The present invention relates to an improved countermeasure for circadian and sleep disruption as caused by a traditional alarm clock. It incorporates a lighting system at the alarm clock that, prior to the preset waking time, will emit a light that gradually increases in intensity as it changes the ultraviolet spectrum of light it emits, so as to simulate the rising sun. This will ease the waking process for many people, especially those prone to simple disruptions of their circadian regulation. It may also be set to operate in a reverse mode so as to simulate the setting sun thus helping stimulate melatonin production and easing one into sleep.