The atmospheric ozone is an important trace gas for ecosystem,climate and environment.Ozone is mainly located in the stratosphere approximately ranging from 10 to 50 kilometers above the Earth surface,with maximum value between 10 and 30 kilometers.Ozone layer heats up the stratosphere by absorbing solar ultraviolet radiation.The decrease in ozone concentration can cause decrease in the temperatures of upper-stratosphere and increase in the temperatures of upper-troposphere and lower-stratosphere(UTLS).Therefore,the existence of ozone layer is important to maintain the vertical structure and radiation balance of the atmosphere.Estimation showed that land surface temperatures could be 1-2 degrees higher if not for ozone absorbing parts of the solar energy.Ozone plays an important role in the dynamics,thermodynamics,radiation and atmospheric chemistry of the troposphere and stratosphere,and therefore is vital for atmospheric circulation and climate,as the tropopause existence and temperature structure largely determined by the total ozone in the stratosphere.Total column ozone,defined as total amount of ozone in a column of air from the surface to the top of the atmosphere,is a satellite product retrieved at ultraviolet wavelength.The ozone dataset spans from 1979 to 2014 with a spatial resolution of 1°latitude by 1.25°longitude.The satellites used include NIMBUS-7/TOMS(1979-1993),Meteor-3/TOMS(1994),EP/TOMS(1997-2005),NOAA/SBUV-2,AURA/OMI and FY-3A/B/TOU.Global and regional distribution and variation of total column ozone have been studied based on the total column ozone(TCO)data during 1979 and 2014 from different spaceborne instruments including TOMS(total ozone mapping spectrometer)series,OMI(ozone monitoring instrument)and TOU(total ozone unit)series.The distribution and variation of total column ozone over globe and some key regions are studied.The TCO differences of distribution and variation(DAV)between the Northern and Southern Hemisphere are discussed and possible impact factors on TCO DAV are considered.Special attention has been focused on the ozone variation for China,Tibetan Plateau and Polar regions.The monitoring of Antarctic ozone hole and Arctic ozone is also conducted using FY3 satellite data.The results showed that TCO DAV are very nonuniform in the middle and high latitudes and polar regions.The ozone loss over polar regions continues to exist.For Tibetan Plateau,the TCO variation is larger than the other regions of the same latitude.The mechanism of ozone variation over Tibetan Plateau is complicated.