@article{fdi:010089537,
  title = {{H}igh-resolution data reveal a surge of biomass loss from temperate and {A}tlantic pine forests, contextualizing the 2022 fire season distinctiveness in {F}rance},
  author = {{V}allet, {L}. and {S}chwartz, {M}. and {C}iais, {P}. and van {W}ees, {D}. and de {T}ruchis, {A}. and {M}ouillot, {F}lorent},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he frequency and intensity of summer droughts and heat waves in {W}estern {E}urope have been increasing, raising concerns about the emergence of fire hazard in less fire-prone areas. {T}his exposure of old-growth forests hosting unadapted tree species may cause disproportionately large biomass losses compared to those observed in frequently burned {M}editerranean ecosystems. {T}herefore, analyzing fire seasons from the perspective of exposed burned areas alone is insufficient; we must also consider impacts on biomass loss. {I}n this study, we focus on the exceptional 2022 summer fire season in {F}rance and use very high-resolution (10 m) satellite data to calculate the burned area, tree height at the national level, and subsequent ecological impact based on biomass loss during fires. {O}ur high-resolution semi-automated detection estimated 42 520 ha of burned area, compared to the 66 393 ha estimated by the {E}uropean automated remote sensing detection system ({EFFIS}), including 48 330 ha actually occurring in forests. {W}e show that {M}editerranean forests had a lower biomass loss than in previous years, whereas there was a drastic increase in burned area and biomass loss over the {A}tlantic pine forests and temperate forests. {H}igh biomass losses in the {A}tlantic pine forests were driven by the large burned area (28 600 ha in 2022 vs. 494 hayr-1 in 2006-2021 period) but mitigated by a low exposed tree biomass mostly located on intensive management areas. {C}onversely, biomass loss in temperate forests was abnormally high due to both a 15-fold increase in burned area compared to previous years (3300 ha in 2022 vs. 216 ha in the 2006-2021 period) and a high tree biomass of the forests which burned. {O}verall, the biomass loss (i.e., wood biomass dry weight) was 0.25 {M}t in {M}editerranean forests and shrublands, 1.74 {M}t in the {A}tlantic pine forest, and 0.57 {M}t in temperate forests, amounting to a total loss of 2.553 {M}t, equivalent to a 17 % increase of the average natural mortality of all {F}rench forests, as reported by the national inventory. {A} comparison of biomass loss between our estimates and global biomass/burned areas data indicates that higher resolution improves the identification of small fire patches, reduces the commission errors with a more accurate delineation of the perimeter of each fire, and increases the biomass affected. {T}his study paves the way for the development of low-latency, high-accuracy assessment of biomass losses and fire patch contours to deliver a more informative impact-based characterization of each fire year.},
  keywords = {{FRANCE} ; {EUROPE} ; {ZONE} {TEMPEREE}},
  booktitle = {},
  journal = {{B}iogeosciences},
  volume = {20},
  numero = {18},
  pages = {3803--3825},
  ISSN = {1726-4170},
  year = {2023},
  DOI = {10.5194/bg-20-3803-2023},
  URL = {https://www.documentation.ird.fr/hor/fdi:010089537},
}