scholarly journals ANALISIS PROFIL CAPE (CONVECTIVE AVAILABLE POTENTIAL ENERGY) SELAMA KEGIATAN INTENSIVE OBSERVATION PERIOD DI DRAMAGA BOGOR

2016 ◽  
Vol 17 (2) ◽  
pp. 83
Author(s):  
Alfan Muttaqin ◽  
Fikri Nur Muhammad ◽  
Purnomo Arif Abdillah
Keyword(s):  
Data Analysis ◽  
Potential Energy ◽  
Water Content ◽  
Liquid Water ◽  
Convective Available Potential Energy ◽  
Liquid Water Content ◽  
Moderate Intensity ◽  
Available Potential Energy ◽  
Intensive Observation ◽  
Altitude Level

IntisariProfil nilai CAPE(Convective Available Potential Energy) telah didapatkan dari analisis data Radiometer untuk wilayah Dramaga Kabupaten Bogor dan sekitarnya. Kegiatan pengamatan dilakukan dari tanggal 18 Januari – 16 Februari 2016. Radiometer mampu mengamati profil atmosfer sampai level ketinggian 10 km. Dengan kemampuan tersebut maka kandungan air (Liquid Water Content), kelembaban relatif (RH) dan suhu bisa teramati sampai level atas. Hasil pengolahan dan analisis menunjukkan bahwa nilai CAPE, sesaat akan terjadi hujan, cenderung terlihat turun dan bernilai mendekati 0 (nol). Ketika terjadi hujan dengan instensitas sedang maka nilai CAPE turun perlahan dan mendekati 0 (nol), ketika terjadi hujan dengan instensitas ringan maka nilai CAPE turun namun tidak mendekati 0 (nol) dan nilai CAPE ketika hari tidak hujan cenderung tidak ada yang mendekati 0 (nol). Besarnya nilai CAPE tidak berpengaruh terhadap intensitas curah hujan. Pada saat hari terjadi hujan maka akan disertai terjadinya penurunan nilai CAPE karena tidak ada konveksi.  AbstractCAPE value profile has been obtained from the Radiometer data analysis for Dramaga region and its surrounding. Observation activities conducted from January 18th to February 16th, 2016. Radiometer can observe atmospheric profiles up to 10 km altitude level. With this capability, the water content (Liquid Water Content), Relative Humidity (RH) and temperature can be measured up to 10 km. The results of processing and data analysis shows that the value of CAPE, just before the rain occur, tends to decline and approaching 0 (zero). When it rains with moderate intensity the value of CAPE decrease slowly and close to 0 (zero), when it rains with light intensity CAPE values is decrease but not close to 0 (zero) and CAPE value when it is not rain, tends to not approaching 0 (zero). The CAPE value does not affect the rain intensity. When the rain occurred, the CAPE value has been decrease because there is no convection..

scholarly journals Snow Wetness Measurement by Fluorescent Dye Dilution

1984 ◽  
Vol 30 (106) ◽  
pp. 362-363
Author(s):  
Robert E. Davis ◽  
Jeff Dozier
Keyword(s):  
Data Analysis ◽  
Water Content ◽  
Liquid Water ◽  
Equilibrium Temperature ◽  
Liquid Water Content ◽  
Fluorescent Dye ◽  
Dilution Method ◽  
Concentration Change ◽  
Dye Dilution ◽  
Snow Samples

AbstractThe fluorescent dye dilution method for determining the liquid-water content in snow is based on measuring the concentration change of a solution when it is mixed with snow. Samples for analysis can be obtained rapidly and reliably, and, unlike calorimetric or equilibrium-temperature methods, field use requires no on-site data analysis.

Influences of CAPE on Hail Production in Simulated Supercell Storms

2021 ◽  
Author(s):  
Yuzhu Lin ◽  
Matthew R. Kumjian
Keyword(s):  
Water Content ◽  
Residence Time ◽  
Liquid Water ◽  
Wind Field ◽  
Cloud Model ◽  
Convective Available Potential Energy ◽  
Horizontal Displacement ◽  
Liquid Water Content ◽  
Horizontal Wind ◽  
Supercell Storms

Abstract Lasting updrafts are necessary to produce severe hail; conventional wisdom suggests that extremely large hailstones require updrafts of commensurate strength. Because updraft strength is largely controlled by convective available potential energy (CAPE), one would expect environments with larger CAPE to be conducive to storms producing larger hail. By systematically varying CAPE in a horizontally homogeneous initial environment, we simulate hail production in high-shear, high-instability supercell storms using Cloud Model 1 and a detailed 3D hail growth trajectory model. Our results suggest that CAPE modulates the updraft’s strength, width, and horizontal wind field, as well as the liquid water content along hailstones’ trajectories, all of which have a significant impact on final hail sizes. In particular, hail sizes are maximized for intermediate CAPE values in the range we examined. Results show a non-monotonic relationship between the hailstones’ residence time and CAPE due to changes to the updraft wind field. The ratio of updraft area to southerly wind speed within the updraft serves as a proxy for residence time. Storms in environments with large CAPE may produce smaller hail because the in-updraft horizontal wind speeds become too great, and hailstones are prematurely ejected out of the optimal growth region. Liquid water content (LWC) along favorable hailstone pathways also exhibits peak values for intermediate CAPE values, owing to the horizontal displacement across the mid-level updraft of moist inflow air from differing source levels. In other words, larger CAPE does not equal larger hail, and storm-structural nuances must be examined.

scholarly journals Snow Wetness Measurement by Fluorescent Dye Dilution

1984 ◽  
Vol 30 (106) ◽  
pp. 362-363 ◽  
Author(s):  
Robert E. Davis ◽  
Jeff Dozier
Keyword(s):  
Data Analysis ◽  
Water Content ◽  
Liquid Water ◽  
Equilibrium Temperature ◽  
Liquid Water Content ◽  
Fluorescent Dye ◽  
Dilution Method ◽  
Concentration Change ◽  
Dye Dilution ◽  
Snow Samples

AbstractThe fluorescent dye dilution method for determining the liquid-water content in snow is based on measuring the concentration change of a solution when it is mixed with snow. Samples for analysis can be obtained rapidly and reliably, and, unlike calorimetric or equilibrium-temperature methods, field use requires no on-site data analysis.

scholarly journals Proof of Concept: Development of Snow Liquid Water Content Profiler Using CS650 Reflectometers at Caribou, ME, USA

Sensors ◽  
2017 ◽  
Vol 17 (3) ◽  
pp. 647 ◽  
Author(s):  
Carlos Pérez Díaz ◽  
Jonathan Muñoz ◽  
Tarendra Lakhankar ◽  
Reza Khanbilvardi ◽  
Peter Romanov
Keyword(s):  
Water Content ◽  
Liquid Water ◽  
Liquid Water Content ◽  
Concept Development ◽  
Proof Of Concept

Field Measurement of the Liquid-Water Content of Snow

1981 ◽  
Vol 27 (95) ◽  
pp. 175-178 ◽  
Author(s):  
E. M. Morris
Keyword(s):  
Water Content ◽  
Liquid Water ◽  
Field Measurement ◽  
Solution Method ◽  
Liquid Water Content ◽  
Field Trials

Abstract Field trials show that the liquid-water content of snow can be determined simply and cheaply by a version of Bader’s solution method.

scholarly journals Ocean Convective Available Potential Energy. Part II: Energetics of Thermobaric Convection and Thermobaric Cabbeling

2016 ◽  
Vol 46 (4) ◽  
pp. 1097-1115 ◽  
Author(s):  
Zhan Su ◽  
Andrew P. Ingersoll ◽  
Andrew L. Stewart ◽  
Andrew F. Thompson
Keyword(s):  
Potential Energy ◽  
Deep Convection ◽  
Center Of Mass ◽  
Convective Available Potential Energy ◽  
Vertical Mixing ◽  
Available Potential Energy ◽  
Energy Part ◽  
Different Temperatures ◽  
Simplifying Assumptions ◽  
Diabatic Processes

AbstractThe energetics of thermobaricity- and cabbeling-powered deep convection occurring in oceans with cold freshwater overlying warm salty water are investigated here. These quasi-two-layer profiles are widely observed in wintertime polar oceans. The key diagnostic is the ocean convective available potential energy (OCAPE), a concept introduced in a companion piece to this paper (Part I). For an isolated ocean column, OCAPE arises from thermobaricity and is the maximum potential energy (PE) that can be converted into kinetic energy (KE) under adiabatic vertical parcel rearrangements. This study explores the KE budget of convection using two-dimensional numerical simulations and analytical estimates. The authors find that OCAPE is a principal source for KE. However, the complete conversion of OCAPE to KE is inhibited by diabatic processes. Further, this study finds that diabatic processes produce three other distinct contributions to the KE budget: (i) a sink of KE due to the reduction of stratification by vertical mixing, which raises water column’s center of mass and thus acts to convert KE to PE; (ii) a source of KE due to cabbeling-induced shrinking of the water column’s volume when water masses with different temperatures are mixed, which lowers the water column’s center of mass and thus acts to convert PE into KE; and (iii) a reduced production of KE due to diabatic energy conversion of the KE convertible part of the PE to the KE inconvertible part of the PE. Under some simplifying assumptions, the authors also propose a theory to estimate the maximum depth of convection from an energetic perspective. This study provides a potential basis for improving the convection parameterization in ocean models.

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