Rare heatwave modelling A-level Physics challenge

A model represents $2.0\times 10^{15}\mathrm{kg}$ of air over a region. The mean temperature of this air rises by $4.0\mathrm{K}$. Use a mean specific heat capacity of $1.0\times 10^3\mathrm{J}{\mathrm{kg}}^{-1}{\mathrm{K}}^{-1}$. Estimate the increase in internal energy of the modelled air.

A simulated heatwave develops when the rate of energy absorbed by the land-atmosphere region remains greater than the rate at which energy leaves. Explain how this imbalance raises air temperature and give one physical process the model must represent.

The fast AI forecast and the slower physics-based climate model do not always predict exactly the same temperature. Before the combined method is trusted, researchers must check both its physical energy balance and its predictions. Describe three checks they should make.