Background information on thermal energy transfer and conservation of energy

Generally, when thermal energy is transferred to a material, the motion of its particles speeds up and its temperature increases. There are three methods of thermal energy transfer: conduction, convection, and radiation. ... Convection transfers thermal energy through the movement of fluids or gases in circulation cells.Convection. When a fluid, such as air or a liquid, is heated and then travels away from the source, it carries the thermal energy along. This type of heat transfer is called convection. The fluid above a hot surface expands, becomes less dense, and rises.

pe = weightxheight = 2000x1000=2,000,000joules

see earlier answer