Dust concentration and meteorological background

The Green Sentinel senors reported a significant increase in PM10 and PM2.5 particulate matter concentrations on 11 June 2025 between 02:00 and 04:00 am, due to adverse meteorological effects.

The calm period and the decrease of the mixing layer thickness increased the local dust concentrations. However, a slow decrease in dust concentration was observed due to dilution with increasing airflow and mixing.

A similar phenomenon can be observed from the data of the independent Kalotaszeg Square station of the National Air Pollution Monitoring Network.

A smaller but similar phenomenon was observed on 9 June between 02 and 04 am.

Compiled by the Green Sentinel Air Working Group:

• Prof. Dr. Sándor Kéki - Deputy Head, Co-Chair of the Air Working Group
• Dr. Zsófia Kertész - member of the Air Working Group
• István Lázár - member of the Air Working Group