Satellite-Derived Column Ozone Dataset over Alkaleri, Bauchi State (Nigeria) Generated Using Google Earth Engine from TOMS/MERGED and Sentinel-5P L3 O3 (2018–2025)

Title: Monthly mean total ozone column density over Alkaleri, Bauchi State, Nigeria (2018-2025) from Sentinel-5P TROPOMI

Description:

This dataset provides a curated monthly time series of total ozone column density over Alkaleri Local Government Area, Bauchi State, Nigeria, spanning January 2018 to December 2025. The data are derived from the Sentinel-5P TROPOMI (TROPOspheric Monitoring Instrument) Near-Real-Time (NRTI) Level-3 ozone product (COPERNICUS/S5P/NRTI/L3_O3), accessed and processed via the Google Earth Engine cloud platform.

The primary file (Alkaleri_S5P_Monthly_O3_2018_2025.csv) contains 96 monthly records with the following columns: system:time_start (date in milliseconds), year, month, and O3_column_number_density (mean ozone column density in mol/m²). A supplementary Excel file provides annual mean values for quick reference. The dataset also includes the complete Google Earth Engine JavaScript script used for data extraction and processing, ensuring full reproducibility.

Processing Methodology: Daily satellite imagery was filtered by the Alkaleri administrative boundary and aggregated to monthly mean composites using the ee.Reducer.mean() function at a 7000-meter scale. This workflow minimizes gaps from cloud cover and retrieval anomalies while providing a consistent time series suitable for trend analysis.

Potential Applications: This dataset is valuable for researchers studying regional atmospheric chemistry, ozone variability, UV radiation assessment, and climate impacts in West Africa. It addresses a critical data gap in a region with limited ground-based atmospheric monitoring infrastructure. The data can support model validation, environmental health studies, and baseline assessments for policy development.

Related Publication: This dataset supports the findings presented in the accompanying Data in Brief article "[Your Article Title]."

Keywords: Ozone, Sentinel-5P, TROPOMI, Nigeria, Alkaleri, Time Series, Remote Sensing, Atmospheric Data, Google Earth Engine.