Surface moisture and temperature trends anticipate drought conditions linked to wildfire activity in the Iberian Peninsula

In this study, drought conditions involving risk of fires are detected applying SMOS-derived soil moisture data and land surface temperature models. Moisture-temperature (SM-LST) patterns studied between 2010 and 2014 were linked to main fire regimes in the Iberian Peninsula. Most wildfires burned in warm and dry soils, but the analysis of pre-fire conditions differed among seasons. Absolute values of SM-LST were useful to detect prone- to-fire conditions during summer and early autumn. Complementarily, SM-LST anomalies were related to droughts and high fire activity in October 2011 and February-March 2012. These episodes were coincident with abnormally anticyclonic atmospheric conditions. Results show that combined trends of new soil moisture space-borne data and temperature models could enhance fire risk assessment capabilities. This contribution should be helpful to face the expected increase of wildfire activity derived from climate change.Peer ReviewedPostprint (published version

Predicting the extent of wildfires using remotely sensed soil moisture and temperature trends

©2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Recent climate trends evidence a rise of temperatures and an increase in the duration and intensity of droughts which is in turn leading to the occurrence of larger wildfires, which threaten the environment as well as human lives and beings. In this context, improved wildfires prediction tools are urgently needed. In this paper, the use of remotely sensed soil moisture data as a key variable in the climate-wildfires relationship is explored. The study is centered in the fires registered in the Iberian Peninsula during the period 2010-2014. Their prior-to-occurrence surface moisture-temperature conditions were analyzed using SMOS-derived soil moisture data and ERA-Interim land surface temperature reanalysis. Results showed that moisture and temperature conditions limited the extent of wildfires, and a potential maximum burned area per moisture-temperature paired values was obtained (R-2=0.43). The model relating fire extent with moisture-temperature preconditions was improved by including information on land cover, regions, and the month of the fire outbreak (R-2=0.68). Model predictions had an accuracy of 83.3% with a maximum error of 40.5 ha. Results were majorly coherent with wildfires behavior in the Iberian Peninsula and reflected the duality between Euro-Siberian and Mediterranean regions in terms of expected burned area. The proposed model has a promising potential for the enhancement of fire prevention services.Peer ReviewedPostprint (author's final draft

Trend in vegetational cover affected by fire in the Torres del Paine National Park

[EN] Torres del Paine National Park (PNTP) is characterized as a representative geographical area of the world’s ecosystems, containing high scenic beauty and wide variety of ecosystems. The aim of this work is to analyze the spatial and temporal trends of vegetation at PNTP using remote images from the Landsat platforms, the MOD13A3 product from the Moderate Resolution Imaging Spectroradiometer (MODIS), coverage maps surface Global Land cover Maps of ESA/CCI 2005 and 2010 and a land cover map of continental Chile of 2014. In addition, the products of Soil Moisture and Ocean Salinity (SMOS) and meteorological data from the Torres del Paine meteorological station were used to analyze the environmental conditions that presented the park while the fire occurred the years 2011-2012. To determine the magni­tude of the changes of vegetation affected by fire at PNTP a nonparametric trend analysis was use with the Normalized Difference Vegetation Index (NDVI) of MODIS from 2002 to 2016 and the Normalized Burn Ratio (NBR) for the fire occurred the year 2005 and the years 2011-2012. The results show that between both fires it is been affected more than 30.000 hectares of the national park, being the “Scrub” and “Forest” coverage the most affected due to the high level of severity and the low regeneration of the burn area (less than 56%). The soil moisture does not exceed 20% m3m-3 before the fire and the rainfall does not exceed 101 mm during the days of fire, which is related to an increase in the probability of propa­gation of the fire. In this work is possible to realize that remote sensing can be used in the fire management to regard the national parks with the objective of preserve and conserve the flora, fauna and scenic beauty of Chile.[ES] El Parque Nacional Torres del Paine (PNTP) se caracteriza por ser un área geográfica representativa de los ecosistemas del mundo, al contener una alta belleza paisajística y amplia diversidad de ecosistemas. El objetivo de este trabajo es analizar las tendencias espacio temporales de la vegetación en el PNTP mediante el uso de imágenes remo­tas de la plataforma Landsat, del sensor “Moderate Resolution Imaging Spectroradiometer” (MODIS), correspondientes al producto MOD13A3, los mapas de cobertura de superficie Global Land Cover Maps del ESA/CCI del año 2005 y 2010 y el mapa de cobertura de suelo de Chile continental del 2014. Además, se utilizaron los productos de “Soil Moisture and Ocean Salinity” (SMOS), y datos meteorológicos de la estación meteorológica Torres del Paine para analizar las condiciones ambientales que presentó el parque mientras ocurría el incendio de los años 2011-2012. Para determinar la magnitud de los cambios de la vegetación afectada por incendio del PNTP se realizó un análisis no paramétrico de la tendencia del índice “Normalized Difference Vegetacion Index” (NDVI) de MODIS en el periodo 2002 a 2016 y el índice “Normalized Burn Ratio” (NBR) para los incendios de los años 2005 y 2011-2012. Los resultados muestran que los incendios 2005 y 2011-2012 afectaron a más de 30.000 hectáreas del Parque Nacional, siendo las coberturas de “Matorral” y “Bosque” las más afectadas debido a su alto nivel de severidad y su regeneración menor al 56% de la superficie afectada. En cuanto a la humedad de suelo esta no supera los 20% m3m–3 antes del incendio y las precipitaciones no superan los 101 mm durante los días de incendio lo que se relaciona con un aumento en las probabilidades de propagación del incendio. En este trabajo se evidencia que la teledetección puede ser utilizada en la gestión de incendios y así resguardar los parques nacionales con el fin de preservar y conservar la flora, fauna y belleza paisajística de Chile.Gracias al proyecto Conicyt – Fondecyt Iniciación 11130359 “Estimating the Surface soil moisture at regional scale by using a synergic optical-passive microwave approach and remote sensing data”, a United States Geological Survery (USGS) por el libre acceso a los datos Landsat-5 TM, Landsat-7 ETM+ y Landsat-8 OLI, a la National Aeronautics and Space (NASA) por los productos MODIS y la Dra. María Piles por los productos de humedad de suelo SMOS.Rivera, C.; Mattar, C.; Durán-Alarcón, C. (2017). Tendencia de la cobertura vegetacional afectada por incendios en el Parque Nacional Torres del Paine. Revista de Teledetección. (50):71-87. https://doi.org/10.4995/raet.2017.7422SWORD71875

Low soil moisture and high temperatures as indicators for forest fire occurrence and extent across the Iberian Peninsula

Fires are a concerning topic in Mediterranean areas. They are increasing in number and extension, probably due to the anomalous dry and hot conditions experienced in this region in the last decade. In this study, more than 2,000 fires that took place in the Iberian Peninsula (2010-2014) were analyzed. The new all-weather version of SMOS-derived soil moisture product at fine scale resolution, as well as ERA-Interim Skin Temperature datasets, were used. Soil moisture and temperature anomalies based in these datasets were computed and included in the database. These information allowed analyzing prior-to-fire conditions. Results reported that more than 70% of fires started under dry and hot conditions, and this percentage rose till 94% in the anomalous conditions prior to the biggest fires. A relation between soil moisture, temperature and burned area is found which could set the basis for a fire risk index based on SMOS data and temperature information.Peer Reviewe