What is a clear blue sky?

A clear blue sky refers to an expanse of sky that appears bright blue with minimal or no clouds. This phenomenon occurs when the atmosphere scatters sunlight, with shorter blue wavelengths being scattered more than other colors. Clear blue skies are often associated with good weather and can evoke feelings of tranquility and openness. Such skies are commonly observed during sunny days, especially in the absence of pollution or weather disturbances.