Association of Cloud Bursts with Forest Fires

Association of Cloud Bursts with Forest Fires

Subject : Geography

Context : Recently, the scientists from Hemvati Nandan Bahuguna (HNB) Garhwal University and IIT Kanpur jointly measured the association of cloud bursts with forest fires.

Concept :

• The study has found a connection between the formation of the tiny particles, the size of a cloud droplet on which water vapor condenses leading to the formation of clouds and forest fires.
• The quantity of such particles called the cloud condensation nuclei (CCNs) were found to have peaks associated with forest fire events.
• The study measured the activation of cloud condensation nuclei and studied its impact on high altitude cloud formation and complexity of local weather phenomenon.
• The CCNs were measured by a droplet measurement technology’s (DMT) CCN Counter at Himalayan Clouds Observatory (HCO), Garhwal University.
• The observation was carried out under a Climate Change Programme Division, Department of Science & Technology (DST) funded project.

Association of Cloud Bursts with Forest Fires

• It showed that the highest concentration of CCN was found to be associated with excessive fire forest activities of the Indian subcontinent.
• The CCN concentration (CCN) was observed at four supersaturation levels (SS: 0.2, 0.5, 0.8, and 1.0%).
• The highest CCN concentration is observed at the time of sunrise and after the sunset for the diurnal variation of monsoon, post-monsoon, and winter season.
• The possible reasons for maximum concentration in morning and evening time could be upliftment and settlement of CCN because of the convection process, anthropogenic emission, vehicular emission, and biomass burning in the residential area and valley region.
• The lowest value of CCN concentration corresponds to the heavy rains and snowfall days, possibly caused by extensive wet scavenging.

Cloud Condensation Nuclei (CCN)

• The CCNs are small particles typically 0.2 µm, or 1/100 the size of a cloud droplet on which water vapor condenses.
• It can activate and grow into fog or cloud droplets in the presence of supersaturation (SS).
• It is used in cloud seeding, which tries to encourage rainfall by seeding the air with condensation nuclei.