African burned area and fire carbon emissions are strongly impacted by small fires undetected by coarse resolution satellite data - PubMed Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2021 Mar 2;118(9):e2011160118.
doi: 10.1073/pnas.2011160118.

African burned area and fire carbon emissions are strongly impacted by small fires undetected by coarse resolution satellite data

Ruben Ramo  1   2 , Ekhi Roteta  3 , Ioannis Bistinas  4   5 , Dave van Wees  4 , Aitor Bastarrika  3 , Emilio Chuvieco  2 , Guido R van der Werf  4
Affiliations

African burned area and fire carbon emissions are strongly impacted by small fires undetected by coarse resolution satellite data

Ruben Ramo et al. Proc Natl Acad Sci U S A. .

Abstract

Fires are a major contributor to atmospheric budgets of greenhouse gases and aerosols, affect soils and vegetation properties, and are a key driver of land use change. Since the 1990s, global burned area (BA) estimates based on satellite observations have provided critical insights into patterns and trends of fire occurrence. However, these global BA products are based on coarse spatial-resolution sensors, which are unsuitable for detecting small fires that burn only a fraction of a satellite pixel. We estimated the relevance of those small fires by comparing a BA product generated from Sentinel-2 MSI (Multispectral Instrument) images (20-m spatial resolution) with a widely used global BA product based on Moderate Resolution Imaging Spectroradiometer (MODIS) images (500 m) focusing on sub-Saharan Africa. For the year 2016, we detected 80% more BA with Sentinel-2 images than with the MODIS product. This difference was predominately related to small fires: we observed that 2.02 Mkm2 (out of a total of 4.89 Mkm2) was burned by fires smaller than 100 ha, whereas the MODIS product only detected 0.13 million km2 BA in that fire-size class. This increase in BA subsequently resulted in increased estimates of fire emissions; we computed 31 to 101% more fire carbon emissions than current estimates based on MODIS products. We conclude that small fires are a critical driver of BA in sub-Saharan Africa and that including those small fires in emission estimates raises the contribution of biomass burning to global burdens of (greenhouse) gases and aerosols.

Keywords: Africa; MODIS; Sentinel 2; carbon emissions; small fires.

PubMed Disclaimer

Conflict of interest statement

The authors declare no competing interest.

Figures

Fig. 1.
Fig. 1.
Area burned in 2016, expressed as the fraction of each 0.25° grid cell according to FireCCISFD11 (A), GFED4s (B), and the difference of fractions between them (FireCCISFD11-GFED4s) (C). The rectangular blank grids in A correspond to S2 scenes where no active fires were detected by MODIS sensors in 2016. Therefore, no BA was mapped in those tiles.
Fig. 2.
Fig. 2.
Fraction of total BA stemming from fires smaller than 100 ha (plotted on a 0.05° grid) detected by the FireCCISFD11 product. The rectangular blank tiles correspond to MSI scenes where no active fires were detected and therefore do not include any BA.
Fig. 3.
Fig. 3.
Monthly BA estimates for FireCCISFD11, MCD64A1, and GFED4s for Northern Hemisphere (A) and Southern Hemisphere (B) Africa. The red line shows the proportion of fires <100 ha to total BA for the FireCCISFD11 product.
Fig. 4.
Fig. 4.
Monthly carbon emission estimates based on FireCCISFD11 and MCD64A1 BA using the 500-m model by Van Wees et al. (28) and emissions from GFED4s (0.25°) for Northern Hemisphere (A) and Southern Hemisphere (B) Africa.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Kloster S., Lasslop G., Historical and future fire occurrence (1850 to 2100) simulated in CMIP5 Earth System Models. Global Planet. Change 150, 58–69 (2017).
    1. Bowman D. M., et al. ., Human exposure and sensitivity to globally extreme wildfire events. Nat. Ecol. Evol. 1, 0058 (2017). - PubMed
    1. Roos C. I., et al. ., Living on a flammable planet: Interdisciplinary, cross-scalar and varied cultural lessons, prospects and challenges. Philos. Trans. R Soc. Lond. B Biol. Sci. 371, 20150469 (2016). - PMC - PubMed
    1. Benali A., et al. ., Bimodal fire regimes unveil a global‐scale anthropogenic fingerprint. Glob. Ecol. Biogeogr. 26, 799–811 (2017).
    1. Morton D., et al. ., Agricultural intensification increases deforestation fire activity in Amazonia. Glob. Change Biol. 14, 2262–2275 (2008).

Publication types

LinkOut - more resources