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Landscape fires show large variability in the amount of biomass or fuel consumed per unit area burned. Fuel consumption (FC) depends on the biomass available to burn and the fraction of the biomass that is actually combusted, and can be combined with estimates of area burned to assess emissions. While burned area can be detected from space and estimates are becoming more reliable due to improved algorithms and sensors, FC is usually modeled or taken selectively from the literature. We compiled the peer-reviewed literature on FC for various biomes and fuel categories to understand FC and its variability better, and to provide a database that can be used to constrain biogeochemical models with fire modules. We compiled in total 77 studies covering 11 biomes including savanna (15 studies, average FC of 4.6 t DM (dry matter) ha−1 with a standard deviation of 2.2), tropical forest (n = 19, FC = 126 ± 77), temperate forest (n = 12, FC = 58 ± 72), boreal forest (n = 16, FC = 35 ± 24), pasture (n = 4, FC = 28 ± 9.3), shifting cultivation (n = 2, FC = 23, with a range of 4.0–43), crop residue (n = 4, FC = 6.5 ± 9.0), chaparral (n = 3, FC = 27 ± 19), tropical peatland (n = 4, FC = 314 ± 196), boreal peatland (n = 2, FC = 42 [42–43]), and tundra (n = 1, FC = 40). Within biomes the regional variability in the number of measurements was sometimes large, with e.g. only three measurement locations in boreal Russia and 35 sites in North America. Substantial regional differences in FC were found within the defined biomes: for example, FC of temperate pine forests in the USA was 37% lower than Australian forests dominated by eucalypt trees. Besides showing the differences between biomes, FC estimates were also grouped into different fuel classes. Our results highlight the large variability in FC, not only between biomes but also within biomes and fuel classes. This implies that substantial uncertainties are associated with using biome-averaged values to represent FC for whole biomes. Comparing the compiled FC values with co-located Global Fire Emissions Database version 3 (GFED3) FC indicates that modeling studies that aim to represent variability in FC also within biomes, still require improvements as they have difficulty in representing the dynamics governing FC.

Instantaneous estimates of the power released by fire (fire radiative power, FRP) are available with satellite active fire detection products. The temporal integral of FRP provides an estimate of the fire radiative energy (FRE) that is related linearly to the amount of biomass burned needed by the atmospheric emissions modeling community. The FRE, however, is sensitive to satellite temporal and spatial FRP undersampling due to infrequent satellite overpasses, cloud and smoke obscuration, and failure to detect cool and/or small fires. Satellite FRPs derived over individual burned areas and fires have been observed to exhibit power law distributions. This property is exploited to develop a new way to derive FRE, as the product of the fire duration and the expected FRP value derived from the FRP power law probability distribution function. The method is demonstrated and validated by the use of FRP data measured with a dual‐band radiometer over prescribed fires in the United States and by the use of FRP data retrieved from moderate resolution imaging spectroradiometer (MODIS) active‐fire detections over Brazilian deforestation and Australian savanna fires. The biomass burned derived using the conventional FRP temporal integration and power law FRE estimation methods is compared with biomass burned measurements (prescribed fires) and available fuel load information reported in the literature (Australian and Brazilian fires). The results indicate that the FRE power law derivation method may provide more reliable burned biomass estimates under sparse satellite FRP sampling conditions and correct for satellite active‐fire detection omission errors if the FRP power law distribution parameters and the fire duration are known. Key Points Biomass burned retrieved conventionally from FRP significantly sensitive to sampling New method based on observed FRP power law properties solves this sensitivity New method demonstrated with ground and satellite fire observations

ObjectiveThe impact of a screening programme on colorectal cancer (CRC) incidence in its target population depends on several variables, including coverage with invitations, participation rate, positivity rate of the screening test, compliance with an invitation to second-level assessment and endoscopists’ sensitivity. We propose a synthetic indicator that may account for all the variables influencing the potential impact of a screening programme on CRC incidence.DesignWe defined the ‘rate of advanced adenoma on the target population’ (AA-TAP) as the rate of patients who received a diagnosis of advanced adenoma within a screening programme, divided by the programme target population. We computed the AA-TAP for the CRC Italian screening programmes (biennial faecal immunochemical test, target population 50–69 year olds) using the data of the Italian National Survey from 2003 to 2016, overall and by region, and assessed the association between AA-TAP and CRC incidence fitting a linear regression between the trend of regional CRC incidence rates in 50–74 year old subjects and the cumulative AA-TAP.ResultsIn 2016, the AA-TAP at a national level was 105×100 000, whereas significant differences were observed between the northern and central regions (respectively 126 and 149×100 000) and the South and Islands (36×100 000). The cumulative AA-TAP from 2004 to 2012 was significantly correlated with the difference between CRC incidence rates in 2013–2014 and those in 2003–2004 (p=0.009).ConclusionThe AA-TAP summarises into a single indicator the potential impact of a screening programme in reducing CRC incidence rates.

Fire radiative energy density (FRED, J m−2) integrated from fire radiative power density (FRPD, W m−2) observations of landscape-level fires can present an undersampling problem when collected from fixed-wing aircraft. In the present study, the aircraft made multiple passes over the fire at ~3 min intervals, thus failing to observe most of the FRPD emitted as the flame front spread. We integrated the sparse FRPD time series to obtain pixel-level FRED estimates, and subsequently applied ordinary kriging (OK) and Gaussian conditional simulation (GCS) to interpolate across data voids caused by the undersampling. We compared FRED interpolated via OK and GCS with FRED estimated independently from ground measurements of biomass consumed from five prescribed burns at Eglin Air Force Base, Florida, USA. In four of five burns considered where undersampling prevailed, OK and GCS effectively interpolated FRED estimates across the data voids, improving the spatial distribution of FRED across the burning event and its overall mean. In a fifth burn, the burning characteristics were such that undersampling did not present a problem needing to be fixed. We also determined where burning and FRPD sampling characteristics merited applying OK and CGS only to the highest FRED estimates to interpolate more accurate FRED maps.

Remote sensing is increasingly being used as a cost-effective and practical solution for the rapid evaluation of impacts from wildland fires. The present study investigates the use of the support vector machine (SVM) classification method with multispectral data from the Advanced Spectral Emission and Reflection Radiometer (ASTER) for obtaining a rapid and cost effective post-fire assessment in a Mediterranean setting. A further objective is to perform a detailed intercomparison of available burnt area datasets for one of the most catastrophic forest fire events that occurred near the Greek capital during the summer of 2007. For this purpose, two ASTER scenes were acquired, one before and one closely after the fire episode. Cartography of the burnt area was obtained by classifying each multi-band ASTER image into a number of discrete classes using the SVM classifier supported by land use/cover information from the CORINE 2000 land nomenclature. Overall verification of the derived thematic maps based on the classification statistics yielded results with a mean overall accuracy of 94.6% and a mean Kappa coefficient of 0.93. In addition, the burnt area estimate derived from the post-fire ASTER image was found to have an average difference of 9.63% from those reported by other operationally-offered burnt area datasets available for the test region.

Fire radiative energy density (FRED, Jm-2) integrated from fire radiative power density (FRPD, Wm-2) observations of landscape-level fires can present an undersampling problem when collected from fixed-wing aircraft. In the present study, the aircraft made multiple passes over the fire at ~3min intervals, thus failing to observe most of the FRPD emitted as the flame front spread. We integrated the sparse FRPD time series to obtain pixel-level FRED estimates, and subsequently applied ordinary kriging (OK) and Gaussian conditional simulation (GCS) to interpolate across data voids caused by the undersampling. We compared FRED interpolated via OK and GCS with FRED estimated independently from ground measurements of biomass consumed from five prescribed burns at Eglin Air Force Base, Florida, USA. In four of five burns considered where undersampling prevailed, OK and GCS effectively interpolated FRED estimates across the data voids, improving the spatial distribution of FRED across the burning event and its overall mean. In a fifth burn, the burning characteristics were such that undersampling did not present a problem needing to be fixed. We also determined where burning and FRPD sampling characteristics merited applying OK and CGS only to the highest FRED estimates to interpolate more accurate FRED maps.

The Brazilian tropical moist forest biome (BTMFB) is experiencing high rates of deforestation and fire. Previous studies indicate that the majority of fires occur close to roads, however they did not consider the network of unofficial roads and navigable rivers, nor inter-state and inter-annual variability. We examine 8 years of Moderate Resolution Imaging Spectroradiometer (MODIS) active fire detections and the cumulative frequency distribution of the distance of each detection to the closest official road, unofficial road, and navigable river bank. Approximately 50 and 95% of all MODIS active fire detections occurred within 1 and 10 km respectively of a road or navigable river. Inter-state and inter-annual variations are discussed and linkages to expansion of the road network are suggested. Comparison of the distance distribution of the MODIS active fire detections and the distance distribution of a 0.5-km spaced geographic grid to the combined roads and navigable river network revealed significant differences for each state and for the BTMFB and indicate that the great majority of fires are anthropogenic. The results provide insights that may be useful for modelling the incidence of fire under future expansion of the Amazonian road network and increased river navigability.

Fire is a dynamic ecological process in forests and impacts the carbon (C) cycle through direct combustion emissions, tree mortality, and by impairing the ability of surviving trees to sequester carbon. While studies on young trees have demonstrated that fire intensity is a determinant of post-fire net primary productivity, wildland fires on landscape to regional scales have largely been assumed to either cause tree mortality, or conversely, cause no physiological impact, ignoring the impacted but surviving trees. Our objective was to understand how fire intensity affects post-fire net primary productivity in conifer-dominated forested ecosystems on the spatial scale of large wildland fires. We examined the relationships between fire radiative power (FRP), its temporal integral (fire radiative energy – FRE), and net primary productivity (NPP) using 16 years of data from the MOderate Resolution Imaging Spectrometer (MODIS) for 15 large fires in western United States coniferous forests. The greatest NPP post-fire loss occurred 1 year post-fire and ranged from −67 to −312 g C m−2 yr−1 (−13 to −54 %) across all fires. Forests dominated by fire-resistant species (species that typically survive low-intensity fires) experienced the lowest relative NPP reductions compared to forests with less resistant species. Post-fire NPP in forests that were dominated by fire-susceptible species were not as sensitive to FRP or FRE, indicating that NPP in these forests may be reduced to similar levels regardless of fire intensity. Conversely, post-fire NPP in forests dominated by fire-resistant and mixed species decreased with increasing FRP or FRE. In some cases, this dose–response relationship persisted for more than a decade post-fire, highlighting a legacy effect of fire intensity on post-fire C dynamics in these forests.

The Vocontian Basin in southeastern France records a long-lived history of subsidence and polyphase deformation at the junction of Alpine and Pyrenean orogenic systems. This study aims to reconstruct the tectonic, burial and thermal evolution of this basin, based on new U–Pb dating of calcite from veins and faults combined with new RSCM (Raman Spectroscopy of Carbonaceous Material) thermometry and stratigraphy-based burial models. Three main generations of calcite are identified: (1) the Late Cretaceous to Paleocene period related to the Pyrenean-Provençal convergence (∼ 84–50 Ma); (2) the Oligocene period linked to the extension of the West European Rift (∼ 30–24 Ma); and (3) the Miocene period, ascribed to strike-slip and compression associated with the Alpine collision (∼ 12–7 Ma). No older ages related to the Jurassic and Early Cretaceous rifting phase are obtained, despite targeted sampling near normal faults, suggesting highly localized syn-rift fluid circulation or dissolution of early calcite mineralization during subsequent tectonic events. RSCM data highlight a pronounced east–west thermal gradient. Peak temperatures are below 100 °C in the west and exceed 250 °C in the eastern basin, reflecting greater crustal thinning and salt diapirism in the eastern Vocontian Basin with the overlapping Jurassic and Cretaceous rifting phases. These results emphasize the significant impact of the West European Rift in south-eastern France. They further highlight the potential mismatch between large-scale tectonic processes and the tectonic history inferred from calcite U–Pb dating, which is sensitive to the presence of fluids and the physical conditions required for their preservation.