Atmospheric science is the study of the Earth's atmosphere, its processes, the effects other systems have on the atmosphere, and the effects of the atmosphere on these other systems. Meteorology includes atmospheric chemistry and atmospheric physics with a major focus on weather forecasting. Climatology is the study of atmospheric changes (both long and short-term) that define average climates and their change over time, due to both natural and anthropogenic climate variability. Aeronomy is the study of the upper layers of the atmosphere, where dissociation and ionization are important. Atmospheric science has been extended to the field of planetary science and the study of the atmospheres of the planets and natural satellites of the solar system.
The term aerology (from Greek ἀήρ, aēr, "air"; and -λογία, -logia) is sometimes used as an alternative term for the study of Earth's atmosphere; in other definitions, aerology is restricted to the free atmosphere, the region above the planetary boundary layer.
Atmospheric chemistry is a branch of atmospheric science in which the chemistry of the Earth's atmosphere and that of other planets is studied. It is a multidisciplinary field of research and draws on environmental chemistry, physics, meteorology, computer modeling, oceanography, geology and volcanology and other disciplines. Research is increasingly connected with other areas of study such as climatology.
The composition and chemistry of the atmosphere is of importance for several reasons, but primarily because of the interactions between the atmosphere and living organisms. The composition of the Earth's atmosphere has been changed by human activity and some of these changes are harmful to human health, crops and ecosystems. Examples of problems which have been addressed by atmospheric chemistry include acid rain, photochemical smog and global warming. Atmospheric chemistry seeks to understand the causes of these problems, and by obtaining a theoretical understanding of them, allow possible solutions to be tested and the effects of changes in government policy evaluated.
Atmospheric dynamics involves the study of observations and theory dealing with all motion systems of meteorological importance. Common topics studied include diverse phenomena such as thunderstorms, tornadoes, gravity waves, tropical cyclones, extratropical cyclones, jet streams, and global-scale circulations. The goal of dynamical studies is to explain the observed circulations on the basis of fundamental principles from physics. The objectives of such studies incorporate improving weather forecasting, developing methods for predicting seasonal and interannual climate fluctuations, and understanding the implications of human-induced perturbations (e.g., increased carbon dioxide concentrations or depletion of the ozone layer) on the global climate.
Atmospheric physics is the application of physics to the study of the atmosphere. Atmospheric physicists attempt to model Earth's atmosphere and the atmospheres of the other planets using fluid flow equations, chemical models, radiation balancing, and energy transfer processes in the atmosphere and underlying oceans. In order to model weather systems, atmospheric physicists employ elements of scattering theory, wave propagation models, cloud physics, statistical mechanics and spatial statistics, each of which incorporate high levels of mathematics and physics. Atmospheric physics has close links to meteorology and climatology and also covers the design and construction of instruments for studying the atmosphere and the interpretation of the data they provide, including remote sensing instruments.
In the United Kingdom, atmospheric studies are underpinned by the Meteorological Office. Divisions of the U.S. National Oceanic and Atmospheric Administration (NOAA) oversee research projects and weather modeling involving atmospheric physics. The U.S. National Astronomy and Ionosphere Center also carries out studies of the high atmosphere.
In contrast to meteorology, which studies short term weather systems lasting up to a few weeks, climatology studies the frequency and trends of those systems. It studies the periodicity of weather events over years to millennia, as well as changes in long-term average weather patterns, in relation to atmospheric conditions. Climatologists, those who practice climatology, study both the nature of climates – local, regional or global – and the natural or human-induced factors that cause climates to change. Climatology considers the past and can help predict future climate change.
Phenomena of climatological interest include the atmospheric boundary layer, circulation patterns, heat transfer (radiative, convective and latent), interactions between the atmosphere and the oceans and land surface (particularly vegetation, land use and topography), and the chemical and physical composition of the atmosphere. Related disciplines include astrophysics, atmospheric physics, chemistry, ecology, physical geography, geology, geophysics, glaciology, hydrology, oceanography, and volcanology.
All of the Solar System's planets have atmospheres. This is because their gravity is strong enough to keep gaseous particles close to the surface. Larger gas giants are massive enough to keep large amounts of the light gases hydrogen and helium close by, while the smaller planets lose these gases into space. The composition of the Earth's atmosphere is different from the other planets because the various life processes that have transpired on the planet have introduced free molecular oxygen. Much of Mercury's atmosphere has been blasted away by the solar wind. The only moon that has retained a dense atmosphere is Titan. There is a thin atmosphere on Triton, and a trace of an atmosphere on the Moon.
Planetary atmospheres are affected by the varying degrees of energy received from either the Sun or their interiors, leading to the formation of dynamic weather systems such as hurricanes, (on Earth), planet-wide dust storms (on Mars), an Earth-sized anticyclone on Jupiter (called the Great Red Spot), and holes in the atmosphere (on Neptune). At least one extrasolar planet, HD 189733 b, has been claimed to possess such a weather system, similar to the Great Red Spot but twice as large.
Hot Jupiters have been shown to be losing their atmospheres into space due to stellar radiation, much like the tails of comets. These planets may have vast differences in temperature between their day and night sides which produce supersonic winds, although the day and night sides of HD 189733b appear to have very similar temperatures, indicating that planet's atmosphere effectively redistributes the star's energy around the planet.
The 1566 celestial phenomenon over Basel was a series of mass sightings of celestial phenomena above Basel, Switzerland. The Basel pamphlet of 1566 describes unusual sunrises and sunsets. Celestial phenomena were said to have "fought" together in the form of numerous red and black balls in the sky before the rising sun. The report is discussed among historians and meteorologists. The phenomenon has been interpreted by some ufologists to be a sky battle between unidentified flying objects. The leaflet written by historian Samuel Coccius reported it as a religious event. The Basel pamphlet of 1566 is not the only one of its kind. In the 15th and 16th centuries, many leaflets wrote of "miracles" and "sky spectacles".Climate of Saudi Arabia
The climate of Saudi Arabia is marked by high temperatures during the day and low temperatures at night. The country follows the pattern of the desert climate, with the exception of the southwest, which features a semi-arid climate.Diurnal cycle
A diurnal cycle is any pattern that recurs every 24 hours as a result of one full rotation of the Earth around its own axis.
In climatology, the diurnal cycle is one of the most basic forms of climate patterns. The most familiar such pattern is the diurnal temperature variation. Such a cycle may be approximately sinusoidal, or include components of a truncated sinusoid (due to the Sun's rising and setting) and thermal relaxation (Newton cooling) at night.
Diurnal cycles of environmental conditions (light or temperature) can result in similar cycles in dependent biological processes, such as photosynthesis in plants, or clinical depression in humans. Plant responses to environmental cycles may even induce indirect cycles in rhizosphere microbial activities, including nitrogen fixation.A semi-diurnal cycle refers to a pattern that occurs about every twelve hours or about twice a day. Often these can be related to lunar tides, in which case the interval is closer to 12 hours and 25 minutes.Dry-bulb temperature
The dry-bulb temperature (DBT) is the temperature of air measured by a thermometer freely exposed to the air, but shielded from radiation and moisture. DBT is the temperature that is usually thought of as air temperature, and it is the true thermodynamic temperature. It indicates the amount of heat in the air and is directly proportional to the mean kinetic energy of the air molecules. Temperature is usually measured in degrees Celsius (°C), kelvins (K), or degrees Fahrenheit (°F).
Unlike wet-bulb temperature, dry bulb temperature does not indicate the amount of moisture in the air. In construction, it is an important consideration when designing a building for a certain climate. Nall called it one of "the most important climate variables for human comfort and building energy efficiency."DBT is an important variable in Psychrometrics, being the horizontal axis of a Psychrometric chart.Earth Observing System
The Earth Observing System (EOS) is a program of NASA comprising a series of artificial satellite missions and scientific instruments in Earth orbit designed for long-term global observations of the land surface, biosphere, atmosphere, and oceans. The satellite component of the program was launched in 1997. The program is centerpiece of NASA's Earth Science Enterprise (ESE).Global Sea Level Observing System
The Global Sea Level Observing System (GLOSS) is an Intergovernmental Oceanographic Commission program whose purpose is to measure sea level globally for long-term climate change studies. The program's purpose has changed since the 2004 Indian Ocean earthquake and the program now collects realtime measurements of sea level. The project is currently upgrading the over 290 stations it currently runs, so that they can send realtime data via satellite to newly set up national tsunami centres. They are also fitting the stations with solar panels so they can continue to operate even if the mains power supply is interrupted by severe weather. The Global Sea Level Observing System does not compete with Deep-ocean Assessment and Reporting of Tsunamis as most GLOSS transducers are located close to land masses while DART's transducers are far out in the ocean.Journal of the Atmospheric Sciences
The Journal of the Atmospheric Sciences (until 1962 titled Journal of Meteorology) is a scientific journal published by the American Meteorological Society. It covers basic research related to the physics, dynamics, and chemistry of the atmosphere of Earth and other planets, with emphasis on the quantitative and deductive aspects of the subject.MOPITT
MOPITT (Measurements of Pollution in the Troposphere) is a payload scientific instrument launched into Earth orbit by NASA on board the Terra satellite in 1999. It is designed to monitor changes in pollution patterns and its effect in the lower atmosphere of the Earth. The instrument was funded by the Space Science Division of the Canadian Space Agency.Mesoscale meteorology
Mesoscale meteorology is the study of weather systems smaller than synoptic scale systems but larger than microscale and storm-scale cumulus systems. Horizontal dimensions generally range from around 5 kilometers to several hundred kilometers. Examples of mesoscale weather systems are sea breezes, squall lines, and mesoscale convective complexes.
Vertical velocity often equals or exceeds horizontal velocities in mesoscale meteorological systems due to nonhydrostatic processes such as buoyant acceleration of a rising thermal or acceleration through a narrow mountain pass.Monthly Weather Review
The Monthly Weather Review is a peer-reviewed scientific journal published by the American Meteorological Society. It covers research related to analysis and prediction of observed and modeled circulations of the atmosphere, including technique development, data assimilation, model validation, and relevant case studies. This includes papers on numerical techniques and data assimilation techniques that apply to the atmosphere and/or ocean environment. The editor-in-chief is David M. Schultz (University of Manchester).National Weather Service Buffalo, New York
The National Weather Service Buffalo, New York is a local office of the National Weather Service responsible for monitoring weather conditions in western and north central New York State including Buffalo, Rochester, Geneva, Fulton, and Watertown.Overcast
Overcast or overcast weather, as defined by the World Meteorological Organization, is the meteorological condition of clouds obscuring at least 95% of the sky. However, the total cloud cover must not be entirely due to obscuring phenomena near the surface, such as fog.Overcast, written as "OVC" in the METAR observation, is reported when the cloud cover is observed to equal eight oktas (eighths). An overcast sky may be explicitly identified as thin (mostly transparent), but otherwise is considered opaque, which always constitutes a ceiling in aviation meteorology.Sometimes clouds can be different colors such as black or white, but overcast usually refers to darker skies. In some cases, it can be impossible to see distinct borders of clouds or the sky may be covered by a single type of cloud, such as stratus and the whole sky will be a dull white.
Periods of overcast weather can range from a few hours to several days. Overcast weather can also affect people suffering from seasonal affective disorder.
The same weather, when observed from above, might be referred to as (an) undercast.Rosenstiel School of Marine and Atmospheric Science
The Rosenstiel School of Marine and Atmospheric Science (RSMAS ) is a academic and research institution for the study of oceanography and the atmospheric sciences within the University of Miami (UM). It is located on a 16 acre (65,000 m²) campus on Virginia Key in Miami, Florida. It is the only subtropical applied and basic marine and atmospheric research institute in the continental United States.Up until 2008, RSMAS was solely a graduate school within the University of Miami, while it jointly administrated an undergraduate program with UM's College of Arts and Sciences. In 2008, the Rosenstiel School has taken over administrative responsibilities for the undergraduate program, granting Bachelor of Science in Marine and Atmospheric Science (BSMAS) and Bachelor of Arts in Marine Affairs (BAMA) baccalaureate degree. Master's, including a Master of Professional Science degree, and doctorates are also awarded to RSMAS students by the UM Graduate School.The Rosenstiel School's research includes the study of marine life, particularly Aplysia and coral; climate change; air-sea interactions; coastal ecology; and admiralty law. The school operates a marine research laboratory ship, and has a research site at an inland sinkhole. Research also includes the use of data from weather satellites and the school operates its own satellite downlink facility.Shortwave (meteorology)
A shortwave or shortwave trough is an embedded kink in the trough / ridge pattern. Its length scale is much smaller than that of longwaves, which are responsible for the largest scale (synoptic scale) weather systems. Shortwaves may be contained within or found ahead of longwaves and range from the mesoscale to the synoptic scale. Shortwaves are most frequently caused by either a cold pool or an upper level front.Snow grains
Snow grains are a form of precipitation. Snow grains are characterized as very small (<1 mm), white, opaque grains of ice that are fairly flat or elongated.
Unlike snow pellets, snow grains do not bounce or break up on impact. Usually, very small amounts fall, mostly from stratus clouds or fog, and never fall in the form of a shower.
The METAR code for snow grains is SG.The Weather Company
The Weather Company is a weather forecasting and information technology company that owns and operates weather.com, intellicast.com, and Weather Underground. The Weather Company is a subsidiary of the Watson & Cloud Platform business unit of IBM.Weather and Forecasting
Weather and Forecasting is a scientific journal published by the American Meteorological Society.
Articles on forecasting and analysis techniques, forecast verification studies, and case studies useful to forecasters. In addition, submissions that report on changes to the suite of operational numerical models and statistical post-processing techniques, and articles that demonstrate the transfer of research results to the forecasting community.Wind direction
Wind direction is reported by the direction from which it originates. For example, a northerly wind blows from the north to the south. Wind direction is usually reported in cardinal directions or in azimuth degrees. Wind direction is measured in degrees clockwise from due north. Consequently, a wind blowing from the north has a wind direction of 0°; a wind blowing from the east has a wind direction of 90°; a wind blowing from the south has a wind direction of 180°; and a wind blowing from the west has a wind direction of 270°. In general, wind directions are measured in units from 0° to 360°, but can alternatively be expressed from -180° to 180°.
Winds are named for the direction from which they come, followed by the suffix -erly. For example, winds from the north are called "northerly winds" (north + -erly).Windsock
A windsock is a conical textile tube which resembles a giant sock. Windsocks can be used as a basic guide to wind direction and speed, or as decoration.