RSS (satellite) Record
The start date of the satellite record is 1979. It appears that Antarctic temperature peaked around before 1882 and has declined slightly since then.
Satellite temperature is actually a measure of the level of radiative energy of the atmosphere. The anomalies show the changes in the level of energy at the measured wavelengths. As a consequence, the integral of the changes may indicate the direction of change.
The integral of temperature may not have an obvious physical meaning apart from the vibration energy of the molecules in the atmosphere. However, in some years higher temperature indicates that energy is being added to the oceans while in other year energy is being lost.
The integral of of temperature is a proxy for the running total of net energy lost and gained that indicates the direction of change more clearly than does the temperature.