Understanding Wildfires in 2023

Spatial Clustering using Satellite Imagery


Bogdan G. Popescu

1 Intro

In 2023, the world experienced a significant increases in the frequency of wildfires, posing unprecedented challenges to ecosystems, communities, and firefighting efforts. This memo aims to provide a comprehensive view of where the wildfires happened. The primary driver of of the surge in wildfires is the exacerbation of climate change. This memo aims to provide a comprehensive overview of wildfires that happened in 2023 and how scattered they are around the world.

2 Data

In order to map out the areas that have been affected by wildfires, I use data from The Terra and Aqua combined MCD64A1 Version 6.1 Burned Area data product, a monthly, global gridded 500m product containing per-pixel burned-area and quality information that I downloaded from Google Earth. The MCD64A1 burned-area mapping approach employs 500m MODIS Surface Reflectance imagery coupled with 1km MODIS active fire observations. The algorithm uses a burn sensitive vegetation index (VI) to create dynamic thresholds that are applied to the composite data. The VI is derived from MODIS shortwave infrared atmospherically corrected surface reflectance bands 5 and 7 with a measure of temporal texture. The algorithm identifies the date of burn for the 500m grid cells within each individual MODIS tile. The date is encoded in a single data layer as the ordinal day of the calendar year on which the burn occurred, with values assigned to unburned land pixels and additional special values reserved for missing data and water grid cells.

2.1 Maps for the Whole World

For brevity, I only include maps for January, July, August, and September 2023. Maps for every single month can be created upon request.

  • January, 2023