fire & explosion in unprotected cargo tanks of oil tanker can have wide variety of causes identify one that is associated with bad weather condition

 fire & explosion in unprotected cargo tanks of oil tanker can have a wide variety of causes identify one that is associated with bad weather condition

1) vapours from lifting or leaking cargo tank relief valves ignited by lightning discharge
2) empty tank gas ignited during cleaning or collision resulting in an explosion and rupture on the main deck

Ans_____1) vapours from lifting or leaking cargo tank relief valves ignited by lightning discharge