If you have a column of air limited by two isobaric surfaces at a pressure difference of 100 hPa, the distance between the pressure surfaces will change if mean temperature and mean pressure of the column of air change.
In which of the following alternatives will the change of temperature and pressure interact to shorten the distance as much as possible?
The temperature increases and pressure increases.
The temperature decreases and pressure increases.
The temperature increases and pressure decreases.
The temperature decreases and pressure decreases.