Investigation of cloud characteristics over a high-altitude region, Mt. Abu, using ground-based Lidar and satellite observations

Clouds are critical in shaping local weather patterns, particularly in mountainous regions where complex environmental factors influence their behavior. This study provides a comprehensive analysis of cloud properties over Mt. Abu (24.59° N, 72.71° E, ~ 1219 m a.m.s.l), a high-altitude region in the Aravalli Range of Western India, utilizing ground-based Lidar and satellite datasets. The study found an annual cloud occurrence of approximately 23% from January to December 2023. The seasonal mean cloud occurrence was highest during the monsoon (42.88%), followed by pre-monsoon (19.25%), post-monsoon (7.28%), and winter (4.1%) seasons. The cloud frequency peaked in the afternoon (13:00–15:00 LT) during the monsoon, exceeding 60% in July and August. In contrast, the pre- and post-monsoon periods showed moderate midday peaks (~ 25%), while winter months exhibited minimal diurnal variation with cloud occurrence generally below 10%. The seasonal mean cloud base height (CBH) was lowest during the monsoon (780 ± 1370 m) and highest in winter (4620 ± 2390 m). Shallow boundary layer clouds, confined below 2 km, were commonly observed in the pre-monsoon and monsoon seasons. Low-visibility events (vertical visibility < 100 m), primarily mist, were most frequent during July (21.5%) and August (36.8%), while winter fog events were less frequent and driven by radiative cooling under stable boundary layer conditions. MODIS observations indicated a predominance of cirrostratus clouds (~ 30%) during satellite passes, and notable discrepancies were observed between MODIS-derived CBH and Ceilometer observations. This study highlights the complex cloud dynamics in mountainous environments and underscores the need for continuous, high-resolution observations to improve cloud representation in weather and climate models.