The heavy precipitation event in Chennai, India, 1 December 2015

A fact sheet detailing a catastrophic precipitation event in Chennai, India, on 1 December 2015, and the subsequent scientific attribution analysis regarding the role of human-caused climate change.

• On 1 December 2015, Chennai experienced its heaviest one-day rainfall in over a century, with precipitation reaching up to 494 mm (19.45 inches). This event caused widespread flooding that left over three million people without basic services, damaged infrastructure, and resulted in estimated economic costs to India of US$3 bn.
• A scientific analysis by the World Weather Attribution (WWA) partnership—including Climate Central, KNMI, the University of Oxford, and IITD—found no measurable effect of human-caused emissions on the 1 December 2015 rainfall. The researchers suggest this lack of detectable signal was likely due to the masking effects of high levels of aerosol pollution over India.
• The extreme rainfall occurred during the 2015 rainy season, a period characterized by high Indian Ocean temperatures, record warm global surface temperatures, and a strong El Niño.

APA

Climate and Development Knowledge Network (2017). The heavy precipitation event in Chennai, India, 1 December 2015. https://cdkn.org/resource/heavy-precipitation-event-chennai-india-1-december-2015

Chicago

Climate and Development Knowledge Network. The heavy precipitation event in Chennai, India, 1 December 2015. 2017. https://cdkn.org/resource/heavy-precipitation-event-chennai-india-1-december-2015.

Wikipedia

{{cite report |author=Climate and Development Knowledge Network |title=The heavy precipitation event in Chennai, India, 1 December 2015 |date=27 February 2017 |url=https://cdkn.org/resource/heavy-precipitation-event-chennai-india-1-december-2015 |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{climateanddevelopmentknowledgenetwork2017heavy, author = {{Climate and Development Knowledge Network}}, title = {{The heavy precipitation event in Chennai, India, 1 December 2015}}, institution = {Climate and Development Knowledge Network}, year = {2017}, month = feb, url = {https://cdkn.org/resource/heavy-precipitation-event-chennai-india-1-december-2015}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }