Theoretical Studies And Diagnostic Analyses Of Perturbation Potential Energy

Atmospheric energetics is an important section of atmospheric science researches all along, and especially, atmospheric energy variation may be used to link heating source (sink) change in atmosphere and atmospheric circulation anomalies. In order to extend energy efficiency investigations from global atmospheric average to local or regional scale, a new concept on perturbation potential energy (denoted as LPPE, also PPE for short) is proposed in the present paper, so as to examine transform each other between atmospheric potential energy and kinetic energy. Based on the PPE, some properties of atmospheric reference state (ARS) are theoretically studied and diagnostic analyses for related problems of local or regional energetics are carried out by using reanalysis data. Furthermore, surface PPE is studied from theoretical document to actual estimation and some valuable results are obtained. The major results and conclusions of this study may be summarized as follow:1) Some important characteristics of the atmosphere during the process of adiabatic adjustment, including the invariability of atmospheric entropy range and local surface potential temperature, and the conservation of the atmospheric mass intervened between isentropic surfaces and ground when isentropic surfaces intersect with ground, are documented. The analysis showed that, the ARS for investigation on available potential energy should be defined objectively as the state which could be approached from the existing atmosphere by adiabatic adjustment, and be related to the atmospheric state before adjustment, and ARS is different corresponding to the existing atmosphere state at different time.2) The new concept on LPPE is put forward and its mathematical expression including the first-order moment of PPE (FOM-PPE), the second-order moment of PPE (SOM-PPE), and surface PPE are derived. The SOM-PPE averaged all over the globe just is equal to traditional available potential energy, and the latter is the special case of PPE in global mean sense. In brief, the SOM term is most in the PPE averaged all over the globe, whereas the FOM-PPE is most in regional and local scale.3) The energy budget equations of local atmospheric kinetic energy (AKE) and FOM-PPE are derived respectively. In local situation, provided that adiabatic and frictionless condition, the...