link:

https://www.researchgate.net/publication/329522594_Spatiotemporal_monitoring_of_Methane_over_Iraq_during_2003-2015_retrieved_from_Atmospheric_Infrared_Sounder_AIRS

Abstract:

Observations of methane (CH4) retrieved from Atmospheric Infrared Sounder (AIRS) on the EOS/Aqua platform from 2003-2015 show a strong, plume-like enhancement of CH4 over central and southern-east parts of Iraq during August – September, with the maximum occurring in early September and minimum in March – May over western, southwest, and north-east regions. The percentage change differences results shows the highest differences occurred over the central and southern regions and the smallest differences occurred over the western and southwest regions. To better validate the retrieved data from AIRS three stations at different locations were chosen for trend analysis. The mean and standard deviation in Mosul, Baghdad and Basrah was (3.610 ± 0.042, 3.818 ± 0.048, 3.824 ± 0.055) x10 19 Mole.Cm -2 respectively for monthly long term trend analysis. Annual trend analysis shows positive trends, and ranged between (0.0083 and 0.0097) Mole.Cm -2 .y -1 for Mosul and Basrah, respectively. Monthly trend analysis have positive trends (0.0092) Mole.Cm -2 .y -1 for Mosul and (0.0107) Mole.Cm -2 .y -1 for Baghdad and Basrah. The annual linear growth rate were (2%) for Mosul, and (3%) for Baghdad and Basrah, and monthly linear growth rates were (5%) for Mosul and Baghdad, and (6%) for Basrah. Further daily long term trend shows significant linear increase of (3.7 %) caused a trend of (0.0107 × 10 19 ) Mole.Cm -2 .y -1 in Baghdad. The standard deviation of variation in daily average CH4 as a percentage deviation from the mean for the departure from the mean was (1.62%), (0.06×10 19 Mole.Cm -2 ). And the day to day variation with a clear seasonal change shows standard deviation of enter sequential changes was (0.053 × 10 19 ) Mole.Cm -2 . These results indicate that Satellite observations efficiently show the temporal variations of the CH4 values over different regions.