That terrible water-drinking sea fire called Vadava has the tendency to go upwards and hence it is called Urdhvabhaga, It stands in the Prana.
वडवाग्निः पिबत्यम्भो योऽसौ परमदारुणः। ऊर्श्वभागूर्ध्वभाङ्नाम कविः प्राणाश्रितस्तु यः॥