A Statistical Study on Cloud Base Height Behavior and Cloud Types During Southwest Monsoon over a High-Altitude Site in Western Ghats, India

• Published in: Journal of the Indian Society of Remote Sensing 2024, Vol.52 (1), p.203-217
• Main Authors: Leena, P. P., Mise, Dhwanit J., Resmi, E. A., Anil Kumar, V., Chakravarty, K., Nirmin, K. S., Kumar, P. Pradeep, Patil, Rohit P., Pandithurai, G.
• Format: Article
• Language: English
• Subjects: Altitude; Clouds; Earth and Environmental Science; Earth Sciences; Environmental conditions; Frequency distribution; Ground-based observation; Height; High altitude; Monsoons; Rainfall; Remote Sensing/Photogrammetry; Research Article; Seasonal variations; Variability; Wind
• ISSN: 0255-660X; 0974-3006
• DOI: 10.1007/s12524-024-01808-2

In the present work, a statistical understanding of cloud base height (CBH) behavior over a high-altitude site (Mahabaleshwar, 17.92°N, 73.66°E, and 1348 m above mean sea level) in the Western Ghats, India, has been detailed using Ceilometer measurements. The study focused on the southwest monsoon (June to September) including May and October for a period of three years 2019–2021. Cloud occurrence frequency showed clear monthly variation from May to October with maxima during the southwest monsoon. A clear altitude-temporal variability has been noticed in three level CBH detected i.e., CBH 1, 2, 3, over the study region. May and October showed lower (higher) CBH during daytime (night-time), whereas JJAS exhibited less significant diurnal variability with low values throughout the day. Monthly and seasonal variation of mean CBH (lowest layer) showed high values during May and October whereas low during the southwest monsoon season. Analysis showed the presence of layered clouds over the study region. Cloud type classification based on CBH showed a higher percentage of low and mid-level (mid-level) clouds during May (October). Low-level clouds were dominant during the southwest monsoon over the study region. Further, CBH behavior and cloud types were investigated under various environmental conditions or phases associated with the respective season/month. Distinct variations in CBH frequency distribution and cloud types are noted from the classified conditions/phases. Presented results indicated that the study region receives a good amount of rainfall mostly from the low-level clouds during the southwest monsoon, whereas low-level and mid-level significantly contribute to the total precipitation during May and October. This is the first such report using long-term ground-based observation from a high-altitude complex terrain like the Western Ghats explicitly on CBH behavior.