The air quality in the Guadalajara metropolitan area has worsened during 2023, with only 134 days of “good air quality” registered between January 1 and November 30, according to the state government’s air monitoring network (Mide).
The data represents a 175-percent increase over the 2022 figures, according to Jalisco’s Department of the Environment and Territorial Development (Semadet)
When the Guadalajara metropolitan area’s Imeca index exceeds the 100-point threshold in any of the system’s 11 zones, the air quality in that area is considered “Mal” (Bad). From 151 to 200, it is deemed “May Mal” (Very Bad”) and from 201 up “Extremamente Mal” (Extremely Bad).
A “pre-contingency” alert is issued after levels exceed 120 Imecas, followed by a phase one alert at 151 Imecas, a phase two alert at 201 Imecas and a phase three alert at 251 Imecas. Local governments put into place pollution reduction measures at each level of the contingency, and the public is advised to take certain steps to cutback their activities. Alerts are stood down when air quality levels have returned to “normal” for two hours.
According to Semadet, state authorities declared 51 pre-contingencies in the Guadalajara metropolitan area through December 2023, and four phase-one alerts. Only 20 pre-contingencies were issued in 2022.
The first phase one pre-contingences of 2024 were registered January 2 and 3, when the Imeca scale went above 120 points in the southern Guadalajara area of Las Pintas.