Carlos C. Dacamara

University of Lisbon | UL · Instituto Geofísico do Infante D. Luiz

The Fire Weather Index (FWI) is used to assess meteorological fire danger worldwide. It has been argued that it lacks an atmospheric instability term. A new enhanced FWI (FWIe) was recently developed incorporating atmospheric instability in the form of the Continuous Haines Index (CHI). Here, the first climatological and evolution analysis of these...

Portugal is regularly affected by destructive wildfires that have severe social, economic, and ecological impacts. The total burnt area in 2017 (∼540,000 ha) marked the all-time record value since 1980 with a tragic toll of 114 fatalities that occurred in June and October events. The local insurance sector declared it was the costliest natural disa...

Climate change is drastically altering the frequency, duration and severity of compound drought-heatwave (CDHW) episodes, which present a new challenge in environmental and socio-economic sectors. These threats are of particular importance in low-income regions with growing populations, fragile infrastructure, and threatened ecosystems. This review...

Owing to climate change-induced global warming, the frequency and duration of extremely hot events over the Iberian Peninsula (IP), such as heatwaves, are expected to continue to increase. This study shows the change of individual and monthly concurrent extremely hot events and burned area in the IP in the recent period of 1998–2015, compared with...

The year 2020 had the most catastrophic fire season over the last two decades in the Pantanal, which led to outstanding environmental impacts. Indeed, much of the Pantanal has been affected by severe dry conditions since 2019, with evidence of the 2020’s drought being the most extreme and widespread ever recorded in the last 70 years. Although it i...

O período entre 2018 e 2022 mostrou-nos que o problema dos incêndios à escala global não está a diminuir, antes pelo contrário. Parece que as consequências das alterações climáticas já estão a afectar a ocorrência de incêndios florestais em várias partes do Mundo, de uma forma que só esperaríamos que acontecesse vários anos mais tarde. Em muitos pa...

O período entre 2018 e 2022 mostrou-nos que o problema dos incêndios à escala global não está a diminuir, antes pelo contrário. Parece que as consequências das alterações climáticas já estão a afectar a ocorrência de incêndios florestais em várias partes do Mundo, de uma forma que só esperaríamos que acontecesse vários anos mais tarde. Em muitos pa...

O período entre 2018 e 2022 mostrou-nos que o problema dos incêndios à escala global não está a diminuir, antes pelo contrário. Parece que as consequências das alterações climáticas já estão a afectar a ocorrência de incêndios florestais em várias partes do Mundo, de uma forma que só esperaríamos que acontecesse vários anos mais tarde. Em muitos pa...

The Brazilian savanna (Cerrado) is considered the most floristically diverse savanna in the world, home to more than seven thousand species. The region is a mosaic of savannas, grasslands and forests whose unique biophysical and landscape attributes are on the basis of a recent ecoregional map, paving the way to improved region-based strategies for...

Mapping burned areas using satellite imagery has become a subject of extensive research over the past decades. The availability of high-resolution satellite data allows burned area maps to be produced with great detail. However, their increasing spatial resolution is usually not matched by a similar increase in the temporal domain. Moreover, high-r...

Climate extremes, poor management and lax laws are making this World Heritage Site prone to fierce fires. Researchers and governments must develop a plan to manage these risks together.

The Fire Weather Index (FWI) is widely used to assess the meteorological fire danger in several ecosystems worldwide. One shortcoming of the FWI is that only surface weather conditions are considered, despite the important role often played by atmospheric instability in the development of very large wildfires. In this work, we focus on the Iberian...

Fire is a natural disturbance in the Brazilian savannas, Cerrado, with substantial ecological and economic impacts. Most studies have characterized the fire regime in this biome using climate drivers but neglected the geographical variation of anthropogenic activities. These factors can trigger inappropriate fire-fighting decisions and biodiversity...

Dry lands are expected to cover about half of the terrestrial surface in the near future due to climate change. Drought events, which are recurrent over dry lands, are also projected to increase in both frequency and severity. There is a strong need to better monitor droughts over dry regions, and satellite-based indicators such as the Vegetation H...

Land surface emissivity is a directional quantity and most natural surfaces are anisotropic emitters. Experimental studies show that for homogeneous surfaces like bare soils, the emissivity decreases with view angle. Translation of the directionality of emissivity as obtained from experiments or models to satellite spatial scales of kilometers or m...

Over the past decades, methods for burned areas mapping and dating from remote sensing imagery have been the object of extensive research. The limitations of current methods, together with the heavy pre-processing of input data they require, make them difficult to improve or apply to different satellite sensors. Here, we explore a deep learning app...

Cerrado, one of the most important biodiversity global hotspots, is currently the main contributor to Brazil's annual burned area and, as a fire-dependent biome, it relies on fire to shape its vegetation distribution and structure. MATOPIBA, a region in Northeastern Cerrado, is the most recent agricultural frontier of Brazil and one of the last reg...

The Brazilian Cerrado vegetation has been increasingly threatened over the last decades and the significant loss of ~50% in its native cover is also related in part to the absence of a consistent fire policy in the region. Although the Cerrado is adapted to natural fires the significant changes in fire regimes might alter this biome irreparably. Wi...

Precipitation decline and vegetation fires in the Amazon region associated with climate change and deforestation expose local communities to hazardous air quality that may lead to damages in human health such as diseases of the respiratory system. Since 2000, drought incidence over the Amazon has been observed at a higher frequency than during the...

Portugal is recurrently affected by large wildfire events that have serious impacts at the socio-economic and environmental levels and dramatic consequences associated with the loss of lives and the destruction of the landscape. Accordingly, seasonal forecasts are required to assist fire managers, thus contributing to alter the historically based p...

Worldwide, fres have substantial economic, social and health-related impacts. Brazil is one of the most affected areas in the globe, particularly the Cerrado, a savanna-like biome, whose composition, structure, species abundance and diversity are shaped by recurring fres. The aim is to assess present and future trends of fre danger and burned area (...

We describe a methodology to discriminate burned areas and date burning events that use a burn-sensitive (V, W) index system defined in near-/mid-infrared space. Discrimination of burned areas relies on a monthly composite of minimum of W and on the difference between this composite and that of the previous month. The rationale is to identify pixel...

Fires have substantial economic, social and health related impacts worldwide. In fire-prone regions, such as the Brazilian savanna (cerrado), fire shapes ecosystem composition and structure, influencing species abundance and diversity. Therefore, it is crucial to understand how climate-change might affect fire patterns in the coming decades. Relyin...

Fire is one of the most important disturbance agents as it strongly influences climate, the carbon cycle and global vegetation patterns. As a fire-prone biome, the Brazilian cerrado is adapted to and relies on seasonal fire activity to shape its structure and composition. However, high severity fires and vast burned area extent can still irreparabl...

Portugal is recurrently affected by large wildfire events that have serious impacts at the socio-economic and environmental levels and dramatic consequences associated with the loss of lives and the destruction of the landscape. Accordingly, seasonal forecasts are required to assist fire managers, thus contributing to alter the historically-based p...

Most available long-term databases of land surface temperature (LST) derived from space-borne sensors rely on infrared observations and are therefore restricted to clear-sky conditions. Hence, studies based on such data sets may not be representative of all-weather conditions and may be considered as “biased” toward clear sky. An assessment of the...

Cellular Automata have been successfully applied to simulate the propagation of wildfires with the aim of assisting fire managers in defining fire suppression tactics and in designing fire risk management policies. We present a Cellular Automata designed to simulate a severe wildfire episode that took place in Algarve (southern Portugal) in July 20...

The Vegetation Health Index (VHI) has been widely used for monitoring and characterising droughts. This index takes into account ecosystem features in terms of fluctuations between prescribed maxima and minima of NDVI (Vegetation Condition Index, VCI) and of Land Surface Temperature (LST; Thermal Condition Index, TCI), and is estimated as the weigh...

The Vegetation Health Index (VHI) is widely used for monitoring drought using satellite data. VHI depends on vegetation state and thermal stress, respectively assessed via (i) the Vegetation Condition Index (VCI) that usually relies on information from the visible and near infra-red parts of the spectrum (in the form of Normalized Difference Vegeta...

The correction of directional effects on satellite-retrieved land surface temperature (LST) is of high relevance for a proper interpretation of spatial and temporal features contained in LST fields. This study presents a methodology to correct such directional effects in an operational setting. This methodology relies on parametric models, which ar...

A previously developed procedure that aims at monitoring the process of vegetation recovery in areas afected by major fire episodes is revisited and assessed in terms of consistency and robustness. The procedure is based on 10-day fields of Maximum Value Composites of the Normalised Difference Vegetation Index (MVC-NDVI). The identification of fire...

Land surface temperature (LST) values retrieved from satellite measurements in the thermal infrared (TIR) may be strongly affected by spatial anisotropy. Different parametric approaches have been proposed to simulate such effects. These are relatively simple models requiring few input data and therefore appropriate to simulate directional effects i...

We present a procedure that allows the operational generation of daily forecasts of fire danger over Mediterranean Europe. The procedure combines historical information about radiative energy released by fire events with daily meteorological forecasts, as provided by the Satellite Application Facility for Land Surface Analysis (LSA SAF) and the Eur...

We present a procedure that allows the operational generation of daily forecasts of fire danger over Mediterranean Europe aiming to improve state-of-the art modelling skills for classes of high fire danger. The procedure combines historical information about radiative energy released by fire events with daily meteorological forecasts, as provided b...

An automated procedure is here presented that allows identifying and dating burned areas in Portugal using values of daily reflectance from near-infrared and middle-infrared bands, as obtained from the MODIS instrument. The algorithm detects persistent changes in monthly composites of the so-called (V,W) Burn- Sensitive Index and the day of maximum...

Southern European countries are particularly affected by summer wildfires and drought events. The occurrence of extreme meteorological conditions during preceding and contemporaneous months amplifies the risk of summer wildfires. The main scope of this study was to investigate the impact of drought periods on burned areas in the Iberian Peninsula....

Climate change is expected to have a significant impact on fire occurrence and activity, particularly in Brazil, a region known to be fire-prone [1]. The Brazilian savanna, commonly referred to as cerrado, is a fire-adapted biome covering more than 20% of the country's total area. It presents the highest numbers of fire events, making it particular...

In fire-sensitive ecosystems, fires are recurrent and can disrupt ecological processes, alter its structure and composition, biogeochemical cycles, atmospheric chemistry and composition, as well as human health. As Brazil is one of the areas with the highest number of fire occurrences it becomes essential to understand the evolution of fire under c...

Abstract Land surface temperature (LST) is a markedly directional variable and its remotely sensed measurement may be strongly affected by viewing and illumination geometries. This study proposes the use of LST products collocated in space and time, but obtained with different viewing angles, to calibrate a simple model capable of characterizing th...

A comparison of land surface temperature (Ts) derived from the Advanced Microwave Scanning Radiometer - Earth observation system (AMSR-E) with infrared Ts is presented. The infrared Ts include clear-sky estimates from the MODerate resolution Imaging Spectroradiometer (MODIS), the Spinning Enhanced Visible and Infrared Imager (SEVIRI), the Geostatio...

Algorithms for Land Surface Temperature (LST) retrieval from infrared measurements are usually sensitive to the amount of water vapor present in the atmosphere. The Satellite Application Facilities on Climate Monitoring and Land Surface Analysis (CM SAF and LSA SAF) are currently compiling a 25 year LST Climate data record (CDR), which uses water v...

Fire has a significant contribution to the global greenhouse gas emissions and vast ecological and climatic impacts. Worldwide, Brazil is one of the areas most affected by fire, which highly influences the state of the vegetation cover, the ecological diversity of the region and has significant consequences to the global CO balance [1]. Hence, with...

The changes induced by human impact in the climate system are expected to increase the likelihood of extreme events and disturbances, such as fire, whose impacts may further contribute to climate change. Brazil is one of the areas more severely affected by fire occurrences. At the same time, it holds the largest area of tropical forest. As fire in...

Remote sensing from spaceborne sensors combining near- and middle-infrared information has proved to be an efficient means to monitor the effects of vegetation fires. Burn-sensitive spectral indices, such as the (V, W) index system, have been developed and successfully applied for burned area discrimination. The (V, W) index system provides useful...

Land Surface Temperature (LST) is routinely retrieved from remote sensing instruments using semi-empirical relationships between top of atmosphere (TOA) radiances and LST, using ancillary data such as total column water vapor or emissivity. These algorithms are calibrated using a set of forward radiative transfer simulations that return the TOA rad...

Land Surface Temperature (LST) is routinely retrieved from remote sensing instruments using semi-empirical relationships between top of atmosphere (TOA) radiances and LST, using ancillary data such as total column water vapor or emissivity. These algorithms are calibrated using a set of forward radiative transfer simulations that return the TOA rad...

Fire has a fundamental role in the Earth system as it influences global and local ecosystem patterns and processes, such as vegetation distribution and structure, the carbon cycle and climate. Since, in the global context, Brazil is one of the regions with higher fire activity, an assessment is here performed of the sensitivity of the wildfire regi...

In the global context, Brazil is one of the regions more severely affected by fire occurrences, with important consequences in the global CO2 balance, the state of the Amazon forest and the ecological diversity of the region. Brazil is also one of the few regions experiencing a raise in annual mean temperature above 2.5o during the 20th century, wh...

Although Cerrado is a fire-dependent biome, current agriculture practices have significantly modified the native fire regime. Moreover, over the last decades, climate conditions, such as intensive droughts, have contributed to enhance the effects of anthropogenic activities, and consequently fire, over the region. For instance, during the 2010 extr...

The Brazilian Cerrado is significantly affected by anthropic fires every year, which makes the region an important source of pyrogenic emissions. This study aims at generating improved 1 km monthly burned area maps for Cerrado based on remote-sensed information. The algorithm relies on a burn-sensitive vegetation index based on MODIS daily values o...

Fire has a fundamental role in the Earth system as it influences global and local ecosystem patterns and processes, such as vegetation distribution and structure, the carbon cycle and climate. In Brazil, fire has major ecological and economic impacts, such as the costs associated with the adverse health effects of smoke haze. In the coming decades,...

The European Organization for the Exploitation of Meteorological Satellites' (EUMETSAT) Meteosat satellites provide the unique opportunity to compile a 30+ year land surface temperature (LST) climate data record. Since the Meteosat instrument on-board Meteosat 2-7 is equipped with a single thermal channel, single-channel LST retrieval algorithms ar...

Active fire information provided by TERRA and AQUA instruments on-board sun-synchronous polar MODIS platform is used to describe fire activity in the Western Mediterranean and to identify and characterize the synoptic patterns of several meteorological fields associated with the occurrence of extreme fire activity episodes (EEs). The spatial distri...

This database contains detailed description of the uncertainty associated with the variables / parameters commonly used to simulate fire spread with the FARSITE modelling system. The database supports the following publication: Benali et al. 2015. Deciphering the impact of uncertainty in the accuracy of large wildfires’ spread simulations. Submitte...

Brazil contributes as a source of greenhouse gases, aerosols and trace gases to the atmosphere, in particular, due to the continuous conversion of vegetation to pasture and agriculture land using fire practices. Although the Brazil presents huge numbers of fire events, there is a lack of studies in order to analyze the agreement among currently ava...

We present a validation of three MODIS burned area products, namely AQM/INPE, MCD45A1/NASA and MCD64A1/NASA, covering a 6-year period (2005-2010) over Jalapão, a fire-prone region located in the Cerrado. As reference we use high resolution BA maps derived from Landsat imagery. Because the products to be validated have different spatial resolutions...

Southern European countries, and the Iberian Peninsula (IP) in particular, have been vastly affected by summer wildfires (Trigo et al., 2013). This condition is hampered by the frequent warm and dry meteorological conditions found in summer which play a significant role in the triggering and spreading of wildfires. These meteorological conditions a...

Europe has suffered several extreme weather events which were responsible for considerable ecological and economic losses in the last few decades. In Southern Europe, droughts are one of the most frequent extreme weather events, causing severe damages and various fatalities. The main goal of this study is to determine the role of Circulation Weathe...

This work presents an automated regional algorithm that allows detecting burned areas in Brazil based on information from TERRA/AQUA MODIS data. The procedure relies on the so-called W burning index, that requires daily reflectance from the 1km MODIS Level 1B calibrated radiance from bands 2 (near infrared) and 20 (middle infrared). Burned pixels a...

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Representing more than 85% of burned area i