Health and Economic Burden of the 2017 Portuguese Extreme Wildland Fires on Children

Wildland fires release substantial amounts of hazardous contaminants, contributing to a decline in air quality and leading to serious health risks. Thus, this study aimed to understand the contributions of the 2017 extreme wildland fires in Portugal on children health, compared to 2016 (with burned area, in accordance with the average of the previous 15 years). The impact of long-term exposure to PM10 and NO2 concentrations, associated with wildland fires, on postneonatal mortality, bronchitis prevalence, and bronchitis symptoms in asthmatic children was estimated, as well as the associated costs. The excess health burden in children attributable to exposure to PM10 and NO2, was calculated based on WHO HRAPIE relative risks. Fire emissions were obtained from the Fire INventory from NCAR (FINN). The results obtained indicate that the smoke from wildfires negatively impacts children’s lung function (PM10 exposure: increase of 320 and 648 cases of bronchitis in 2016 and 2017; NO2 exposure: 24 and 40 cases of bronchitis symptoms in asthmatic children in 2016 and 2017) and postneonatal mortality (PM10 exposure: 0.2 and 0.4 deaths in 2016 and 2017). Associated costs were increased in 2017 by around 1 million € for all the evaluated health endpoints, compared to 2016.

A dominant contribution to light absorption by methanol-insoluble brown carbon produced in the combustion of biomass fuels typically consumed in wildland fires in the United States

The light-absorption properties of brown carbon (BrC) are often estimated using offline, solvent-extraction methods. However, recent studies have found evidence of insoluble species of BrC which are unaccounted for in...

Incorporating Sentinel-1 SAR imagery with the MODIS MCD64A1 burned area product to improve burn date estimates and reduce burn date uncertainty in wildland fire mapping

Wildland fires result in a unique signal detectable by multispectral remote sensing and synthetic aperture radar (SAR). However, in many regions, such as Southeast Asia, persistent cloud cover and aerosols temporarily obstruct multispectral satellite observations of burned area, including the MODIS MCD64A1 Burned Area Product (BAP). Multiple days between cloud free pre- and postburn MODIS observations result in burn date uncertainty. We incorporate cloud-penetrating, C-band SAR-with the MODIS MCD64A BAP in Southeast Asia, to exploit the strengths of each dataset to better estimate the burn date and reduce the potential burn date uncertainty range. We incorporate built-in quality control using MCD64A1 to reduce erroneous pixel updating. We test the method over part of Laos and Thailand during April 2016 and found average uncertainty reduction of 4.5 d, improving 15% of MCD64A1 pixels. A new BAP could improve monitoring temporal trends of wildland fires, air quality studies and monitoring post-fire vegetation dynamics.

Southwestern ponderosa pine forest patterns following wildland fires managed for resource benefit differ from reference landscapes

Context. Managers aiming to utilize wildland fire to restore southwestern ponderosa pine landscapes require better understanding of forest cover patterns produced at multiple scales. Restoration effectiveness of wildland fires managed for resource benefit can be evaluated against natural ranges of variation.Objectives. We describe landscape patterns within reference landscapes, including restored and functioning ponderosa pine forests of northern Arizona, and compare them to wildland fires managed for resource benefit. We make comparisons along a gradient of extents and assess the effects of scale on landscape differences.Methods. Using Sentinel-2 imagery, we classified ponderosa pine forest cover and calculated landscape metrics across a gradient of landscape extent within reference and managed landscapes. We used non-parametric tests to assess differences. We used random forest models to assess and explore which landscape metrics were most importance in differentiating landscape patterns.Results. Managed wildfire landscapes were significantly different from reference landscapes for most metrics and extents (15 ha to 840 ha). Landscape type (managed vs. reference) became increasingly differentiable with scale, with area and aggregation metrics being the most informative. Classification models increased in accuracy despite fewer observations with increasing scale.Conclusions. Wildland fires managed for resource benefit in ponderosa pine forests of northern Arizona are not producing landscape patterns consistent with reference landscapes likely due to predominance of low-severity burning and minimal resulting changes in overstory structure. Differences become more pronounced with increasing landscape size and suggest small-scale heterogeneity and mid - and large-scale homogeneity within each landscape type.