Analysis of Trend and Temporal Variability of Carbon Monoxide (CO) Concentrations in Basra City for the Period 1991–2024

Abstract

dangerous air pollutants in Basra Governorate due to its direct association with oil-related activities, flaring processes, and the increasing density of transportation. This study aims to analyze the spatial and temporal variability of CO concentrations over three time periods extending from 1991 to 2024.

The research adopts a quantitative analytical approach using statistical methods to extract the temporal trend coefficient, as well as to calculate total and relative changes. The results indicate a clear temporal variation in CO concentrations at the Basra station across months and study periods. Positive trends prevailed in most months, particularly during the third period (2014–2024), which recorded the highest values of relative and total change, reflecting a more pronounced increase in recent years.

In contrast, temporary negative trends were observed during the second period (2003–2013), indicating a partial decline in concentrations. Despite these fluctuations, the overall trend throughout the study period is characterized by weakness or near stability, suggesting relative consistency in CO concentration levels.

The highest values were concentrated in certain months, especially April, while all recorded concentrations remained within the permissible environmental and health standards both locally and internationally. In general, the results reflect that recent changes are seasonal in nature and are linked to human activities and climatic conditions, without a fundamental long-term shift in gas levels. The observed variations in change values are attributed to the concentration of industrial facilities and major transportation routes.