Solar Irradiance (Leaving Cert Physics): Flashcards

Power per unit area from Sun on 1 m² surface (W m⁻²)

Watts per square metre (W m⁻²)

$I = \frac{P}{A}$ where $I$ = irradiance, $P$ = power, $A$ = area

UVC radiation (highest frequency, most energetic)

Sunburn and DNA damage (can lead to skin cancer)

Vitamin D synthesis in skin

Lowest energy UV, penetrates deeper, causes skin ageing

Time of day, season, location, atmospheric conditions

Sunscreen, clothing, shade, avoid peak hours, sunglasses

Damages cells, reduces photosynthesis, lowers growth/yield