In 2023, wildfires around the world released 7,330 million tonnes of CO2, as reported by the EU’s Copernicus Atmosphere Monitoring Service (CAMS). This amount is notably higher than the 6,000 million tonnes of greenhouse gases (CO2 and others) emitted by the United States in 2022.
Wildfire Emissions in 2023
- CO2 Release: Wildfires released 7,330 million tonnes of CO2 globally in 2023.
- Comparison: This emission is higher than the 6,000 million tonnes of CO2 emitted by the US in 2022.
Early Wildfires in 2024
- Countries Affected: By mid-May 2024, wildfires hit 11 countries, notably Canada.
- Canadian Fires: Fires began in early May, releasing 55 million tonnes of CO2 by mid-May.
2024 Wildfire Forecast
- Increased Risk: North American agencies warn of heightened wildfire risk due to warm, dry, and windy conditions.
Challenges in Emissions Measurement
- Complex Calculations: Emissions are hard to measure due to unpredictable factors like temperature, wind, and humidity.
- Global Warming Impact: Rising global temperatures over the last four decades have increased wildfire frequency and intensity.
Fires in New Areas
- Higher Elevations: Wildfires are reaching higher elevations in the western US, previously less susceptible.
- Recovery Time: Increased frequency and intensity of fires reduce forests’ recovery time, leading to more CO2 in the atmosphere.
Measuring Wildfire Emissions
- IPCC Guidelines: Emissions are calculated using burned area, biomass density, emission factor, and combustion factor.
- Different Methods: The EU’s CAMS uses fire radiative power measured from satellite data for its calculations.
Uncertainties in Measurement
- Fire Detection Issues: Satellite data accuracy can be affected by weather conditions like cloud cover.
- Tool Limitations: Tools like MODIS may miss small fires, leading to conservative emission estimates.
Conservative Estimates
- Underestimation: Many small fires are undetected, leading to conservative emission estimates.
- Study Findings: Sentinel-2 satellite images revealed significantly more burned land than MODIS, indicating higher CO2 emissions.
Smouldering Fires
- Detection Challenges: Smouldering fires, common in peatlands, are hard to detect and emit large amounts of carbon.
Emission Factors
- Regional Data: Most emission factor data come from the US and Europe, affecting accuracy in other regions.
- Sampling Methods: Emission factors are derived from lab or field experiments, often with regional variability.
India’s Approach
- Current Contribution: India’s forest fires contribute 1-1.5% to global wildfire emissions.
- Climate Threat: Climate change could increase wildfire emissions in fire-prone regions like Himachal Pradesh and Uttarakhand.
Inconsistent Estimates
- Variability: Emission inventories can vary significantly, with some datasets showing differences by a factor of two or three.
- Study Example: A 2015 study showed notable differences in CO2 emissions reported by various datasets.
Regional Differences
- Variations: Significant regional differences exist in emissions estimates across different inventories.
- Higher Emissions: The Fire Inventory (FINN) reports higher emissions in South America and Southeast Asia than other sources.
BBURNED Initiative
- Community Effort: Launched in December 2022 to better quantify uncertainties in biomass burning emission estimates.
- Workshops: Focuses on emissions inventories, methodologies, and improving collaboration and data sharing.
Future Improvements
- Better Models: Improved estimates will enhance models and simulations, aiding in understanding wildfire impacts on health and climate.
Source: Wild guess
Key Terms Explained
BBURNED Initiative
BBURNED stands for Biomass Burning Uncertainty: ReactioNs, Emissions and Dynamics. It’s an international scientific effort focused on improving our understanding of uncertainties in emissions from biomass burning (wildfires, prescribed burns, agricultural fires). It aims to better represent the impact of these fires on atmospheric chemistry and public health.
Global Fire Emissions Database (GFED)
GFED is a freely available resource providing estimates of global fire emissions and burned areas. It uses satellite data to calculate monthly burned area, emissions from different fire types, and trace gas/aerosol emissions. This data is crucial for studying the impact of fires on climate, air quality, and ecosystems.
Moderate Resolution Imaging Spectroradiometer (MODIS)
MODIS is a sensor instrument onboard NASA’s Terra and Aqua satellites. It collects high-resolution data on Earth’s surface, atmosphere, and oceans. Data from MODIS is used in various applications, including fire detection, land cover mapping, and studying ocean productivity. The GFED initiative utilizes MODIS data for burned area estimates.
Global Fire Assimilation System (GFAS)
GFAS is a near-real-time system that retrieves fire radiative power (FRP) from satellites and assimilates it into atmospheric models. This allows for continuous monitoring of global fire activity and its impact on air quality forecasts.
Fire Radiative Power (FRP)
FRP is a measure of the radiant energy emitted by a fire. It is derived from satellite observations and provides an indication of fire intensity. GFAS relies on FRP data for its fire monitoring activities.
Copernicus Atmosphere Monitoring Service (CAMS)
CAMS is an operational service implemented by the European Centre for Medium-Range Weather Forecasts (ECMWF) on behalf of the European Union. It provides continuous monitoring and information on atmospheric composition. GFAS, the Global Fire Assimilation System, is one of the services offered by CAMS.