Total Ozone Column Trends over Five Iraqi Selected Provinces Using TOMS Data

Abstract

Monthly and annual values of the total column ozone(TOC) amount have been analyzed for five stations of Iraq for the period from 1979 to 2012 employing Total ozone Mapping Spectrometer (TOMS) data point, It is found that ozone variation is function of latitude, where the higher values of total ozone column occurs at the northern station which represented by Mosul station, it decreases gradually from northern station (Mosul) passing by middle region stations (Biji, Baghdad and Rutba) to southern station (Basra). The values of Total ozone column start to increase gradually from November to reach its maximum at March then it decreases gradually to reach its minimum values at October. The analysis of the spatial distribution of the monthly average of total ozone column for each month of the year has been made. It is found that the largest of total ozone column amounts occurs systematically over the northern regions during winter whereas in spring and early summer months the maximum values of total ozone column directed to the northwestern regions of the country, The overall period (1979-2012) Trend Analysis presented negative trends for all months in five considered stations except Baghdad station during July and August gives a strong positive trend which refer to a notable enhancement of TOC which reaches to (0.443) DU/Year, Whereas the first period (1979-1992) showed a clear negative trend for all months also for all stations except Baghdad station which presented a weak positive trend during late autumn station, the second period (1997-2012) trends analysis presented negative trends for all months in five considered station except Baghdad station during all months gives a strong positive trend. Finally the results of the second period trend analysis indicated that the ozone layer may be responding as expected to the reducing on ozone-depleting substances imposed by the Montreal Protocol.