The Application Of Energy Structural Analysis In Diagnosing Thunder Wind

This paper analysed two typical thunderstorm gale weather which occurred in hubei province from the Angle of the conventional weather analysis and atmospheric energy (the one occurred in july27,2007.we wii call it "727" thunderstorm gale weather for short;the other occurrde in june3,2008. we wii call it "603" thunderstorm gale weather for short). in the paper we using several kind data such as NCEP reanalysis data, conventional observation data and doppler weather radar data. It was revealed that:1. the atmosphere energy can show the motion of the air effectively. Increasing of atmosphere energy can be the index of the disaster weather coming up, on the contrary, decreasing of atmosphere can be the index of disappearing of convection. So the energy of atmosphere can used to forecast severe convection ahead of time. the concept of energy potential vorticity proposed in this paper combines energy synoptic meteorology with equation of motion. It explains the movement of atmosphere energy in nature. When use it to analyze the case, we can see that it is useful. For thunder wind, it is the omen when the thunder wind will occur that there is high dry energy potential vorticity on the upper air and the dry energy potential coming down. The unstable region of lower layer combine with baroclinic system will be the area where the thunder wind break out.2. there will be many background of weather which could influence disastrous weather, different kinds of synoptic situation may produce varying degrees disastous weather. Thunder wind usally occurs in summer and we will find similarity after contrasting the thunder wind occcured in different synoptic situations, that is:the invasion of weak cold air on upper air increases burstiness of convection, produces disaster weather in short time. The high wind speed in can keep the disaster weather more suffering of gale.3. doppler weather radar is one of the most effective tool which is used in observing summer severe convection. For the thunder wind, its doppler effect is obvious, especially in doppler velocity. The thunder wind could be take place when the strong wind area show in doppler radar coming down; adverse wind area is an important information for the thunder wind, it shows the serever convection is grown when we can see the adverse wind area on radar, the thunder wind may be occurred when it is disappearing.4. V-3θ energy structural analysis is an useful tool for weather analysis. It can show the evolution of local atmosphere energy. Unstable energy and the evolution of vapour vertical distribution can announce the evolution of weather. Ultralow temperature can be the foreboding information for convection.