Objective Analysis of Constant Altitude Aircraft Measurements in Thunderstorm Inflow Regions

Fankhauser, J. C.; Biter, Cleon J.; Mohr, Carl G.; Vaughan, Robin L.

doi:10.1175/1520-0426(1985)002<0157:oaocaa>2.0.co;2

Cited by 10 publications

(3 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…But kinematic (horizontal wind field) variables also play an important role in convective development. Factors include convergence at low levels (Fankhauser et al 1985;Wilson et al 1992Wilson et al , 1998Kottmeier et al 2008;Kalthoff et al 2009); boundary layer moisture (Fabry 2006); vertical moisture variations and depth of moisture (Crook 1996;Lee et al 1991;Bluestein et al 1990); midlevel moisture, stability, and horizontal wave pattern (Carbone 1982;Murphey et al 2006); and the vertical wind shear and its interaction with a precipitation-generated cold pool (Rotunno et al 1988;Wilson et al 1998). Several of these parameters are utilized in this study.…”

Section: Atmospheric Factors That May Influence the Size Of Precipitamentioning

confidence: 99%

Relationships between Large Precipitating Systems and Atmospheric Factors at a Grid Scale

Chen

Liu

Mapes

2017

Journal of the Atmospheric Sciences

View full text Add to dashboard Cite

In this study, TRMM-observed precipitation in the tropics is decomposed according to the horizontal area of radar precipitation features, with special emphasis on large systems (rain area > 104 km2) that contribute roughly half of tropical rainfall. Statistical associations of rain-weighted radar precipitation feature (RPF) size distributions with atmospheric variables on the 1.5° grid of ERA-Interim data are explored. In one-predictor distributions, the association with total precipitable water vapor (TPWV) is the strongest, while relative humidity at low and midlevels and low-level wind shear are also positively related to large-RPF rain fraction. Standard CAPE and CIN variables computed from grid-mean thermodynamic profiles are only weakly related to the size of rain systems. Joint distributions over two variables are also reported. The relative importance of predictors varies over different regions. The eastern Pacific is distinctive for having large rain systems in environments with a moist boundary layer but a dry midtroposphere, with strong shallow wind shear and small CAPE. In contrast, the large-storm environment over the western Pacific is found to be moister in the whole troposphere, with relatively weaker wind shear and larger CAPE. Over tropical land, the Sahel and central Africa stand out as having a great fractional rainfall contributed by large RPFs. Their associated environment is characterized by lower TPWV but stronger shallow wind shear and larger CIN and CAPE, in comparison to the equatorial Amazon basin and the Maritime Continent. Based on these associations, statistical reconstructions of the geographical distribution of large-RPF rain fraction from grid-mean atmospheric predictors are attempted.

show abstract

Section: Atmospheric Factors That May Influence the Size Of Precipitamentioning

confidence: 99%

Relationships between Large Precipitating Systems and Atmospheric Factors at a Grid Scale

Chen

Liu

Mapes

2017

Journal of the Atmospheric Sciences

View full text Add to dashboard Cite

show abstract

“…The vertical velocity data from the UW King Air were corrected for known biases obtained from intercomparison flights with the NCAR King Air and tower fly-bys, as done in Fankhauser et al (1985). This correction required a subtraction of 0.3 m s Ϫ1 for the UW King Air vertical velocity measurements.…”

Section: Thermodynamics and Dynamics Of The Environmentmentioning

confidence: 99%

Horizontal Convective Rolls: Determining the Environmental Conditions Supporting their Existence and Characteristics

et al. 1997

View full text Add to dashboard Cite

Data from the Convection and Precipitation/Electrification (CaPE) project, as well as results from numerical simulations, are used to study horizontal convective rolls. The environmental conditions necessary for sustaining rolls and for influencing the aspect ratio, ratio of roll wavelength to convective boundary layer (CBL) depth, and orientation are examined. Observations and numerical model simulations both suggest that a moderate surface sensible heat flux and some vertical wind shear are necessary for roll existence. Unlike some previous studies, however, it is shown that rolls occurred within very low CBL shear conditions (ϳ2 ϫ 10 Ϫ3 s Ϫ1). In addition, the low-level (i.e., ϳ200 m) shear seems to be more important than the shear through the depth of the CBL in roll sustenance. The aspect ratio is shown to be proportional to the CBL instability, measured in terms of the Monin-Obukhov length. The roll orientation is similar to the wind direction at 10 m AGL, the CBL wind direction, the inversion-level wind direction, and the CBL shear direction. This is not surprising since there was very little directional shear observed within the CBL during CaPE.

show abstract

“…The spatiotemporal growth and decay of a precipitating system, determining its size and longevity, are governed by the background atmospheric parameters. These parameters include low-level wind convergence (Fankhauser et al 1985;Wilson et al 1992Wilson et al , 1998Kalthoff et al 2009), moisture variations at different levels (Crook 1996;Fabry 2006;Shige and Kummerow 2016;Chen et al 2017;Saikranthi et al 2018Saikranthi et al , 2019, stability, and vertical wind shear (Rotunno et al 1988;Wilson et al 1998;Chen et al 2015). Thus, to understand LSS and SSS's association with atmospheric background parameters, the diurnal variation of relative humidity (RH), vertical wind, and vertical shear of horizontal wind during nonrainy days and rainy days are computed from the ERA5 dataset.…”

Section: Background Atmospheric Parameters Associated With Lss and Sssmentioning

confidence: 99%

Diurnal Variation of Rainfall in the Presence of Large- and Small-Scale Precipitating Systems during Different Monsoon Seasons over a Complex Terrain (Gadanki) Region

Radhakrishna

Rao

2021

Journal of Applied Meteorology and Climatology

View full text Add to dashboard Cite

The diurnal cycle of rainfall by large-scale systems (LSS) and small-scale systems (SSS) has been studied over a complex terrain region (Gadanki) in southern peninsular India using eight years of data from a network of 36 rain gauges. The diurnal cycle of accumulated rainfall by LSS and SSS shows peaks at 22 LT and 19 LT, respectively, during the southwest monsoon (SWM) and 19 LT and ~17 LT during the northeast monsoon (NEM). Irrespective of the season and system size, the diurnal mode is the dominant mode of variation and explains ~60% (~43%) of variance during the SWM and ~54% (~36%) during the NEM in LSS (SSS) presence. The correlation structure of rainfall is anisotropic with an axis ratio of ~1.5 for LSS and ~1.4 for SSS. Propagating systems are prevalent (80 to 90% of times produce rain) in the presence of LSS during both seasons and play a dominant role in altering the diurnal cycle of rainfall over the Gadanki region. The conducive environment, like the presence of large RH, updrafts in lower- and mid-troposphere, and large lower- and small mid-tropospheric shears, favors convective initiation and propagation of precipitating systems during LSS in SWM and NEM. The atmosphere favors the convective initiation between 18 and 20 LT. The dry mid-troposphere and weak upward motion in the mid-troposphere inhibits mesoscale organization and forms SSS during the SWM. During the NEM, somewhat drier mid-troposphere than in LSS and small L-shear inhibits the convective organization and forms SSS between 15 and 18 LT.

show abstract

Objective Analysis of Constant Altitude Aircraft Measurements in Thunderstorm Inflow Regions

Cited by 10 publications

References 0 publications

Relationships between Large Precipitating Systems and Atmospheric Factors at a Grid Scale

Relationships between Large Precipitating Systems and Atmospheric Factors at a Grid Scale

Horizontal Convective Rolls: Determining the Environmental Conditions Supporting their Existence and Characteristics

Diurnal Variation of Rainfall in the Presence of Large- and Small-Scale Precipitating Systems during Different Monsoon Seasons over a Complex Terrain (Gadanki) Region

Contact Info

Product

Resources

About