Air Quality Data from Regulatory AQMS and Low-Cost Sensors in Molí del Sol, Valencia (May 31 2024 - January 23, 2025)

This dataset contains parallel time-series data for air quality and meteorological parameters, collected for the purpose of calibrating low-cost air quality sensors (LCS) against a regulatory-grade reference monitoring station. The data was collected continuously for 238 days, from May 31, 2024, to January 23, 2025, at the Moli del Sol air quality station in the Valencian Community, Spain. The dataset is divided into two main sources: Reference Data (GVA): The gva_*.csv files originate from an official Valencian AQ Monitoring Network (VAQMN) station, managed by the Generalitat Valenciana (GVA). This data represents the high-accuracy "ground truth" measurements from professional, regulatory-grade instruments. The selected reference station is 'Moli del Sol'. The selected reference station is located at (lat: 39.48113875, lon: -0.40855865), and is identified by its code 46250048 Low-Cost Sensor Data (LCS): The n1_*.csv and n2_*.csv files contain raw data collected by two IoT nodes (Node 1 and Node 2) equipped with ZPHS01B multi-sensor modules. These nodes were co-located with the official GVA station to ensure measurements were taken under identical ambient conditions. The raw sensor data from all sources has been processed and aggregated into synchronized time intervals of 10, 30, and 60 minutes to facilitate direct comparison and the training of machine learning models. This dataset is designed for developing and evaluating machine learning algorithms to improve the accuracy of raw pollutant readings (e.g., Ozone, Nitrogen Dioxide) from the low-cost sensors, a process detailed in the associated research publication.