Question

Why does solubility of gases increase with decrease in temperature?

Answer 1

It has to do with the increase of kinetic energy in the system. Gas already has a large amount of kinetic energy (gas phase) so when you start to add more energy into the system (heat) you increase the kinetic energy of the fluid elevating it’s vapor pressure.
As the solvent vapor pressure increases with the additional kinetic energy the entire system becomes volatile, because you have additional kinetic energy. This prevents more gas from dissolving into the system.
or simply
Increased temperature causes an increase in kinetic energy. The higher kinetic energy causes more motion in the gasmolecules which break intermolecular bonds and escape from solution