Weather terms starting with C

325 terms

C Abbreviation for cytosine.
C AMS Continental Air Mass
CA Cloud-to-Air lightning.
CAA Cold Air Advection
CAD Coronary artery disease. A disease in which there is a narrowing or blockage of the coronary arteries (blood vessels that carry blood and oxygen to the…
CADAS Centralized Automated Data Acquisition System - a system of two minicomputers in NWSH.
Calcite Light-colored mineral composed of calcium carbonate that often fills veins in igneous rocks and forms the sedimentary rock limestone.
calcium carbonate (CaCO<sub>3</sub>) A molecule consisting of calcium, carbon and oxygen that is secreted by corals, mollusks (clams, oysters, etc), foraminifera and other organisms to form a…
Calibration the set of operations which establish, under specified conditions, the relationship between values indicated by a measuring instrument or measuring…
CALM A weather condition when no air motion (wind) is detected.
calving separating or breaking so that a part becomes detached, as in icebergs separating from ice sheets.
Canyon Wind A foehn wind that is channeled through a canyon as it descends the lee side of a mountain barrier.
Cap A cap is a ceiling, or the highest level to which something can go. For example, an interest rate cap limits the amount by which an interest rate can be…
Cap Cloud A stationary cloud directly above an isolated mountain peak, with cloud base below the elevation of the peak.
CAPE Convective Available Potential Energy. A measure of the amount of energy available for convection.
Capillarity (1) The degree to which a material or object containing minute openings or passages, when immersed in a liquid, will draw the surface of the liquid above…
Capillary Fringe The soil area just above the water table where water can rise up slightly through the cohesive force of capillary action.
Capillary Waves Waves caused by the initial wind stress on the water surface causes what are known as capillary waves. These have a wavelength of less than 1.
Capillary Zone The soil area just above the water table where water can rise up slightly through the cohesive force of capillary action.
Capping A region of negative buoyancy below an existing level of free convection (LFC) where energy must be supplied to the parcel to maintain its ascent.
Capping Inversion Alternate term for Cap; a layer of relatively warm air aloft, usually several thousand feet above the ground, which suppresses or delays the development…
CAPS See: cleaved amplified polymorphic sequence.
Carbon black An amorphous form of carbon, produced commercially by thermal or oxidative decomposition of hydrocarbons and used principally in rubber goods, pigments…
Carbon Cycle All parts (reservoirs) and fluxes of carbon. The cycle is usually thought of as four main reservoirs of carbon interconnected by pathways of exchange.
Carbon Dioxide (KAR-bun dy-OK-side) A colorless, odorless gas. It is a waste product made by the body.
carbon dioxide concentration The amount of carbon dioxide, a heavy, colorless greenhouse gas, per unit of volume.
Carbon Dioxide Equivalent A metric measure used to compare the emissions from various greenhouse gases based upon their global warming potential (GWP).
Carbon Dioxide Fertilization The enhancement of the growth of plants as a result of increased atmospheric CO2 concentration.
carbon dioxide flux The rate of flow for carbon dioxide, a heavy, colorless greenhouse gas.
Carbon Equivalent A metric measure used to compare the emissions of different greenhouse gases based upon their global warming potential (GWP).
Carbon Intensity The amount of carbon by weight emitted per unit of energy consumed. A common measure of carbon intensity is weight of carbon per British thermal unit…
Carbon pool The reservoir containing carbon as a principal element in the geochemical cycle.
Carbon Sequestration The absorption and storage of carbon dioxide from the atmosphere. Naturally-occurring in plants.
Carbon sinks Carbon reservoirs and conditions that take-in and store more carbon (i.e., carbon sequestration) than they release.
Carbon tetrachloride A compound consisting of one carbon atom and four chlorine atoms. It is an ozone depleting substance.
Carrington Longitude A system of fixed longitudes rotating with the sun
Catalina Eddy A Catalina Eddy (coastal eddy) forms when upper level large-scale flow off Point Conception interacts with the complex topography of the Southern…
Catchment Area An area having a common outlet for its surface runoff (also see Drainage Area or Basin, Watershed).
Categorical A National Weather Service precipitation descriptor for a 80, 90, or 100 percent chance of measurable precipitation (0.01 inch).
CAVU Clear or Scattered Clouds (visibility greater than 10 mi.)
CB Cumulonimbus cloud, characterized by strong vertical development in the form of mountains or huge towers topped at least partially by a smooth, flat…
CBMAM Cumulonimbus Mamma
CC Cloud-to-Cloud Lightning
CCITT Consultative Committee for International Telephone & Telegraphy. Sets standards for phones, faxes, modems etc.
CCL Convective Condensation Level- The level in the atmosphere to which an air parcel, if heated from below, will rise dry adiabatically, without becoming…
CD a type of form designation such as Form CD435, meaning a Commerce Department form
CDB Computing Development Branch (NCEP)
CDC Climate Diagnostic Center, the mission of the Climate Diagnostics Center (CDC) is to advance national capabilities to interpret the causes of observed…
CDD Cooling Degree Days- A form of degree day used to estimate energy requirements for air conditioning or refrigeration.
CDFNT Cold Front
CDT Central Daylight Time
Ceiling If there is an upper limit, or cap, on the interest rate you can be charged on an adjustable-rate loan, it's known as a ceiling.
Ceilometer A device using a laser or other light source to determine the height of a cloud base.
Cell The fundamental level of structural organization in complex organisms. Eukaryotic cells contain a nucleus (with chromosome s) and cytoplasm with the…
Celsius The standard scale used to measure temperature in most areas outside the United States.
CEM Civil Emergency Message. A message issued by the National Weather Service in coordination with Federal, state or local government to warn the general…
Center Generally speaking, the vertical axis of a tropical cyclone, usually defined by the location of minimum wind or minimum pressure.
Center / Vortex Fix The location of the center of a tropical or subtropical cyclone obtained by reconnaissance aircraft penetration, satellite, radar, or synoptic data.
Centimeter Burst A solar radio burst in the centimeter wavelength range.
Central Meridian Passage (CMP) In solar-terrestrial terms, the passage of an Active Region or other feature across the longitude meridian that passes through the apparent center of the…
Central North Pacific Basin The region north of the Equator between 140W and the International Dateline. The Central Pacific Hurricane Center (CPHC) in Honolulu, Hawaii is…
centrifugal force A force directed outward, away from the center of a rotating object; equal in magnitude to the centripetal force but in the opposite direction.
centripetal force An inward-directed force that confines an object to a circular path and is equal in magnitude to the centrifugal force but in the opposite direction.
CENTROID The center of mass of a storm.
CFC See Consumption of fixed capital (CFC)
CFP Cold Front Passage
CFS core financial system
Cfs-Day The volume of water discharged in twenty four hours, with a flow of one cubic foot per second is widely used; 1 cfs-day is 24 x 60 x 60 = 86,000 cubic…
CG Cloud-to-Ground Lightning
Chance A National Weather Service precipitation descriptor for 30, 40, or 50 percent chance of measurable precipitation (0.01 inch).
Channel The bed of a stream or river. This can also refer to a submerged stream or river channel in a reservoir.
Channel Inflow Water, which at any instant, is flowing into the channel system form surface flow, subsurface flow, base flow, and rainfall that has directly fallen onto…
Channel Lead An elongated opening in the ice cover caused by a water current.
Channel Routing The process of determining progressively timing and shape of the flood wave at successive points along a river.
Channeled High Winds In mountainous areas or in cities with tall buildings, air may be channeled through constricted passages producing high winds.
Channelization The modification of a natural river channel; may include deepening, widening, or straightening.
chaotic impossible to predict.
Charles' law With constant pressure, the temperature of an ideal gas is inversely proportional to the density of the gas.
CHC Chance
Chemical reaction Interaction between chemicals in which there is a change in the chemical composition of the elements or compounds involved.
Chemistry Model A computer model used in air pollution investigations that simulates chemical and photochemical reactions of the pollutants during their transport and…
CHG Change
CHGS changes
Chinook This is a region-specific term used for Foehn Winds in the lee of the Rocky Mountains in the United States; Foehn Winds are warm, dry winds that occur in…
Chinook Arch A foehn cloud formation appearing as a bank of altostratus clouds east of the Rocky Mountains, heralding the approach of a chinook.
Chlorofluorocarbons (CFCs) - Manufactured substances used as coolants and computer-chip cleaners. When these products break down they destroy stratospheric ozone, creating…
Chromosphere 2,500 km thick (1,600 mi) layer of plasma above the Sun’s photosphere. Temperatures range from ~4500 K to 60,000 K (110,000 to 8,000°F).
Chromospheric Events In solar-terrestrial terms, flares that are just Chromospheric Events without Centimetric Bursts or Ionospheric Effects. (SID) (Class C flare)
chronology a general term for the age-depth relationship in ice, sediment, or another deposit.
CI Cirrus clouds- High-level clouds (16,000 feet or higher), composed of ice crystals and appearing in the form of white, delicate filaments or white or…
CIG Ceiling- The height of the lowest layer of clouds, when the sky is broken or overcast.
CIN Growth of abnormal cells on the surface of the cervix. Numbers from 1 to 3 may be used to describe how abnormal the cells are and how much of the cervical…
CIO Chief Information Officer
Circulation (ser-kyoo-LAY-shun) In the body, the flow of blood through the heart and blood vessels, and the flow of lymph through the lymph vessels.
Circumpolar vortex Circumpolar vortex The large-scale cyclonic circulation in the middle and upper troposphere centered generally in the polar region.
Cirriform High altitude ice clouds with a very thin wispy appearance.
Cirrocumulus A cirriform cloud characterized by thin, white patches, each of which is composed of very small granules or ripples.
Cirrostratus A cloud of a class characterized by a composition of ice crystals and often by the production of halo phenomena and appearing as a whitish and usually…
Cirrus (abbrev. CI) High-level clouds (16,000 feet or higher), composed of ice crystals and appearing in the form of white, delicate filaments or white or mostly…
Civil Dawn The time of morning at which the sun is 6 degrees below the horizon. At this time, there is enough light for objects to be distiguishable and that outdoor…