The phenomenon is attributed to the exhaust fumes from ships. Soot particles emitted by the ships are believed to function as nuclei for condensation, increasing the formation of water droplets.
इतक्या उंच प्रदेशातून जात असल्यामुळे या रेल्वेच्या डब्यांमध्ये कृत्रिम हवा पुरवावी लागते.