Monitor temperatures help a newb out

This has baffled me ever since I've had this monitor

it a Diamond View 19" model 1995

in the screen options it has 5 optional temperatures and then a secaond screen that allow u to adjust the overal RGB channels

the temps ranage from 5500 Kelvin up to 11500 Kelvin

although the default setting make each temp give the screen a slightly differnt Hue of colour you can alter the RGB channel and it all looks the same.

The only thing I can think it could possible do would be to offer a greater range of colours the monitor can display or perhaps a greater visual stabilioty.

Des anyone know why the diff temps have an effect on ? and what effect will it have on lifespan to run at 11500 kelvin vs 5500 Kelvin for example.