178 relations: Absorption (electromagnetic radiation), Absorption spectroscopy, Aerosol, ANSMET, Antarctica, Anticyclone, Asteroid, Asteroid belt, Astronomical object, Atmosphere of Earth, Atom, Atomic mass, Avogadro's law, Bar (unit), Boiling, Boiling point, Buoyancy, Capillary, Carbon dioxide, Ceres (dwarf planet), Chemical formula, Cloud, Cloud condensation nuclei, Cloud physics, Cobalt(II) chloride, Comet, Concentration, Condensation, Convection, Cryofixation, CW Leonis, Cyanoacrylate, Cyclone, Density, Density of air, Deposition (phase transition), Dew point, Dewcell, Differential optical absorption spectroscopy, Dwarf planet, Earth's energy budget, Eddy covariance, Electric charge, Electromagnetic absorption by water, Electromagnetic spectrum, Electron microscope, Electrostatic discharge, Enceladus, Enthalpy of vaporization, Environmental impact of aviation, ..., Equation of state, Europa (moon), European Remote-Sensing Satellite, Evaporation, Evaporative cooler, Exhalation, Exhaled breath condensate, Extrasolar object, Far-infrared astronomy, Fog, Frost, Gas, Gas constant, Gas laws, Geyser, Gibbs free energy, GOES 12, Goff–Gratch equation, Goldbeater's skin, Gram, Greenhouse gas, HAT-P-11b, HD 209458 b, Heat capacity, Herschel Space Observatory, Humidity, Humidity indicator card, HVAC, Hydrocarbon, Hydrogen, Hydrogen bond, Hydrosphere, Hydroxy group, Hygrometer, Icarus (journal), Ice, Icy moon, Ideal gas, Ideal gas law, Infrared, Insulator (electricity), Joule, Journal of Geophysical Research, Kelvin, Kilogram, Kinetic energy, Kinetic theory of gases, Lapse rate, Latent heat, Lifting gas, Lighter than air, Lightning, Lipid bilayer, Liquid, Mars, Measurement uncertainty, Melting point, Meteorite, Methane, MetOp, Micrograph, Microwave, Microwave radiometer, Millennium, Mist, Moisture analysis, Molar mass, Molar volume, Mole (unit), Molecule, NASA, Natural satellite, Nature (journal), Nitrogen, Organelle, Oxygen, Partial pressure, Pascal (unit), Permittivity, Phase (matter), Phase rule, Planetary and Space Science, Planetary system, Polyurethane, Precipitable water, Precipitation, Properties of water, Radar, Radio wave, Reflection (physics), Refraction, Refrigeration, Relative humidity, Respiration (physiology), Rust, Saturation vapor density, Scale height, Scanning electron microscope, Snowball Earth, Solar System, Spectroscopy, Standard conditions for temperature and pressure, Star, Static electricity, Steam, Steam power during the Industrial Revolution, Subaerial eruption, Sublimation (phase transition), Sun, Sunspot, Superheating, Supersaturation, The Astrophysical Journal, Thermal airship, Thermal comfort, Thermodynamics, Thunderstorm, Tidal heating, Titan (moon), Tropical cyclone, Tropopause, Troposphere, Vapor, Vapor pressure, Vienna Standard Mean Ocean Water, Volcanic gas, Volcano, Water cycle. Expand index (128 more) » « Shrink index
In physics, absorption of electromagnetic radiation is the way in which the energy of a photon is taken up by matter, typically the electrons of an atom.
Absorption spectroscopy refers to spectroscopic techniques that measure the absorption of radiation, as a function of frequency or wavelength, due to its interaction with a sample.
An aerosol is a suspension of fine solid particles or liquid droplets, in air or another gas.
ANSMET (Antarctic Search for Meteorites) is a program funded by the Office of Polar Programs of the National Science Foundation that looks for meteorites in the Transantarctic Mountains.
Antarctica is Earth's southernmost continent.
An anticyclone (that is, opposite to a cyclone) is a weather phenomenon defined by the United States National Weather Service's glossary as "a large-scale circulation of winds around a central region of high atmospheric pressure, clockwise in the Northern Hemisphere, counterclockwise in the Southern Hemisphere".
Asteroids are minor planets, especially those of the inner Solar System.
The asteroid belt is the circumstellar disc in the Solar System located roughly between the orbits of the planets Mars and Jupiter.
An astronomical object or celestial object is a naturally occurring physical entity, association, or structure that exists in the observable universe.
The atmosphere of Earth is the layer of gases, commonly known as air, that surrounds the planet Earth and is retained by Earth's gravity.
An atom is the smallest constituent unit of ordinary matter that has the properties of a chemical element.
The atomic mass (ma) is the mass of an atom.
Avogadro's law (sometimes referred to as Avogadro's hypothesis or Avogadro's principle) is an experimental gas law relating the volume of a gas to the amount of substance of gas present.
The bar is a metric unit of pressure, but is not approved as part of the International System of Units (SI).
Boiling is the rapid vaporization of a liquid, which occurs when a liquid is heated to its boiling point, the temperature at which the vapour pressure of the liquid is equal to the pressure exerted on the liquid by the surrounding atmosphere.
The boiling point of a substance is the temperature at which the vapor pressure of the liquid equals the pressure surrounding the liquid and the liquid changes into a vapor.
In physics, buoyancy or upthrust, is an upward force exerted by a fluid that opposes the weight of an immersed object.
A capillary is a small blood vessel from 5 to 10 micrometres (µm) in diameter, and having a wall one endothelial cell thick.
Carbon dioxide (chemical formula) is a colorless gas with a density about 60% higher than that of dry air.
Ceres (minor-planet designation: 1 Ceres) is the largest object in the asteroid belt that lies between the orbits of Mars and Jupiter, slightly closer to Mars' orbit.
A chemical formula is a way of presenting information about the chemical proportions of atoms that constitute a particular chemical compound or molecule, using chemical element symbols, numbers, and sometimes also other symbols, such as parentheses, dashes, brackets, commas and plus (+) and minus (−) signs.
In meteorology, a cloud is an aerosol consisting of a visible mass of minute liquid droplets, frozen crystals, or other particles suspended in the atmosphere of a planetary body.
Cloud condensation nuclei or CCNs (also known as cloud seeds) are small particles typically 0.2 µm, or 1/100th the size of a cloud droplet on which water vapor condenses.
Cloud physics is the study of the physical processes that lead to the formation, growth and precipitation of atmospheric clouds.
Cobalt(II) chloride is an inorganic compound of cobalt and chlorine, with the formula CoCl2.
A comet is an icy small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process called outgassing.
In chemistry, concentration is the abundance of a constituent divided by the total volume of a mixture.
Condensation is the change of the physical state of matter from gas phase into liquid phase, and is the reverse of vapourisation.
Convection is the heat transfer due to bulk movement of molecules within fluids such as gases and liquids, including molten rock (rheid).
Cryofixation is a technique for fixation or stabilisation of biological materials as the first step in specimen preparation for electron microscopy and cryo-electron microscopy.
IRC +10216 or CW Leonis is a well-studied carbon star that is embedded in a thick dust envelope. It was first discovered in 1969 by a group of astronomers led by Eric Becklin, based upon infrared observations made with the Caltech Infrared Telescope at Mount Wilson Observatory. Its energy is emitted mostly at infrared wavelengths. At a wavelength of 5 μm, it was found to have the highest flux of any object outside the Solar System.
Cyanoacrylates are a family of strong fast-acting adhesives with industrial, medical, and household uses.
In meteorology, a cyclone is a large scale air mass that rotates around a strong center of low atmospheric pressure.
The density, or more precisely, the volumetric mass density, of a substance is its mass per unit volume.
The density of air ρ (Greek: rho) (air density) is the mass per unit volume of Earth's atmosphere.
Deposition is a thermodynamic process, a phase transition in which gas transforms into solid without passing through the liquid phase.
The dew point is the temperature to which air must be cooled to become saturated with water vapor.
Dewcells, Translation Bureau dewcels or dew cell are instruments used for determining the dew point.
In atmospheric chemistry, differential optical absorption spectroscopy (DOAS) is used to measure concentrations of trace gases.
A dwarf planet is a planetary-mass object that is neither a planet nor a natural satellite.
Earth's energy budget accounts for the balance between energy Earth receives from the Sun, energy Earth radiates back into outer space after having been distributed throughout the five components of Earth's climate system and having thus powered the so-called "Earth’s heat engine".
The eddy covariance (also known as eddy correlation and eddy flux) technique is a key atmospheric measurement technique to measure and calculate vertical turbulent fluxes within atmospheric boundary layers.
Electric charge is the physical property of matter that causes it to experience a force when placed in an electromagnetic field.
The absorption of electromagnetic radiation by water depends on the state of the water.
The electromagnetic spectrum is the range of frequencies (the spectrum) of electromagnetic radiation and their respective wavelengths and photon energies.
An electron microscope is a microscope that uses a beam of accelerated electrons as a source of illumination.
Electrostatic discharge (ESD) is the sudden flow of electricity between two electrically charged objects caused by contact, an electrical short, or dielectric breakdown.
Enceladus is the sixth-largest moon of Saturn.
The enthalpy of vaporization, (symbol ∆Hvap) also known as the (latent) heat of vaporization or heat of evaporation, is the amount of energy (enthalpy) that must be added to a liquid substance, to transform a quantity of that substance into a gas.
The environmental impact of aviation occurs because aircraft engines emit heat, noise, particulates, and gases which contribute to climate change and global dimming.
In physics and thermodynamics, an equation of state is a thermodynamic equation relating state variables which describe the state of matter under a given set of physical conditions, such as pressure, volume, temperature (PVT), or internal energy.
Europa or as Ευρώπη (Jupiter II) is the smallest of the four Galilean moons orbiting Jupiter, and the sixth-closest to the planet.
European remote sensing satellite (ERS) was the European Space Agency's first Earth-observing satellite programme using a polar orbit.
Evaporation is a type of vaporization that occurs on the surface of a liquid as it changes into the gaseous phase before reaching its boiling point.
An evaporative cooler (also swamp cooler, desert cooler and wet air cooler) is a device that cools air through the evaporation of water.
Exhalation (or expiration) is the flow of the breath out of an organism.
Exhaled breath condensate (EBC) is the exhalate from breath, that has been condensed, typically via cooling using a collection device (commonly to 4 °C or subzero temperatures using a refrigerating device).
An extrasolar object is an astronomical object that exists outside the Solar System.
Far-infrared astronomy is the branch of astronomy and astrophysics that deals with objects visible in far-infrared radiation (extending from 30 µm towards submillimeter wavelengths around 450 µm).
Fog is a visible aerosol consisting of minute water droplets or ice crystals suspended in the air at or near the Earth's surface.
Frost is the coating or deposit of ice that may form in humid air in cold conditions, usually overnight.
Gas is one of the four fundamental states of matter (the others being solid, liquid, and plasma).
The gas constant is also known as the molar, universal, or ideal gas constant, denoted by the symbol or and is equivalent to the Boltzmann constant, but expressed in units of energy per temperature increment per mole, i.e. the pressure-volume product, rather than energy per temperature increment per particle.
The gas laws were developed at the end of the 18th century, when scientists began to realize that relationships between pressure, volume and temperature of a sample of gas could be obtained which would hold to approximation for all gases.
A geyser is a spring characterized by intermittent discharge of water ejected turbulently and accompanied by steam.
In thermodynamics, the Gibbs free energy (IUPAC recommended name: Gibbs energy or Gibbs function; also known as free enthalpy to distinguish it from Helmholtz free energy) is a thermodynamic potential that can be used to calculate the maximum of reversible work that may be performed by a thermodynamic system at a constant temperature and pressure (isothermal, isobaric).
GOES 12, known as GOES-M before becoming operational, is an American weather satellite, which is part of the US National Oceanic and Atmospheric Administration's Geostationary Operational Environmental Satellite system.
The Goff–Gratch equation is one (arguably the first reliable in history) amongst many experimental correlation proposed to estimate the saturation water vapor pressure at a given temperature.
Goldbeater's skin is the processed outer membrane of the intestine of an animal, typically an ox, valued for its strength against tearing.
The gram (alternative spelling: gramme; SI unit symbol: g) (Latin gramma, from Greek γράμμα, grámma) is a metric system unit of mass.
A greenhouse gas is a gas in an atmosphere that absorbs and emits radiant energy within the thermal infrared range.
HAT-P-11b (or Kepler-3b) is an extrasolar planet.
HD 209458 b, also given the nickname Osiris,http://exoplanets.co/exoplanets-tutorial/extrasolar-planet-hd-209458-b.html is an exoplanet that orbits the solar analog HD 209458 in the constellation Pegasus, some 159 light-years from the Solar System.
Heat capacity or thermal capacity is a measurable physical quantity equal to the ratio of the heat added to (or removed from) an object to the resulting temperature change.
The Herschel Space Observatory was a space observatory built and operated by the European Space Agency (ESA).
Humidity is the amount of water vapor present in the air.
A humidity indicator card (HIC) is a card on which a moisture-sensitive chemical is impregnated such that it will change color when the indicated relative humidity is exceeded.
Heating, ventilation and air conditioning (HVAC) is the technology of indoor and vehicular environmental comfort.
In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon.
Hydrogen is a chemical element with symbol H and atomic number 1.
A hydrogen bond is a partially electrostatic attraction between a hydrogen (H) which is bound to a more electronegative atom such as nitrogen (N), oxygen (O), or fluorine (F), and another adjacent atom bearing a lone pair of electrons.
The hydrosphere (from Greek ὕδωρ hydōr, "water" and σφαῖρα sphaira, "sphere") is the combined mass of water found on, under, and above the surface of a planet, minor planet or natural satellite.
A hydroxy or hydroxyl group is the entity with the formula OH.
A hygrometer is an instrument used for measuring the amount of humidity and water vapor in the atmosphere, in soil, or in confined spaces.
Icarus is a scientific journal dedicated to the field of planetary science.
Ice is water frozen into a solid state.
Icy moons are a class of natural satellites with surfaces composed mostly of ice.
An ideal gas is a theoretical gas composed of many randomly moving point particles whose only interactions are perfectly elastic collisions.
The ideal gas law, also called the general gas equation, is the equation of state of a hypothetical ideal gas.
Infrared radiation (IR) is electromagnetic radiation (EMR) with longer wavelengths than those of visible light, and is therefore generally invisible to the human eye (although IR at wavelengths up to 1050 nm from specially pulsed lasers can be seen by humans under certain conditions). It is sometimes called infrared light.
An electrical insulator is a material whose internal electric charges do not flow freely; very little electric current will flow through it under the influence of an electric field.
The joule (symbol: J) is a derived unit of energy in the International System of Units.
The Journal of Geophysical Research is a peer-reviewed scientific journal.
The Kelvin scale is an absolute thermodynamic temperature scale using as its null point absolute zero, the temperature at which all thermal motion ceases in the classical description of thermodynamics.
The kilogram or kilogramme (symbol: kg) is the base unit of mass in the International System of Units (SI), and is defined as being equal to the mass of the International Prototype of the Kilogram (IPK, also known as "Le Grand K" or "Big K"), a cylinder of platinum-iridium alloy stored by the International Bureau of Weights and Measures at Saint-Cloud, France.
In physics, the kinetic energy of an object is the energy that it possesses due to its motion.
The kinetic theory describes a gas as a large number of submicroscopic particles (atoms or molecules), all of which are in constant rapid motion that has randomness arising from their many collisions with each other and with the walls of the container.
Lapse rate is the rate at which Earth's atmospheric temperature decreases with an increase in altitude, or increases with the decrease in altitude.
Latent heat is thermal energy released or absorbed, by a body or a thermodynamic system, during a constant-temperature process — usually a first-order phase transition.
Because of Archimedes' principle, a lifting gas is required for aerostats to create buoyancy.
Lighter than air refers to materials (usually gases) that are buoyant in air because they have average densities lower than that of air.
Lightning is a sudden electrostatic discharge that occurs typically during a thunderstorm.
The lipid bilayer (or phospholipid bilayer) is a thin polar membrane made of two layers of lipid molecules.
A liquid is a nearly incompressible fluid that conforms to the shape of its container but retains a (nearly) constant volume independent of pressure.
Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System after Mercury.
In metrology, measurement uncertainty is a non-negative parameter characterizing the dispersion of the values attributed to a measured quantity.
The melting point (or, rarely, liquefaction point) of a substance is the temperature at which it changes state from solid to liquid at atmospheric pressure.
A meteorite is a solid piece of debris from an object, such as a comet, asteroid, or meteoroid, that originates in outer space and survives its passage through the atmosphere to reach the surface of a planet or moon.
Methane is a chemical compound with the chemical formula (one atom of carbon and four atoms of hydrogen).
MetOp is a series of three polar orbiting meteorological satellites developed by the European Space Agency (ESA) and operated by the European Organization for the Exploitation of Meteorological Satellites (EUMETSAT).
A micrograph or photomicrograph is a photograph or digital image taken through a microscope or similar device to show a magnified image of an item.
Microwaves are a form of electromagnetic radiation with wavelengths ranging from one meter to one millimeter; with frequencies between and.
A microwave radiometer (MWR) is a radiometer that measures energy emitted at millimetre-to-centimetre wavelengths (frequencies of 1–1000 GHz) known as microwaves.
A millennium (plural millennia or, rarely, millenniums) is a period equal to 1000 years, also called kiloyears.
Mist is a phenomenon caused by small droplets of water suspended in air.
Moisture analysis covers a variety of methods for measuring moisture content in both high level and trace amounts in solids, liquids, or gases.
In chemistry, the molar mass M is a physical property defined as the mass of a given substance (chemical element or chemical compound) divided by the amount of substance.
The molar volume, symbol Vm, is the volume occupied by one mole of a substance (chemical element or chemical compound) at a given temperature and pressure.
The mole, symbol mol, is the SI unit of amount of substance.
A molecule is an electrically neutral group of two or more atoms held together by chemical bonds.
The National Aeronautics and Space Administration (NASA) is an independent agency of the executive branch of the United States federal government responsible for the civilian space program, as well as aeronautics and aerospace research.
A natural satellite or moon is, in the most common usage, an astronomical body that orbits a planet or minor planet (or sometimes another small Solar System body).
Nature is a British multidisciplinary scientific journal, first published on 4 November 1869.
Nitrogen is a chemical element with symbol N and atomic number 7.
In cell biology, an organelle is a specialized subunit within a cell that has a specific function, in which their function is vital for the cell to live.
Oxygen is a chemical element with symbol O and atomic number 8.
In a mixture of gases, each gas has a partial pressure which is the hypothetical pressure of that gas if it alone occupied the entire volume of the original mixture at the same temperature.
The pascal (symbol: Pa) is the SI derived unit of pressure used to quantify internal pressure, stress, Young's modulus and ultimate tensile strength.
In electromagnetism, absolute permittivity, often simply called permittivity, usually denoted by the Greek letter ε (epsilon), is the measure of resistance that is encountered when forming an electric field in a particular medium.
In the physical sciences, a phase is a region of space (a thermodynamic system), throughout which all physical properties of a material are essentially uniform.
Gibbs' phase rule Chapter 6 was proposed by Josiah Willard Gibbs in his landmark paper titled On the Equilibrium of Heterogeneous Substances, published from 1875 to 1878.
Planetary and Space Science, published 15 times per year, is a peer-reviewed scientific journal established in 1959.
A planetary system is a set of gravitationally bound non-stellar objects in or out of orbit around a star or star system.
Polyurethane (PUR and PU) is a polymer composed of organic units joined by carbamate (urethane) links.
Precipitable water is the depth of water in a column of the atmosphere, if all the water in that column were precipitated as rain.
In meteorology, precipitation is any product of the condensation of atmospheric water vapor that falls under gravity.
Water is a polar inorganic compound that is at room temperature a tasteless and odorless liquid, which is nearly colorless apart from an inherent hint of blue. It is by far the most studied chemical compound and is described as the "universal solvent" and the "solvent of life". It is the most abundant substance on Earth and the only common substance to exist as a solid, liquid, and gas on Earth's surface. It is also the third most abundant molecule in the universe. Water molecules form hydrogen bonds with each other and are strongly polar. This polarity allows it to separate ions in salts and strongly bond to other polar substances such as alcohols and acids, thus dissolving them. Its hydrogen bonding causes its many unique properties, such as having a solid form less dense than its liquid form, a relatively high boiling point of 100 °C for its molar mass, and a high heat capacity. Water is amphoteric, meaning that it is both an acid and a base—it produces + and - ions by self-ionization.
Radar is an object-detection system that uses radio waves to determine the range, angle, or velocity of objects.
Radio waves are a type of electromagnetic radiation with wavelengths in the electromagnetic spectrum longer than infrared light.
Reflection is the change in direction of a wavefront at an interface between two different media so that the wavefront returns into the medium from which it originated.
Refraction is the change in direction of wave propagation due to a change in its transmission medium.
Refrigeration is a process of removing heat from a low-temperature reservoir and transferring it to a high-temperature reservoir.
Relative humidity (RH) is the ratio of the partial pressure of water vapor to the equilibrium vapor pressure of water at a given temperature.
In physiology, respiration is defined as the movement of oxygen from the outside environment to the cells within tissues, and the transport of carbon dioxide in the opposite direction.
Rust is an iron oxide, a usually red oxide formed by the redox reaction of iron and oxygen in the presence of water or air moisture.
Saturation vapor density (SVD) is a concept closely tied with saturation vapor pressure (SVP).
In various scientific contexts, a scale height is a distance over which a quantity decreases by a factor of e (approximately 2.72, the base of natural logarithms).
A scanning electron microscope (SEM) is a type of electron microscope that produces images of a sample by scanning the surface with a focused beam of electrons.
The Snowball Earth hypothesis proposes that Earth surface's became entirely or nearly entirely frozen at least once, sometime earlier than 650 Mya (million years ago).
The Solar SystemCapitalization of the name varies.
Spectroscopy is the study of the interaction between matter and electromagnetic radiation.
Standard conditions for temperature and pressure are standard sets of conditions for experimental measurements to be established to allow comparisons to be made between different sets of data.
A star is type of astronomical object consisting of a luminous spheroid of plasma held together by its own gravity.
Static electricity is an imbalance of electric charges within or on the surface of a material.
Steam is water in the gas phase, which is formed when water boils.
Improvements to the steam engine were some of the most important technologies of the Industrial Revolution, although steam did not replace water power in importance in Britain until after the Industrial Revolution.
A subaerial eruption is a volcanic eruption that has occurred on the land surface, 'under the air'.
Sublimation is the transition of a substance directly from the solid to the gas phase, without passing through the intermediate liquid phase.
The Sun is the star at the center of the Solar System.
Sunspots are temporary phenomena on the Sun's photosphere that appear as spots darker than the surrounding areas.
In physics, superheating (sometimes referred to as boiling retardation, or boiling delay) is the phenomenon in which a liquid is heated to a temperature higher than its boiling point, without boiling.
Supersaturation is a state of a solution that contains more of the dissolved material than could be dissolved by the solvent under normal circumstances.
The Astrophysical Journal, often abbreviated ApJ (pronounced "ap jay") in references and speech, is a peer-reviewed scientific journal of astrophysics and astronomy, established in 1895 by American astronomers George Ellery Hale and James Edward Keeler.
A thermal airship is an airship that generates buoyancy by heating air in a large chamber or envelope.
Thermal comfort is the condition of mind that expresses satisfaction with the thermal environment and is assessed by subjective evaluation (ANSI/ASHRAE Standard 55).
Thermodynamics is the branch of physics concerned with heat and temperature and their relation to energy and work.
A thunderstorm, also known as an electrical storm, lightning storm, or thundershower, is a storm characterized by the presence of lightning and its acoustic effect on the Earth's atmosphere, known as thunder.
Tidal heating (also known as tidal working or tidal flexing) occurs through the tidal friction processes: orbital energy is dissipated as heat in either the surface ocean or interior of a planet or satellite.
Titan is the largest moon of Saturn.
A tropical cyclone is a rapidly rotating storm system characterized by a low-pressure center, a closed low-level atmospheric circulation, strong winds, and a spiral arrangement of thunderstorms that produce heavy rain.
The tropopause is the boundary in the Earth's atmosphere between the troposphere and the stratosphere.
The troposphere is the lowest layer of Earth's atmosphere, and is also where nearly all weather conditions take place.
In physics a vapor (American) or vapour (British and Canadian) is a substance in the gas phase at a temperature lower than its critical temperature,R.
Vapor pressure or equilibrium vapor pressure is defined as the pressure exerted by a vapor in thermodynamic equilibrium with its condensed phases (solid or liquid) at a given temperature in a closed system.
Vienna Standard Mean Ocean Water (VSMOW) is a water standard defining the isotopic composition of fresh water.
Volcanic gases are gases given off by active (or, at times, by dormant) volcanoes.
A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface.
The water cycle, also known as the hydrological cycle or the hydrologic cycle, describes the continuous movement of water on, above and below the surface of the Earth.