Ultraviolet radiation is the energy range just beyond the violet end of the visible spectrum. Although ultraviolet radiation constitutes only about 5 per cent of the total energy emitted from the sun, it is the primary energy source for the stratosphere and mesosphere, and it’s vital in energy balance as well chemical composition.
ULTRAVIOLET RADIATION (UV) DIAGRAM
UN Global Compact is a voluntary initiative to encourage businesses to adopt and report on sustainable and socially responsible policies. It seeks to align business operations and strategies with ten universally accepted principles in the areas of human rights, labour, environment and anti-corruption
UN GLOBAL COMPACT
Underground homes are a term used to describe a house built into the ground or slope of a hill, or which has most or all exterior surfaces covered with earth. Because its earth insulation serves as a thermal mass, it retains warmth in winter and remains cool in summer.
UNEP united nations environment Program
UNESCO The United Nations educational, scientific and cultural organization
Uniformitarianism is aa term used to describe the principle that geological events explained by processes observable today (the present is the key to the past). It assumes these processes have not changed during geological time.