Climatic And Anomalous Analysis Of Atmospheric Angular Momentum Balance

With the wind, pressure and sea surface temperature (SST) data provided by NCEP/NCAR reanalysis project and excess length of day (LOD) data provided by International Earth Rotation Service (IERS), atmospheric angular momentum (AAM) and its horizontal and vertical transportation are computed and analyzed, which are in accordance with maintenance of the zonal circulation. And the anomalous AAM is highly consistent with El Nino events. Frictional torque and mountain torque are of the same order and show similar seasonal variation, but the latter shows more complex spacial distribution. Correlation analysis is made and good positive correlation is found between AAM and SST of Nino III section. Positive correlation is also found between AAM and mountain torque, while negative correlation between AAM and friction torque. Cross spectrum analysis is made between AAM, torque, SST and LOD. It is found that significant correlations exist between those series on time scales of shorter than one year. And intimate link is found between significant correlation periods longer than one year and El Nino period.The above work gives a quite complete and systematic analysis of the AAM balance in a long time, including climatic and anomalous characteristics, and links the AAM and its transportation, earth-atmosphere angular momentum exchange (mountain torque and friction torque) with LOD and SST. The intimate link is confirmed between AAM and LOD, El Nino.