solar radiation

The sun emits electromagnetic radiation in different wavelengths. It reaches the earth as light, UV radiation, and infrared radiation (heat). It has effects on the eyes, skin and thermal balance.

Part of the radiation emitted by the sun reaches the earth directly (1), another part is first absorbed and/or scattered by the atmosphere and clouds, thus reaching the earth indirectly (4). The earth in turn reflects (2) part of the radiation and absorbs (3) the rest.

The different types of radiation have different effects on our well-being. UV radiation is needed for the production of vitamin D, but in large amounts causes sunburn, accelerated skin ageing and different types of skin cancer. Heat – too much or too little of it – can lead to various illnesses; high temperatures can lead to conditions varying from heat rash at one end of the spectrum to heat stroke at the other end, low temperatures can be associated with increased mortality due to cerebrovascular, cardiovascular and respiratory disease. The effects of daylight are discussed separately.

Principles

Guidelines

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