025","tag-delhi-air-quality","tag-delhi-air-quality-index-today","tag-delhi-artificial-rain-attempt","tag-delhi-artificial-rain-project","tag-delhi-pollution-2025","tag-delhi-smog-control-attempt","tag-delhi-weather-modification-experiment","tag-delhi-winter-pollution","tag-failed-cloud-seeding-delhi","tag-iit-kanpur","tag-stubble-burning-impact-delhi","tag-why-cloud-seeding-failed-in-delhi"],"_links":{"self":[{"href":"https:\/\/www.aqi.in\/blog\/wp-json\/wp\/v2\/posts\/21407","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.aqi.in\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.aqi.in\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.aqi.in\/blog\/wp-json\/wp\/v2\/users\/30"}],"replies":[{"embeddable":true,"href":"https:\/\/www.aqi.in\/blog\/wp-json\/wp\/v2\/comments?post=21407"}],"version-history":[{"count":6,"href":"https:\/\/www.aqi.in\/blog\/wp-json\/wp\/v2\/posts\/21407\/revisions"}],"predecessor-version":[{"id":21447,"href":"https:\/\/www.aqi.in\/blog\/wp-json\/wp\/v2\/posts\/21407\/revisions\/21447"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.aqi.in\/blog\/wp-json\/wp\/v2\/media\/21408"}],"wp:attachment":[{"href":"https:\/\/www.aqi.in\/blog\/wp-json\/wp\/v2\/media?parent=21407"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.aqi.in\/blog\/wp-json\/wp\/v2\/categories?post=21407"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.aqi.in\/blog\/wp-json\/wp\/v2\/tags?post=21407"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}