Study of the Behavior of Air Parcels, using PIXE, Hysplit and Wind Rose in the Metropolitan Zone of Toluca Valley, Mexico

Aim: The objective of this work was to determine the behavior of the trajectories of the air plots in two sites (San Mateo Atenco-(SM) and San Lorenzo Tepaltitlán-(SL)), in the atmosphere of the Metropolitan Zone of the Toluca Valley (MZTV).

Methodology: In the atmosphere of the MZTV, using HYSPLIT a Backward trajectory direction analysis was performed from June 29 to July 8, 2021, considering for each day the summertime schedules of the center, indicating its Coordinated Universal Time (UTC). An ANOVA analysis (with a significance level of α=0.05) was performed for the concentrations of SM and SL obtained with PIXE, with the objective of seeing the equality of their behavior.

Results: The behavior of the direction of the trajectories of the air plots in both sites is similar and the trajectories for the same day are the same in both sites but different on another day; It was determined that during night-day (19 to 12 h of the following day) the behavior is similar and changes during the remaining time, being variable. In general, the origin of the trajectories of the air plots for both sites of the MZTV is predominantly from the southeast, a situation that was confirmed with Wind Roses. Of the ANOVA analysis, the p-value was in all cases greater than the significance level of 0.05, the null hypothesis was accept, and it is possible to conclude that the elemental chemical composition of PM2.5 have equal means in both sites.

Conclusion: Among other, it is possible to consider the behavior of meteorological parameters and thus take them into account for sampling studies of criteria pollutants such as PM2.5.`