emma6194/NO2-Analysis-Ghana-2025

Google Earth Engine script for monitoring NO₂ air pollution levels across Ghana (January 2025) # NO2-Analysis-Ghana-2025 Google Earth Engine script for monitoring NO₂ air pollution levels across Ghana (January 2025) Nitrogen Dioxide (NO₂) Trends over Ghana _A Google Earth Engine Script using Sentinel-5P TROPOMI Data_ Overview This project analyzes atmospheric Nitrogen Dioxide (NO₂) concentration over Ghana using the Sentinel-5P (TROPOMI) dataset. The script extracts NO₂ data, converts it to micromole units, generates a **time-series trend chart, and visualizes the spatial distribution for January 2025. Dataset - Source: COPERNICUS/S5P/OFFL/L3_NO2 - Sensor: Sentinel-5P (TROPOMI) - Variable: `NO2_column_number_density` - Temporal Coverage: January 1 – January 31, 2025 - Spatial Coverage: Ghana (using USDOS/LSIB_SIMPLE boundaries) Methods 1. Filter dataset by region (Ghana) and date (January 2025). 2. Convert units from mol/m² to micromole/m². 3. Generate time-series chart of mean NO₂ levels over Ghana. 4. Compute mean spatial distribution of NO₂ during the study period. 5. Visualize results using a custom color palette. Outputs - Time Series Chart: Daily mean NO₂ (micromole/m²) with linear trendline. - Map Visualization: Mean NO₂ concentration across Ghana for January 2025. Why This Matters Nitrogen Dioxide (NO₂) is a key air pollutant, mainly produced by fossil fuel combustion and industrial activities. Monitoring its trends helps in: - Assessing air quality - Identifying pollution hotspots - Supporting environmental policy and planning How to Use 1. Open Google Earth Engine Code Editor. 2. Copy and paste the script (`GEE_code`) into the editor. 3. Run the script to visualize results. License This project is released under the **MIT License**. You are free to use, modify, and distribute with attribution. --- ✍️ Author: Emmanuel Boateng 📅 Date: September 2025