scispace - formally typeset
Search or ask a question
Topic

Convective available potential energy

About: Convective available potential energy is a research topic. Over the lifetime, 936 publications have been published within this topic receiving 43773 citations. The topic is also known as: CAPE.


Papers
More filters
Journal ArticleDOI
TL;DR: In this paper, the authors examined the precipitation efficiency and its relationship to physical factors by analyzing a two-dimensional cloud-resolving model simulation during TOGA COARE in order to investigate the relationship of precipitation efficiency to the physical factors, including convective available potential energy, water-vapor convergence, vertical wind shear, cloud ratio, sea surface temperature, air temperature, and precipitable water.
Abstract: The precipitation efficiency and its relationship to physical factors are examined by analyzing a two-dimensional cloud-resolving model simulation during TOGA COARE in this study. The basic physical factors include convective available potential energy, water—vapor convergence, vertical wind shear, cloud ratio, sea surface temperature, air temperature, and precipitable water. Precipitation efficiencies do not show a close relationship to air temperature nor to sea surface temperature nor to precipitable water. The precipitation efficiency increases as the water—vapor convergence rate increases and vertical wind shear weakens, whereas it decreases as the convective available potential energy dissipates and anvil clouds develop.

2 citations

Journal ArticleDOI
TL;DR: In this article , a seasonal correlation is found between the daily flash number and the extent of large CAPE values in the region of the Congo Basin depending on the season, and it also shows that the storms that occur within the regions of the main maximum of lightning activity, are more frequent and produce larger values of FRD.

2 citations

Journal ArticleDOI
TL;DR: In this article, three principle cases of conditions are indicated under which supplementary amounts of potential energy necessary to start a daughter convection in the cumulo-nimbus cloud can become available in the latter.
Abstract: Koschmieder's new thermodynamical theory of tornado formation (1940) makes it probable that a tornado (or a waterspout) develops when a warm air packet rises quickly within the convective mother cloud. In the present paper the three principle cases of conditions are indicated under which supplementary amounts of potential energy necessary to start a “daughter convection” in the cumulo-nimbus cloud can become available in the latter. Supply of moister air from below seems to be at least as important as that one of warmer air. However, the suddenness of the release of the said supplementary energy cannot be explained by the abrupt annihilation of an intercepting layer within the main body of the cumulo-nimbus, for the pre-existence of such a layer is incompatible with the general character of this type of cloud.

2 citations

Journal ArticleDOI
TL;DR: In this article, the authors derived the annual variation in planetary boundary layer (PBL) height from the profiles of conserved thermodynamic variables, i.e., virtual potential temperature θ v and equivalent potential temperature e, using radiosonde data at per-humid climate region, Ranchi (23°42′N, 85°33′E, 610 Âm asl) and semi-arid region, Anand (23Â35''N, 72°55′E
Abstract: The annual variation in planetary boundary layer (PBL) height is determined from the profiles of conserved thermodynamic variables, i.e., virtual potential temperature θ v and equivalent potential temperature θ e, using radiosonde data at per-humid climate region, Ranchi (23°42′N, 85°33′E, 610 m asl) and semi-arid region, Anand (23°35′N, 72°55′E, 45.1 m asl), India. Of all the variables, the θ v profile seems to provide the most reasonable estimate of the PBL height. This has been supplemented by T-Phi gram analysis for specific days. It has been found that in winter the height of boundary layer is very low due to subsidence and radiational cooling, while pre-monsoon months exhibit the most variable convection. It may be inferred that synoptic conditions accompanied by a variety of weather phenomena such as thunderstorms, onset and withdrawal of monsoons, etc. control the ABL over Ranchi, while daytime solar insolation and nighttime radiative cooling mainly control the ABL over Anand.

2 citations

Journal ArticleDOI
TL;DR: In this paper, the effects of convective adjustment time scale (τ) on the simulation of tropical climate were investigated, and it was found that there is a clear improvement in some of the key aspects of the simulated tropical climate with the revised convective adjusting time scale.
Abstract: This paper describes the effects of convective adjustment time scale (τ) on the simulation of tropical climate. The NCAR-Community Atmosphere Model version 3 (CAM3) has been used for this study. In the default configuration of the model, the prescribed value of τ, a characteristic time scale with which convective available potential energy (CAPE) is removed at an exponential rate by convection, is assumed to be 1 h. However, some recent observational findings suggest that, it is larger by around one order of magnitude. In order to investigate the dependence of tropical climate simulation to this time scale, we conducted two simulations, one with a time scale of 1 h (CTRL) and another with 8 h (EXPT), and examined the differences in simulated climate. For this, we analyzed both the mean as well as transient features, viz., seasonal mean quantities, equatorial waves, and meridional migration of convective disturbances. The spatial distributions of seasonal mean precipitation are found to be better in EXPT. The spatial correlation coefficients of CTRL and EXPT with the observations are 0.79 and 0.83, respectively, for northern hemisphere winter. Similarly, for northern hemisphere summer, the values are 0.67 and 0.79, respectively. In addition, there is also an improvement in the simulation of equatorial waves, specifically, the Kelvin waves, Madden–Julian oscillation, and n = 1 equatorial Rossby waves become more realistic in EXPT. The characteristics of meridional migration of convective activity over tropics also become more reasonable in EXPT. Thus, it is found that there is a clear improvement in some of the key aspects of the simulated tropical climate with the revised convective adjustment time scale.

2 citations


Network Information
Related Topics (5)
Climate model
22.2K papers, 1.1M citations
89% related
Stratosphere
15.7K papers, 586.6K citations
86% related
Monsoon
16K papers, 599.8K citations
85% related
Sea surface temperature
21.2K papers, 874.7K citations
84% related
Precipitation
32.8K papers, 990.4K citations
84% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
202365
202291
202151
202038
201932
201827