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Sunshine

On Earth solar radiation is obvious as daylight when the Sun is above the horizon. This is during daytime, and also in summer near the poles at night, but not at all in winter near the poles. When the direct radiation is not blocked by clouds, it is experienced as sunshine, a combination of bright yellow light (sunlight in the strict sense) and heat. The heat on the body, on objects, etc., that is directly produced by the radiation should be distinguished from the increase in air temperature.

Many people find the light too bright to be comfortable, especially when reading from paper on which the sun directly shines, and therefore wear sunglasses. Cars, many helmets and caps are equipped with a visor, to block a direct view of the sun when it is at a low angle.

In cold countries many people like sunny days and often prefer not to be in the shade. In hot countries the converse is true and in the midday hours many people prefer to stay inside if they can, because going out is uncomfortably hot, and if they go out, prefer to be in the shade. This is provided by trees, parasols, etc.

Sunshine into buildings is often blocked by blinds, awnings, shutters or curtains.

Sitting or lying in the sun (sunbathing) is a popular lounging type of leisure, on the beach, at the open air swimming pool, in the park, in the garden, in a pavement café, etc., often in swimsuit or otherwise with limited clothing, and nude in nudist areas. One of the purposes for people with a light skin color is often to make it darker (get a sun tan) as this is considered beautiful and is associated with health (although the opposite image is increasing in view of the health risks) and having enjoyed holidays.

The World Meteorological Organization defines there to be sunshine when the direct irradiance from the Sun measured on the ground is at least 120 Wm-2.

See also Solar radiation, Sunburn, Sunscreen