Molecular massThe molecular mass (m) is the mass of a given molecule, for which the unit dalton (Da) is used. Different molecules of the same compound may have different molecular masses because they contain different isotopes of an element. The related quantity relative molecular mass, as defined by IUPAC, is the ratio of the mass of a molecule to the atomic mass constant (which is equal to one dalton) and is unitless. The molecular mass and relative molecular mass are distinct from but related to the molar mass.
Mole fractionIn chemistry, the mole fraction or molar fraction (xi or χi) is defined as unit of the amount of a constituent (expressed in moles), ni, divided by the total amount of all constituents in a mixture (also expressed in moles), ntot. This expression is given below: The sum of all the mole fractions is equal to 1: The same concept expressed with a denominator of 100 is the mole percent, molar percentage or molar proportion (mol%). The mole fraction is also called the amount fraction.
Adiabatic processIn thermodynamics, an adiabatic process (Greek: adiábatos, "impassable") is a type of thermodynamic process that occurs without transferring heat or mass between the thermodynamic system and its environment. Unlike an isothermal process, an adiabatic process transfers energy to the surroundings only as work. As a key concept in thermodynamics, the adiabatic process supports the theory that explains the first law of thermodynamics. Some chemical and physical processes occur too rapidly for energy to enter or leave the system as heat, allowing a convenient "adiabatic approximation".
Radiation pressureRadiation pressure (also known as light pressure) is the mechanical pressure exerted upon any surface due to the exchange of momentum between the object and the electromagnetic field. This includes the momentum of light or electromagnetic radiation of any wavelength that is absorbed, reflected, or otherwise emitted (e.g. black-body radiation) by matter on any scale (from macroscopic objects to dust particles to gas molecules). The associated force is called the radiation pressure force, or sometimes just the force of light.
BiosphereThe biosphere (from Greek βίος bíos "life" and σφαῖρα sphaira "sphere"), also known as the ecosphere (from Greek οἶκος oîkos "environment" and σφαῖρα), is the worldwide sum of all ecosystems. It can also be termed the zone of life on Earth. The biosphere (which is technically a spherical shell) is virtually a closed system with regard to matter, with minimal inputs and outputs. Regarding energy, it is an open system, with photosynthesis capturing solar energy at a rate of around 100 terawatts.
DustDust is made of fine particles of solid matter. On Earth, it generally consists of atmospheric particulates (particles in the atmosphere) that come from various sources such as soil lifted by wind (an aeolian process), volcanic eruptions, and pollution. Dust in homes is composed of about 20–50% dead skin cells. The rest, and in offices, and other human environments is composed of small amounts of plant pollen, human hairs, animal fur, textile fibers, paper fibers, minerals from outdoor soil, burnt meteorite particles, and many other materials which may be found in the local environment.
Climate modelNumerical climate models use quantitative methods to simulate the interactions of the important drivers of climate, including atmosphere, oceans, land surface and ice. They are used for a variety of purposes from study of the dynamics of the climate system to projections of future climate. Climate models may also be qualitative (i.e. not numerical) models and also narratives, largely descriptive, of possible futures.
Radiative coolingIn the study of heat transfer, radiative cooling is the process by which a body loses heat by thermal radiation. As Planck's law describes, every physical body spontaneously and continuously emits electromagnetic radiation. Radiative cooling has been applied in various contexts throughout human history, including ice making in India and Iran, heat shields for spacecraft, and in architecture. In 2014, a scientific breakthrough in the use of photonic metamaterials made daytime radiative cooling possible.
DawnDawn is the time that marks the beginning of twilight before sunrise. It is recognized by the appearance of indirect sunlight being scattered in Earth's atmosphere, when the centre of the Sun's disc has reached 18° below the observer's horizon. This morning twilight period will last until sunrise (when the Sun's upper limb breaks the horizon), when direct sunlight outshines the diffused light. "Dawn" derives from the Old English verb dagian, "to become day".
National Oceanic and Atmospheric AdministrationThe National Oceanic and Atmospheric Administration (abbreviated as NOAA ˈnoʊ.ə ) is a Washington, D.C.–based scientific and regulatory agency within the United States Department of Commerce, a United States federal government department. The agency is charged with forecasting weather, monitoring oceanic and atmospheric conditions, charting the seas, conducting deep sea exploration, and managing fishing and protection of marine mammals and endangered species in the U.S. exclusive economic zone.
