The Available Potential Energy in Study of Various Scales Atmospheric Circulations

English Abstract:

In general all atmospheric perturbation contains kinetic and potential components of energy responsible for their maintenance. The application of available potential energy (APE) in study of synoptic and mesoscale meteorology objects are examined here. Developing of suitable approach for APE resources estimation within specified above range of scales is the main research purpose, and then practical evaluation of thus obtained results.

The proposed method oriented to regular data from atmospheric modeling, takes into account possible effect of latent heat release. In principle it combines APE approach introduced by Lorenz E.N. (1955) and convection characteristic known as CAPE. Computationally method based on spatial filter which allows separating various scale of process (from synoptic to meso-γ). In results it brings spatial distribution of APE resources, significant for certain scale of circulation. Experiments with changing filter threshold indicate spatial scales of convection and synoptic front energy resources overlap in range of 350-600 km. That describes convective contribution in general front instability. In range of 1000-2000 km overlap energy resources of fronts and air mass responsible for cyclone development are observed.

Comparative testing of frontal-scale APE, CAPE and convective precipitation into NCEP GFS-0.5 model made for thunderstorms location forecast over South-East Europe during warm half 2013. Data from World Wide Lightning Location Network (http://wwlln.net) used as check source of thunderstorms location. In general, statistical characteristics show quite similar forecast accuracy for all parameters.

Another useful features are demonstrated by APE fields is visual representation of evolution tendency, appearance and disappearance of cyclones, mesocyclones, atmospheric fronts, convective systems and isolated convection, some local orographic phenomena. Total quantitative estimates may be used for comparison of process intensity, including solving quality control problem in atmospheric simulation, and also as mode of climate changes interpretation. Some examples of such application are given in the presentation.