Oxford Index Browse

An air-source *heat pump (ASHP) that uses heat rather than electricity to drive it. In a water and lithium

Rain containing high levels of sulphuric and nitric acid, caused by sulphur dioxide and nitric oxides, which are emitted in

The actions taken to reduce the adverse effects of *climate change. Examples of adaptation are raising coastal defences

Relating to a process in which there is no heat transfer between the system and its surroundings. It is an

The process of maintaining a space at a desired temperature and humidity. Usually cooling is implied and typically this is

When the optical path length L through the atmosphere for solar radiation incident at an angle θ _N is such

Airtightness is measured by the number of air changes per hour (ach) that occur when there is a differential pressure

The fraction of the Sun’s radiation reaching something—for example a cloud, or a whole planet—that is reflected. The Earth’s albedo

Fuels derived from plant oils produced by algae, predominantly microalgae. Microalgae can produce more than 50 per cent of their

An electric current that periodically flows in a conductor in one direction and then in the opposite.

Energy derived from non-fossil fuel sources. The alternative energy sources include *renewable energy sources and *nuclear energy.

The decomposition of organic matter by bacteria in the absence of air. Bacteria break down the organic material and produce

Human-induced changes to the climate, notably *global warming, caused by the emission of *greenhouse gases, in

The air temperature at a reference humidity (that which has a dew point of 14^°C), which feels as

A layer of porous rock, gravel, or sand—or of a similar composition—containing water (called groundwater). Aquifers close to the surface

Tiny liquid drops or solid particles that are sufficiently small (generally <1 micron) that they remain suspended in the air—conventionally

Transport by aircraft, predominantly by aeroplanes. In 2010, all forms of transport accounted for 27 per cent of global

The minimum demand from customers during twenty-four hours or some other defined period.

The electricity generation required to meet the *baseload. Baseload power plants operate whenever available, because they have lower

The value of the external temperature below which a building needs to be heated. For buildings in the UK that