求助：FNL数据中cape180_0mb:等变量的具体含义

海蓝蓝

求助：FNL数据中Best (4 layer) Lifted Index 等变量的具体含义

本人学海洋多一点，气象不怎么懂。昨天折腾一天，把下载的 FNL 1*1deg. data (e.g., "fnl_20110428_12_00")用GrADS解码画图，发现ctl文件中对变量描述语焉不详，查了一通资料也没发现线索，发email问FNL网站负责人Doug，他也没给明确答复。这里高人多，用FNL资料的也多，特来求助。下面是我感兴趣的几个index，谁知道其具体含义呢？最好的给出定义，或者给点参考资料，先谢过！
（下面的描述取自ctl文件，为什么里面总有个none呢？）
(1)no4lftxsfc: surface none Best (4 layer) Lifted Index [K]
(2)capesfc: surface none CAPE [J/kg]
(3)cape180_0mb: 180-0 mb above ground none CAPE [J/kg]
(4)cinsfc: surface none Convective Inhibition [J/kg]
(5)cin180_0mb: 180-0 mb above ground none CI[J/kg]
(6)lftxsfc: surface none Surface Lifted Index [K]
(7)prmslmsl: mean sea level none Pressure Reduced to MSL

------------
附件：这是全部138个变量列表。供参考。
File 1 : fnl_20110428_12_00
  Descriptor: fnl_20110428_12_00.ctl
  Binary: fnl_20110428_12_00
  Type = Gridded
  Xsize = 360  Ysize = 181  Zsize = 26  Tsize = 1  Esize = 1

  Number of Variables = 138
     no4lftxsfc  0  0,7,193  ** surface none Best (4 layer) Lifted Index [K]
     no5wava500mb  0  0,3,197  ** 500 mb none 5-Wave Geopotential Height Anomaly
[gpm]
     no5wavh500mb  0  0,3,193  ** 500 mb none 5-Wave Geopotential Height [gpm]
     absvprs  26  0,2,10  ** (1000 975 950 925 900 850 800 750 700 650 600 550 5
00 450 400 350 300 250 200 150 100 70 50 30 20 10) none Absolute Vorticit
     acpcpsfc  0  0,1,10,1  ** surface acc Convective Precipitation [kg/m^2]
     albdosfc  0  0,19,1,0  ** surface ave Albedo [%]
     apcpsfc  0  0,1,8,1  ** surface acc Total Precipitation [kg/m^2]
     capesfc  0  0,7,6  ** surface none Convective Available Potential Energy [J
/kg]
     cape180_0mb  0  0,7,6  ** 180-0 mb above ground none Convective Available P
otential Energy [J/kg]
     cfrzrsfc  0  0,1,193,0  ** surface ave Categorical Freezing Rain (yes=1; no
=0) [non-dim]
     cicepsfc  0  0,1,194,0  ** surface ave Categorical Ice Pellets (yes=1; no=0
) [non-dim]
     cinsfc  0  0,7,7  ** surface none Convective Inhibition [J/kg]
     cin180_0mb  0  0,7,7  ** 180-0 mb above ground none Convective Inhibition [
J/kg]
     clwmrprs  21  0,1,22  ** (1000 975 950 925 900 850 800 750 700 650 600 550
500 450 400 350 300 250 200 150 100) none Cloud Mixing Ratio [kg/kg]
     cpratsfc  0  0,1,196,0  ** surface ave Convective Precipitation Rate [kg/m^
2/s]
     crainsfc  0  0,1,192,0  ** surface ave Categorical Rain (yes=1; no=0) [non-
dim]
     csnowsfc  0  0,1,195,0  ** surface ave Categorical Snow (yes=1; no=0) [non-
dim]
     cwatclm  0  0,6,6  ** entire atmosphere (considered as a single layer) none
Cloud Water [kg/m^2]
     cworkclm  0  0,6,193,0  ** entire atmosphere (considered as a single layer)
ave Cloud Work Function [J/kg]
     dlwrfsfc  0  0,5,192,0  ** surface ave Downward Long-Wave Rad. Flux [W/m^2]
     dswrfsfc  0  0,4,192,0  ** surface ave Downward Short-Wave Rad. Flux [W/m^2
]
     gfluxsfc  0  2,0,193,0  ** surface ave Ground Heat Flux [W/m^2]
     gpa1000mb  0  0,3,9  ** 1000 mb none Geopotential Height Anomaly [gpm]
     gpa500mb  0  0,3,9  ** 500 mb none Geopotential Height Anomaly [gpm]
     hgtsfc  0  0,3,5  ** surface none Geopotential Height [gpm]
     hgtprs  26  0,3,5  ** (1000 975 950 925 900 850 800 750 700 650 600 550 500
450 400 350 300 250 200 150 100 70 50 30 20 10) none Geopotential Heig
     hgtneg2pv  0  0,3,5  ** PV=-2e-06 (Km^2/kg/s) surface none Geopotential Hei
ght [gpm]
     hgt2pv  0  0,3,5  ** PV=2e-06 (Km^2/kg/s) surface none Geopotential Height
[gpm]
     hgttop0c  0  0,3,5  ** highest tropospheric freezing level none Geopotentia
l Height [gpm]
     hgt0c  0  0,3,5  ** 0C isotherm none Geopotential Height [gpm]
     hgtmwl  0  0,3,5  ** max wind none Geopotential Height [gpm]
     hgttrop  0  0,3,5  ** tropopause none Geopotential Height [gpm]
     hpblsfc  0  0,3,196  ** surface none Planetary Boundary Layer Height [m]
     icecsfc  0  10,2,0  ** surface none Ice Cover [Proportion]
     landsfc  0  2,0,0  ** surface none Land Cover (1=land, 0=sea) [Proportion]
     lftxsfc  0  0,7,192  ** surface none Surface Lifted Index [K]
     lhtflsfc  0  0,0,10,0  ** surface ave Latent Heat Net Flux [W/m^2]
     o3mrprs  26  0,14,192  ** (100 70 50 30 20 10) none Ozone Mixing Ratio [kg/
kg]
     pevprsfc  0  0,1,200  ** surface none Potential Evaporation Rate [W/m^2]
     potsig995  0  0,0,2  ** 0.995 sigma level none Potential Temperature [K]
     pratesfc  0  0,1,7,0  ** surface ave Precipitation Rate [kg/m^2/s]
     pressfc  0  0,3,0  ** surface none Pressure [Pa]
     presmsl  0  0,3,0  ** mean sea level none Pressure [Pa]
     presneg2pv  0  0,3,0  ** PV=-2e-06 (Km^2/kg/s) surface none Pressure [Pa]
     pres2pv  0  0,3,0  ** PV=2e-06 (Km^2/kg/s) surface none Pressure [Pa]
     preslclb  0  0,3,0,0  ** low cloud bottom level ave Pressure [Pa]
     preslclt  0  0,3,0,0  ** low cloud top level ave Pressure [Pa]
     presmclb  0  0,3,0,0  ** middle cloud bottom level ave Pressure [Pa]
     presmclt  0  0,3,0,0  ** middle cloud top level ave Pressure [Pa]
     preshclb  0  0,3,0,0  ** high cloud bottom level ave Pressure [Pa]
     preshclt  0  0,3,0,0  ** high cloud top level ave Pressure [Pa]
     presmwl  0  0,3,0  ** max wind none Pressure [Pa]
     prestrop  0  0,3,0  ** tropopause none Pressure [Pa]
     prmslmsl  0  0,3,1  ** mean sea level none Pressure Reduced to MSL [Pa]
     pwatclm  0  0,1,3  ** entire atmosphere (considered as a single layer) none
Precipitable Water [kg/m^2]
     rhprs  21  0,1,1  ** (1000 975 950 925 900 850 800 750 700 650 600 550 500
450 400 350 300 250 200 150 100) none Relative Humidity [%]
     rh2m  0  0,1,1  ** 2 m above ground none Relative Humidity [%]
     rhsg330_1000  0  0,1,1  ** 0.33-1 sigma layer none Relative Humidity [%]
     rhsg440_1000  0  0,1,1  ** 0.44-1 sigma layer none Relative Humidity [%]
     rhsg720_940  0  0,1,1  ** 0.72-0.94 sigma layer none Relative Humidity [%]
     rhsg440_720  0  0,1,1  ** 0.44-0.72 sigma layer none Relative Humidity [%]
     rhsig995  0  0,1,1  ** 0.995 sigma level none Relative Humidity [%]
     rh30_0mb  0  0,1,1  ** 30-0 mb above ground none Relative Humidity [%]
     rhclm  0  0,1,1  ** entire atmosphere (considered as a single layer) none R
elative Humidity [%]
     rhtop0c  0  0,1,1  ** highest tropospheric freezing level none Relative Hum
idity [%]
     rh0c  0  0,1,1  ** 0C isotherm none Relative Humidity [%]
     shtflsfc  0  0,0,11,0  ** surface ave Sensible Heat Net Flux [W/m^2]
     soilw0_10cm  0  2,0,192  ** 0-0.1 m below ground none Volumetric Soil Moist
ure Content [Fraction]
     soilw10_40cm  0  2,0,192  ** 0.1-0.4 m below ground none Volumetric Soil Mo
isture Content [Fraction]
     soilw40_100cm  0  2,0,192  ** 0.4-1 m below ground none Volumetric Soil Moi
sture Content [Fraction]
     soilw100_200cm  0  2,0,192  ** 1-2 m below ground none Volumetric Soil Mois
ture Content [Fraction]
     spfh2m  0  0,1,0  ** 2 m above ground none Specific Humidity [kg/kg]
     spfh30_0mb  0  0,1,0  ** 30-0 mb above ground none Specific Humidity [kg/kg
]
     tcdcclm  0  0,6,1,0  ** entire atmosphere (considered as a single layer) av
e Total Cloud Cover [%]
     tcdcblcll  0  0,6,1,0  ** boundary layer cloud layer ave Total Cloud Cover
[%]
     tcdclcll  0  0,6,1,0  ** low cloud layer ave Total Cloud Cover [%]
     tcdcmcll  0  0,6,1,0  ** middle cloud layer ave Total Cloud Cover [%]
     tcdchcll  0  0,6,1,0  ** high cloud layer ave Total Cloud Cover [%]
     tcdcccll  0  0,6,1  ** convective cloud layer none Total Cloud Cover [%]
     tmax2m  0  0,0,4  ** 2 m above ground missing Maximum Temperature [K]
     tmin2m  0  0,0,5  ** 2 m above ground missing Minimum Temperature [K]
     tmpsfc  0  0,0,0  ** surface none Temperature [K]
     tmpprs  26  0,0,0  ** (1000 975 950 925 900 850 800 750 700 650 600 550 500
450 400 350 300 250 200 150 100 70 50 30 20 10) none Temperature [K]
     tmp_1829m  0  0,0,0  ** 1829 m above mean sea level none Temperature [K]
     tmp_2743m  0  0,0,0  ** 2743 m above mean sea level none Temperature [K]
     tmp_3658m  0  0,0,0  ** 3658 m above mean sea level none Temperature [K]
     tmp2m  0  0,0,0  ** 2 m above ground none Temperature [K]
     tmpsig995  0  0,0,0  ** 0.995 sigma level none Temperature [K]
     tmp0_10cm  0  0,0,0  ** 0-0.1 m below ground none Temperature [K]
     tmp10_40cm  0  0,0,0  ** 0.1-0.4 m below ground none Temperature [K]
     tmp40_100cm  0  0,0,0  ** 0.4-1 m below ground none Temperature [K]
     tmp100_200cm  0  0,0,0  ** 1-2 m below ground none Temperature [K]
     tmp30_0mb  0  0,0,0  ** 30-0 mb above ground none Temperature [K]
     tmpneg2pv  0  0,0,0  ** PV=-2e-06 (Km^2/kg/s) surface none Temperature [K]
     tmp2pv  0  0,0,0  ** PV=2e-06 (Km^2/kg/s) surface none Temperature [K]
     tmplclt  0  0,0,0,0  ** low cloud top level ave Temperature [K]
     tmpmclt  0  0,0,0,0  ** middle cloud top level ave Temperature [K]
     tmphclt  0  0,0,0,0  ** high cloud top level ave Temperature [K]
     tmpmwl  0  0,0,0  ** max wind none Temperature [K]
     tmptrop  0  0,0,0  ** tropopause none Temperature [K]
     tozneclm  0  0,14,0  ** entire atmosphere (considered as a single layer) no
ne Total Ozone [Dobson]
     ugwdsfc  0  0,3,194,0  ** surface ave Zonal Flux of Gravity Wave Stress [N/
m^2]
     uflxsfc  0  0,2,17,0  ** surface ave Momentum Flux, U-Component [N/m^2]
     ugrdprs  26  0,2,2  ** (1000 975 950 925 900 850 800 750 700 650 600 550 50
0 450 400 350 300 250 200 150 100 70 50 30 20 10) none U-Component of Wi
     ugrd_1829m  0  0,2,2  ** 1829 m above mean sea level none U-Component of Wi
nd [m/s]
     ugrd_2743m  0  0,2,2  ** 2743 m above mean sea level none U-Component of Wi
nd [m/s]
     ugrd_3658m  0  0,2,2  ** 3658 m above mean sea level none U-Component of Wi
nd [m/s]
     ugrd10m  0  0,2,2  ** 10 m above ground none U-Component of Wind [m/s]
     ugrdsig995  0  0,2,2  ** 0.995 sigma level none U-Component of Wind [m/s]
     ugrd30_0mb  0  0,2,2  ** 30-0 mb above ground none U-Component of Wind [m/s
]
     ugrdneg2pv  0  0,2,2  ** PV=-2e-06 (Km^2/kg/s) surface none U-Component of
Wind [m/s]
     ugrd2pv  0  0,2,2  ** PV=2e-06 (Km^2/kg/s) surface none U-Component of Wind
[m/s]
     ugrdmwl  0  0,2,2  ** max wind none U-Component of Wind [m/s]
     ugrdtrop  0  0,2,2  ** tropopause none U-Component of Wind [m/s]
     ulwrfsfc  0  0,5,193,0  ** surface ave Upward Long-Wave Rad. Flux [W/m^2]
     ulwrftoa  0  0,5,193,0  ** top of atmosphere ave Upward Long-Wave Rad. Flux
[W/m^2]
     uswrfsfc  0  0,4,193,0  ** surface ave Upward Short-Wave Rad. Flux [W/m^2]
     uswrftoa  0  0,4,193,0  ** top of atmosphere ave Upward Short-Wave Rad. Flu
x [W/m^2]
     vgwdsfc  0  0,3,195,0  ** surface ave Meridional Flux of Gravity Wave Stres
s [N/m^2]
     vflxsfc  0  0,2,18,0  ** surface ave Momentum Flux, V-Component [N/m^2]
     vgrdprs  26  0,2,3  ** (1000 975 950 925 900 850 800 750 700 650 600 550 50
0 450 400 350 300 250 200 150 100 70 50 30 20 10) none V-Component of Wi
     vgrd_1829m  0  0,2,3  ** 1829 m above mean sea level none V-Component of Wi
nd [m/s]
     vgrd_2743m  0  0,2,3  ** 2743 m above mean sea level none V-Component of Wi
nd [m/s]
     vgrd_3658m  0  0,2,3  ** 3658 m above mean sea level none V-Component of Wi
nd [m/s]
     vgrd10m  0  0,2,3  ** 10 m above ground none V-Component of Wind [m/s]
     vgrdsig995  0  0,2,3  ** 0.995 sigma level none V-Component of Wind [m/s]
     vgrd30_0mb  0  0,2,3  ** 30-0 mb above ground none V-Component of Wind [m/s
]
     vgrdneg2pv  0  0,2,3  ** PV=-2e-06 (Km^2/kg/s) surface none V-Component of
Wind [m/s]
     vgrd2pv  0  0,2,3  ** PV=2e-06 (Km^2/kg/s) surface none V-Component of Wind
[m/s]
     vgrdmwl  0  0,2,3  ** max wind none V-Component of Wind [m/s]
     vgrdtrop  0  0,2,3  ** tropopause none V-Component of Wind [m/s]
     vvelprs  21  0,2,8  ** (1000 975 950 925 900 850 800 750 700 650 600 550 50
0 450 400 350 300 250 200 150 100) none Vertical Velocity (Pressure) [Pa
     vvelsig995  0  0,2,8  ** 0.995 sigma level none Vertical Velocity (Pressure
) [Pa/s]
     vwshneg2pv  0  0,2,192  ** PV=-2e-06 (Km^2/kg/s) surface none Vertical spee
d sheer [1/s]
     vwsh2pv  0  0,2,192  ** PV=2e-06 (Km^2/kg/s) surface none Vertical speed sh
eer [1/s]
     vwshtrop  0  0,2,192  ** tropopause none Vertical speed sheer [1/s]
     watrsfc  0  2,0,5,1  ** surface acc Water Runoff [kg/m^2]
     weasdsfc  0  0,1,13  ** surface none Water Equivalent of Accumulated Snow D
epth [kg/m^2]

流行雨

《第33届中国气象学会年会 S1 灾害天气监测、分析与预报》2016年
对流有效位能的不同计算方法及其对比
张夏琨  朱跃建  郭品文  

美国全球预报系统(Global Forecast System,GFS)产品提供了两种不同类型的CAPE数据,第一种是SB-CAPE,变量名为"CAPEsfc",第二种用"CAPE180_0mb"表示,是一种将ML-CAPE和MU-CAPE结合的"最优CAPE"。为了分析比较CAPE180_0mb与CAPEsfc的差异,以及两种CAPE数据对降水的指示作用的差别,利用GFS产品中的CAPE资料和我国区域自动气象站降水观测资料对上述问题进行了研究。研究发现,当CAPE值较小时,CAPE180_0mb的值显著大于CAPEsfc的值;随着CAPE值的增大,CAPE180_0mb与CAPEsfc的差值减小并逐渐转为负值;当CAPE较大时,CAPE180_0mb的值显著小于CAPEsfc的值。通过统计分析还发现CAPE180_0mb与降水率的相关性显著优于CAPEsfc与降水率的相关性,且个例分析也证实了CAPE180_0mb对强降水的指示作用好于CAPEsfc。在CAPE180_0mb的计算过程中,采用了"平均层气块"的选取方法。平均层气块的选用可以缓解由于地表面混合比相对较高而对CAPE造成的影响。当边界层大气并非完全混合的时候(所谓"完全混合"是指温度递减率为绝热且混合比为常数),与采用地表面气块计算CAPE不同,使用"平均层气块"计算CAPE可以有效避免将CAPE值估算过高。而且,CAPE180_0mb的计算过程还选取了多个不同层次的平均层气块中最不稳定的一个作为最终的抬升气块。最不稳定气块的选用可以有效地避免由于近地面层出现逆温现象而对CAPE造成的影响。当地表面层的气温低于其上方空气的温度时,使用"最不稳定气块"计算CAPE,即选取温度廓线上拥有最大CAPE的气块作为抬升气块,其计算结果更加准确,可以有效避免将CAPE值估算过低。综上所述,与CAPEsfc相比,CAPE180_0mb对CAPE的估算更为符合实际大气的不稳定情形,可以称为最优CAPE(Best-CAPE)。将CAPE180_0mb应用于强降水预报,其指示效果比CAPEsfc更好,对强降水预报的改善有一定的帮助。

wade

海蓝蓝你是想分享什么资料？

海蓝蓝

wade 发表于 2012-1-18 11:42

                               
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海蓝蓝你是想分享什么资料？

发帖的时候，可选项不多 ，只好选这一项。

海蓝蓝

A variation of the lifted index is the "best lifted index" or "4-layer lifted index." In this version, initially the lifted index is found for a few levels between the surface and 1600m. Then the best (most unstable) lifted index value is kept. This is helpful when the surface lifted index may misrepresent the true instability (e.g. morning soundings).

易小凯

我也很想知道那个none是什么意思？
还有，为啥比湿的数据只有2个层次的？为何不想相对湿度那样，在标准等压面上都有数据呢？
不知道楼主解决这个问题了么？也请@mofangbao指教。

mofangbao

易小凯 发表于 2012-7-7 21:13

                               
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我也很想知道那个none是什么意思？
还有，为啥比湿的数据只有2个层次的？为何不想相对湿度那样，在标准等压 ...

介个我也还不知道。。。

易小凯

mofangbao 发表于 2012-7-7 21:56

                               
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介个我也还不知道。。。

好吧，我再咨询一下其他人

ygtqily

从http://rda.ucar.edu/datasets/ds083.2/#access下载的fnl资料处理出来的ctl为什么和版主发的不一样啊？
CAPEsfc  0 157,1,0  ** surface Convective Avail. Pot. Energy [J/kg]
CAPE180_0mb  0 157,116,46080 ** 180-0 mb above gnd Convective Avail. Pot. Energy [J/kg]
CINsfc  0 156,1,0  ** surface Convective inhibition [J/kg]
CIN180_0mb  0 156,116,46080 ** 180-0 mb above gnd Convective inhibition [J/kg]

宁小才

本人在用fnl资料里面的cape时，发现cpae比单站的值要小很多，是什么原因？

Smile鑫吖

mofangbao 发表于 2012-7-7 21:56

                               
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介个我也还不知道。。。

VWSH2pv  0,109,2e-06   0,2,192 ** PV=2e-06 (Km^2/kg/s) surface none Vertical speed sheer [1/s]
嘿嘿，我刚好碰到这个问题、、、
能不能请问一下那个 PV=2e-06 (Km^2/kg/s)到底代表啥？是与垂直风切变的高度有关系的值吗？？？