Appendix C • Notation

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Appendix C • Notation Copyright © 2018 by Roland Stull. Practical Meteorology: An Algebra-based Survey of Atmospheric Science. v1.03 APPENDIX C • NOTATION Compiled by Alison Deere and Marjolein Ribberink University of British Columbia. Contents AVCS arbitrary vertical cross-section CB Bernoulli’s constant Aw global albedo corresponding to an atmo- CC cell circulation Roman Symbols, Acronyms & Contractions C881 spheric window cloud-to-cloud Greek Symbols C885 AWOS automatic weather observing system CCD charge-coupled devices Operators C887 AZ Arizona, USA postal code CCL convective condensation level Superscripts C887 a acceleration CCN cloud condensation nuclei Subscripts C887 attenuation coefficient CD drag coefficient Special Symbols C887 length of semi-major axis of earth’s orbit fraction of the globe covered by dark dai- = 149.457 Gm sies parameter or constant (varies by context) CF coriolis force spillage distance of front CFL Courant-Friedrichs-Lewy (condition for (= external Rossby radius of deforma- numerical stability) tion) CG cloud-to-ground surface albedo CG fractional area covered by bare ground a vector acceleration CH bulk heat-transfer coefficient aH mixed-layer transport coefficient = 0.0063 CH4 methane ROMAN SYMBOLS, arccos inverse of cosine function (cos–1) CI capping inversion arcsin inverse of sine function (sin–1) CIN convective inhibition ACRONYMS & arctan inverse of tangent function (tan–1) CL classic –1 asin inverse of sine function (sin ) CL fraction of the globe covered by light dai- CONTRACTIONS atm atmospheres (a pressure unit) sies aλ absorptivity CMC Canadian Meteorological Center CO carbon monoxide Colorado, USA postal code A CO2 carbon dioxide A advection of TKE B CP cumulative probability albedo B Beaufort wind scale Cp specific heat of air at constant pressure ampere (a unit of electrical current) bias score Cpd specific heat of dry air at constant pressure amplitude bowen ratio = 1004.67 J·kg–2·K–1 area breakdown potential for dry air Cpv specific heat for water vapor at constant Ball ratio = 0.2 = 3x109 V km–1 pressure = 1875 J·kg–1·K–1 initial analysis buoyant production or consumption of Cr relative circulation north-south amplitude of a wave TKE CRT video screen. Literally: Cathode Ray Tube parameter or constant (varies by context) BC boundary conditions Cs seed coverage AAM absolute angular momentum British Columbia, Canada postal code CSI critical sucess index AB Alberta, Canada postal code BLG boundary-layer gradient (wind) CT Connecticut, USA postal code ABL Atmospheric Boundary Layer BRN bulk richardson number Cu cumulus cloud ACARS aircraft communication and reporting BSS Brier Skill Score Curv curvature system Bλ black-body radiation of a certain wave- Cv specific heat at constant volume AD albedo of dark-colored daisies length Cvd air specific heat of dry air at constant volume AG albedo of bare ground parameter or constant (varies by context) Cw vertical drag coefficient AGL above ground level b absorption cross section Cy dimensionless cross-wind integrated con- AIREP aviation report damping factor centration AK Alaska, USA postal code extinction cross section °C degrees Celsius or centigrade, a unit of AL Alabama, USA postal code length of semi-minor axis = 149.090 Gm temperature AL albedo of light-colored daisies parameter or constant (varies by context) c concentration of a pollutant AMDAR aircraft meteorological data relay b1 parameter or constant (varies by context) density correction factor AO Arctic Oscillation bD dimensionless coefficient half the distance between two foci of an AR Arkansas, USA postal code bH convective transport coefficient ellipse Ar argon maximum concentration ARPEGE Action de Recherche Petite Echelle Grande parameter or constant (varies by context) Echelle (weather-forecast model) phase speed or shallow-water wave ASDAR aircraft to satellite data relay C speeds ASOS automatic surface observing system C angular rotation in a full circle (360° or 2π speed of light through air at sea level pres- AT apparent temperature (heat index) radians) sure = 299,710,000 m·s–1 circle circumference (360° or 2π radians) speed of sound circulation c0 speed of light in a vacuum = 299,792,258 climatological condition m·s–1 cost c1 parameter or constant (varies by context) dimensionless concentration c parameter or constant (varies by context) “Practical Meteorology: 2 fractional area covered c3 parameter or constant (varies by context) An Algebra-based Survey parameter or constant (varies by context) c4 parameter or constant (varies by context) of Atmospheric Science” specific heat capacity cd “candela, a unit of luminous intensity” by Roland Stull is licensed under a Creative CA air discharge cg group speed or group velocity Commons Attribution-NonCommercial-Sha- California, USA postal code ci speed of light through medium i reAlike 4.0 International License. View this Ca absolute circulation cm centimeter, a length unit license at http://creativecommons.org/ CAN Canada cos cosine licenses/by-nc-sa/4.0/ . This work is avail- CAPE Convective Available Potential Energy covar covariance able at https://www.eoas.ubc.ca/books/ CAPPI constant altitude plan position indicator cP continental polar air mass Practical_Meteorology/ CAT clear-air turbulence cy crosswind-integrated concentration C881 C882 NOTATION –2 cαβ intermediate calculation parameter for at- Eϕ incoming or outgoing radiative flux at lat- of W·m ) mospheric optical ray paths itude ϕ FH sensible heat flux from earth’s surface up E average daily insolation into the air (in dynamic units W·m–2) E’ coalescence efficiency Frad* net radiative flux E* total irradiance Fx dynamic heat flux in x direction D E*λ emittance/radiant existence/irradiance Fy dynamic heat flux in y direction D daylight duration hours irradiance at wavelength λ Fz dynamic heat flux in z direction death rate of daisies e base of natural logarithms = 2.7182818285 f oscillation frequency diffusivity = 2.11x10–5 m2·s–1 for water va- current or voltage feedback factor por in air under standard conditions eccentricity fc Coriolis parameter distance eccentricity of earth’s orbit = 0.0167 centrifugal force drop diameter vapor pressure fG pull (force) by earth’s gravity duration of positive heat flux e0 saturation vapor pressure = 0.611 kPa at f0 reference Coriolis parameter at the center fractal dimension 0 °C of the beta plane modern description eIR IR surface emissivity ft feet, a length unit parameter or constant (varies by context) es saturation vapor pressure over flat pure ft H2O feet of water, a pressure unit water fx fraction of cloud sizes precipitation duration (h) saturation vapor pressure Fz eff sfc effective surface heat flux size of particle es* actual saturation vapor pressure width of flow ew equilibrium emissivity corresponding to DA data assimilation an atmospheric window DC District of Columbia, USA postal code exp base of natural logarithms = 2.7182818285 G DE Delaware, USA postal code eλ emissivity at wavelength λ G cyclone graveyard DIAL differential absorption lidars gain DJF “December, January, and February” geostrophic wind speed DMSP defense meterological satellite program gravitational constant DT Daylight Savings Time F = 6.67x10–11 m3·s–2·kg–1 DW diabatic warming rate F flux density intermediate circulation parameter Dφ differential heating kinematic flux theoretical geostrophic value Dϕ net radiative flux, or differential heating, false-alarm rate GA Georgia, USA postal code at latitude ϕ force GB gigabyte d days, a time unit forecast GCM global climate model depth Fujita tornado damage scale GCM general circulation model diagonal length F vector force GEM Global Environmental Multiscale (Cana- distance between crest and trough of a FA free atmosphere dian numerical model) wave FAR false-alarm ratio GFS Global Forecast System distance between earth and sun = 149.6 FAS Federation of American Scientists GHG greenhouse gas Gm Fc tracer flux Gm gigameter, a length unit Julian day FCF Coriolis force Gm gap-geostrophic wind plume spread FCN centrifugal force GMT Greenwich Mean Time thickness FE latent heat flux from earth’s surface up GPS global positioning system (via satellite) dmax.rain total accumulated depth in a rain gauge into the air (in kinematic units of GPU Graphics Processing Unit –1 dr Julian day of summer solstice = 173 K·m·s ) GSM global spectral model dw precipitable water FFD Forward flank downdraft GSS Gilbert’s skill score dy number of days in a year FG flux gradient GTS global telecommunication system dBZ decibels of Z - units of radar reflectivity FG molecular heat conduction g grams, a unit of mass ∆d phase shift heat flux conducted from the ground up to gravitational acceleration = –9.8 m·s–2 the earth’s surface (in kinematic units (negative means downward) of K·m·s –1) g’ reduced gravity FH sensible heat flux from earth’s surface up E into the air (in kinematic units of E collision efficiency K·m·s –1) East FHsfc surface kinematic heat flux H H geopotential height efficiency FL Florida, USA postal code electric field Fnet net vector force high pressure center energy FNMOC Fleet Numerical Meteorological and high incoming or outgoing radiative flux Oceanographic Center hit rate irradiance FPG Pressure gradient force heating rate turbine efficiency FPGm mesoscale pressure-gradient force helicity E0 theoretical efficiency FPGs synoptic pressure-gradient force unperturbed ocean depth E1 parameter or constant (varies by context) Fr Froude number H2 hydrogen Ec collection efficiency Frad radiative flux at a surface H2O
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