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The 9th International Conference on Forest Fire Research, organised by the Forest Fire Research Center of the Association for Developmental of Industrial Aerodynamics every 4 years since 1990, was held in November 2022 in Coimbra, Portugal. The conference was held in conjunction with the 17th International Wildland Fire Safety Summit, sponsored by the International Association of Wildland Fire. The number and quality of the submissions for this joint event was very high, and the authors were encouraged to submit a full paper to a special issue of the International Journal of Wildland Fire (IJWF). Given the large number of submissions, the Journal decided to publish the special issue in four parts. Part 1 was published in January 2023, with eight papers, Part 2 in March 2023, with 10 papers and Part 3 in June 2023 with 15 papers. This fourth part presents 10 original papers, in three areas: Decision Support Systems and Tools (3), Risk Assessment & Reduction (3) and the Wildland Urban Interface (4). All the papers in this special issue are published Open Access. Part 4 of the special issue that resulted from the 9th International Conference on Forest Fire Research includes 10 papers on various aspects of wildland fire research. Parts 1, 2 and 3 were published in January, March and June 2023 respectively. All papers in the special issue are published Open Access. [ABSTRACT FROM AUTHOR]

The ninth International Conference on Forest Fire Research, organised by the Forest Fire Research Center of the Association for Developmental of Industrial Aerodynamics every 4 years since 1990, was held in November 2022 in Coimbra, Portugal. The conference was held in conjunction with the 17th International Wildland Fire Safety Summit, sponsored by the International Association of Wildland Fire. The number and quality of the submissions for this joint event was very high, and the authors were encouraged to submit a full paper to a special issue of the International Journal of Wildland Fire (IJWF). Given the large number of submissions, the Journal decided to publish the special issue in several parts. Part 1 was published in January 2023, with eight papers, and Part 2 in March 2023, with 10 papers. This third part presents 15 original papers in five topical areas: decision support systems and tools (3), risk reduction (2), risk assessment (3), wildland urban interface (3) and wildfire management and safety (4). All the papers in this special issue are published Open Access. [ABSTRACT FROM AUTHOR]

The ninth International Conference on Forest Fire Research (ICFFR) was recently held in Coimbra, Portugal, bringing together scientists and fire managers from around world to advance and update knowledge in the area of fire management. The conference was held jointly with the International Association of Wildland Fire's 17th International Wildland Fire Safety Summit (IWFSS). Here we introduce Part 1 of a special issue series arising from the 2022 ICFFR/IWFFS joint meeting. This issue of the International Journal of Wildland Fire contains eight papers covering a wide variety of topics including: seasonal fire activity and spatio-temporal fire-weather patterns under climate change, the role of atmospheric conditions on fire and flaming zone behaviour, analytical techniques for measuring oxidative pyrolysis gases, particulate morphology of fires in the wildland–urban interface, deep peat fire smouldering and the impact of post-fire treatments on soil. All papers in the issue are published Open Access. Here we introduce Part 1 of a special issue series arising from the IX International Conference on Forest Fire Research, held 14–18 November 2022, Coimbra, Portugal. This issue comprises eight papers covering a wide variety of topics. All papers in the issue are published Open Access. [ABSTRACT FROM AUTHOR]

The article presents a study which investigates the homogenization of long-term temperature data series in Porto, Lisbon, and Coimbra, Portugal. The study used metadata, a visual analysis, and homogeneity tests. Results show that all the data series have both internal climatic and non-climatic origins.

Background and aims: Infrared thermal images of a propagating wildfire taken by manned or unmanned aerial vehicles can help firefighting authorities with combat planning. Segmenting these images into regions of different fire temperatures is a necessary step to measure the fire perimeter and determine the location of the fire front. Methods: This work proposes a multilayer segmentation method based on level sets, which have the property of handling topology, making them suitable to segment images that contain scattered fire areas. The experimental results were compared using hand-drawn labels over a set of images provided by the Portuguese Air Force as ground truth. These labels were carefully drawn by the authors to ensure that they complied with the requirements indicated by the Portuguese National Authority for Emergency and Civil Protection. The proposed method was optimised to ensure contour smoothness and reliability, as well as reduce computation time. Key results: The proposed method can surpass other common unsupervised methods in terms of intersection over union, although it has not yet been able to perform real-time segmentation. Conclusions: Although falling out of use in relation to supervised and deep learning methods, unsupervised segmentation can still be very useful when annotated datasets are unavailable. The infrared thermal images of a propagating wildfire taken by aerial vehicles can help firefighting authorities in combat planning. We propose a method that is able to separate the wildfire into different temperature regions, which facilitates identification of the fire perimeter and location of the active front. (This paper is part of a Special Issue that includes papers on research presented at the IX International Conference on Forest Fire Research, Coimbra, Portugal, November 2022.) [ABSTRACT FROM AUTHOR]

Background: In Pedrógão Grande on 17 June 2017, two fire fronts merged and the propagation of the fire was influenced by the interaction of these non-symmetric fire fronts. Aims: This wildfire motivated us to study a junction fire with two non-symmetrical fire fronts. The analysis of the movement of the intersection point and the angle (γ) between the bisector of the fire lines and the maximum rate of spread (ROS) direction is of particular relevance. Methods: The study was carried out at Forest Fire Laboratory of the University of Coimbra in Lousã (Portugal) with laboratory experiments. Key results: We found that, for small rotation angles (δ), the non-dimensional ROS of the intersection point depends on the slope angle (α) and the initial angle between fire fronts. Conclusions: For high α , the non-dimensional ROS was highly influenced by the convection process and γ where the maximum ROS occurred, increased when δ increased. However, the radiation process was more relevant for lower α and influenced the non-dimensional ROS. For these cases, the maximum spread direction was close to that of the fire line bisector. Implications: The present work aimed to explain fire behaviour during the Pedrógão Grande wildfire. In Pedrógão Grande on 17 June 2017, two fire-fronts merged and propagation of the fire was influenced by the interaction of these non-symmetric fire fronts. We found that the rate of spread for small rotation depended on the slope angle and the initial angle between fire fronts. (This paper is part of a Special Issue that includes papers on research presented at the IX International Conference on Forest Fire Research, Coimbra, Portugal, November 2022.) [ABSTRACT FROM AUTHOR]

Background: Wildfires are a growing threat to many ecosystems, bringing devastation to human safety and health, infrastructure, the environment and wildlife. Aims: A thorough understanding of the characteristics determining the susceptibility of an area to wildfires i s crucial to prevention and management activities. The work focused on a case study of 13 countries in the eastern Mediterranean and southern Black Sea basins. Methods: A data-driven approach was implemented where a decade of past wildfires was linked to geoclimatic and anthropic descriptors via a machine learning classification technique (Random Forest). Empirical classification of fuel allowed linking of fire intensity and hazard to environmental drivers. Key results: Wildfire susceptibility, intensity and hazard were obtained for the study area. For the first time, the methodology is applied at a supranational scale characterised by a diverse climate and vegetation landscape, relying on open data. Conclusions: This approach successfully allowed identification of the main wildfire drivers and led to identification of areas that are more susceptible to impactful wildfire events. Implications: This work demonstrated the feasibility of the proposed framework and settled the basis for its scalability at a supranational level. In this work, wildfire susceptibility, intensity and risk were obtained for the eastern Mediterranean and southern Black Sea basins. A methodology that combines machine learning techniques and empirical modelling is applied at a supranational scale characterised by a diverse climate and vegetation landscape, relying on open data. (This paper is part of a Special Issue that includes papers on research presented at the IX International Conference on Forest Fire Research, Coimbra, Portugal, November 2022.) [ABSTRACT FROM AUTHOR]

Background: In most wildland–urban interface (WUI) fires, damage to buildings results from poor surrounding vegetation management. No simulation had been conducted yet on historical WUI fires with Computational Fluid Dynamics modelling. Aims: It was interesting to check the feasibility of this modelling in simulating past fire cases for different scenarios of vegetation management and fire propagation. Methods: We studied three cases of WUI dwellings surrounded by gardens (subject to French regulations on fuel reduction) adjacent to forest affected by a past fire. The 3D fire propagation was assessed using the Fire Dynamic Simulator model (FDS) and taking into account accurate fire environment (fine vegetation distribution, terrain, etc.). Key results: Results showed that, in the current model state, brush-clearing mitigated fire intensity and propagation and damage to ornamental vegetation. However, it sometimes highlighted that this measure could be strengthened when the effects of topography and wind were combined. Conclusions: FDS modelling at the WUI scale using accurate vegetation distribution proved to be functionally satisfactory, exhibiting realistic fire behaviour. Implications: Once validated, this modelling will ultimately help to assess when fuel reduction is efficient in fire mitigation and to pinpoint possible limitations. Modelling past fire behaviour using FDS at WUI scale taking into account refined vegetation distribution has rarely been attempted. The modelling was compared with past fire behaviour using different scenarios of vegetation management, sometimes highlighting that fuel reduction regulations could be strengthened when there is synergy between topography and wind. (This paper is part of a Special Issue that includes papers on research presented at the IX International Conference on Forest Fire Research, Coimbra, Portugal, November 2022.) [ABSTRACT FROM AUTHOR]

Background: Embers, also known as firebrands, are the leading cause of building ignition during wildland–urban fires. This is attributed both to direct ignition of material on, in, or attached to the building, and indirect ignition where they ignite vegetation or other combustible material near the building, which results in a radiant heat and/or direct flame contact exposure that ignites the building. Indirect ignition of a building can occur when embers accumulate on and ignite nearby combustible fuel, resulting in radiant heat or flame constant exposure. Aims/implications: Factors that influence ember accumulation near a building include building geometry, such as flat wall and re-entrant corners, building wind angle, wind speed and the surface roughness characteristics of the horizontal landscape close to the building. Methods: Experiments conducted at the Insurance Institute for Business & Home Safety (IBHS) Research Center using full-scale buildings with the above-mentioned factors provided a means to quantify ember accumulation on a mass per unit area basis. Key results: Ember accumulation was greatest at locations immediately adjacent to the building and higher wind speeds allowed more embers to reach the building. Conclusions: The work presented in this paper provides data and insight on wind-blown ember accumulation near a full-scale building. Full-scale experiments were conducted to study the factors that influence ember accumulation near a building including building geometry, such as flat wall and re-entrant corners, building wind angle, wind speed and the surface roughness characteristics of the horizontal landscape close to the building. (This paper is part of a Special Issue that includes papers on research presented at the IX International Conference on Forest Fire Research, Coimbra, Portugal, November.) [ABSTRACT FROM AUTHOR]

Background: Lightning is the most common origin of natural fires, being strongly linked to specific synoptic conditions associated with atmospheric instability, such as dry thunderstorms; dry fuels are required for ignition to take place and for subsequent propagation. Aims: The aim was to predict the daily probability of ignition by exploiting a large dataset of lightning and fire data to anticipate ignition over the entire Iberian Peninsula. Methods: We trained and tested a machine learning model using lightning strikes (>17 million) in the period 2009–2015. For each lightning strike, we extracted information relating to fuel condition, structural features of vegetation, topography, and the specific characteristics of the strikes (polarity, intensity and flash density). Key results: Naturally triggered ignitions are typically initiated at higher elevations (above 1000 m above sea level) under conditions of low dead fuel moisture (<10–13%) and moderate live moisture content (Drought Code > 300). Negative-polarity lightning strikes (−10 kA) appear to trigger fires more frequently. Conclusions and implications: Our approach was able to provide ignition forecasts at multiple temporal and spatial scales, thus enhancing forest fire risk assessment systems. Natural wildfires on the Iberian Peninsula are caused by lightning strikes reaching locations with abundant vegetation, and are favoured by drought conditions that lower the moisture content of the fuels. Here, we developed a model able to forecast and map the likelihood of ignition at a daily timescale. (This paper is part of a Special Issue that includes papers on research presented at the IX International Conference on Forest Fire Research, Coimbra, Portugal, November 2022.) [ABSTRACT FROM AUTHOR]

Background: Jet fires and boiling liquid expanding vapour explosions (BLEVEs) are potential events when a vessel containing liquefied petroleum gas (LPG) is exposed to fire. Events involving domestic LPG tanks have occurred at wildland–urban interface areas in Portugal, the USA, Spain and Greece. Aims: Evaluation of the pressure relief device (PRD), the type of cylinder and the effects of jet fires and BLEVEs. Methods: LPG cylinders manufactured with steel and composite materials were exposed to fire. Hydrostatic tests were carried out to compare the burst pressure without fire influence. Fourteen accidents that occurred during wildfires are described. Key results: The presence of a PRD and the right choice of type of cylinder as well as cylinder location may avert major accidents. The jet fires and fireball radiation are also described, as well as the maximum distance reached by cylinder fragments. Conclusions: The tests showed that the burst pressure in the test of a cylinder without PRD under fire was significantly lower when compared with the hydrostatic tests. Implications: Lastly, recommendations to avoid accidents are made. In the present experimental study, 14 accidents related to LPG stored at the wildland–urban interface that occurred during wildfires are described. Tests with LPG cylinders exposed to fire using forest fuels were done to evaluate the safety devices and effects of explosions and jet fire. (This paper is part of a Special Issue that includes papers on research presented at the IX International Conference on Forest Fire Research, Coimbra, Portugal, November 2022.) [ABSTRACT FROM AUTHOR]

Background: Swedish wildfires are handled by multipurpose municipal rescue services, raising questions about how non-specialist incident commanders (ICs) perceive and interpret wildfire behaviour. Aims: Elucidating ICs' interpretations of fire behaviour, fuel complexes, weather, landscape structure and the role of these in tactical decisions. Methods: We exposed Swedish ICs to questionnaires and tabletop exercises for different standardised fire scenarios. Key results: Despite minimal formal wildfire training, ICs showed reasonable consensus in rating of fuels, fire behaviour, hose-lay production rates, etc. Tactics were to access the fire from the nearest road with hose-line laid from the engine and water ferried on trucks. In a scenario where initial attack failed, they typically fell back to roads, without burning off. This indicates a fundamental flaw in tactics employed for high-intensity fires, which easily breach forestry roads, and invite outflanking. Conclusions: The IC wildfire knowledge is built on personal and group experience rather than formal education. We found reasonable competence, despite the organisations being designed primarily for other purposes. However, tactical understanding of complex, large incidents was poor. IC training should emphasise potential hazards of such incidents to enhance group competence despite their low frequency. Implications: Standardised tabletop exercises can provide insight into decision-making of ICs that is otherwise hidden. In regions with high wildfire potential but a low frequency of complex incidents, perceptions of wildfire behaviour can vary significantly among incident commanders. This study shows how incident commanders' a priori understanding of wildfire affects their decisions during incidents, and how tabletop exercises can be used to extract such information. (This paper is part of a Special Issue that includes papers on research presented at the IX International Conference on Forest Fire Research, Coimbra, Portugal, November 2022.) [ABSTRACT FROM AUTHOR]

Background: This paper identifies the weaknesses of the Portuguese approach to promote wildfire risk reduction through spatial planning. Aims: This paper contributes to bridging a critical gap in knowledge on the role of spatial planning in the reduction of wildfire hazard, given that the characteristics of fire hazard are distinctive from other natural hazards. Methods: Firstly, we used an online questionnaire answered by 175 municipalities of Portugal in order to examine local technicians' experience in applying spatial planning legislation and wildfire management policies. In a second step, we collected data from a Delphi survey with 27 experts with the aim of confirming or repudiating the importance of each need for integration between spatial planning and rural fire management indicated by the replies of the 175 municipalities. Key results, conclusions, and implications: One of the main identified weaknesses relates to the integration of the National Hazard Map in the Constraints Map of the Master Plans, considering the high inter-annual variability of fire hazard and the long-term definition of the municipal spatial planning framework. Focused on the Portuguese wildfire management approach, this paper contributes to bridging a critical gap in knowledge on the role of spatial planning in the reduction of wildfire hazard, given that the characteristics of fire hazard are distinctive from other natural hazards (e.g. floods, costal erosion, earthquakes). (This paper is part of a Special Issue that includes papers on research presented at the IX International Conference on Forest Fire Research, Coimbra, Portugal, November 2022.) [ABSTRACT FROM AUTHOR]

Background: Junction fires occur when two fire fronts merge. The rate of spread (ROS) and heat release rate (HRR) of the junction increase more quickly than that of each fire front, this effect exacerbated by slopes. Aims: Numerical modelling of junction fires and an interpretation of their behaviour are given examining the key influencing factors. Methods: Twenty physics-based simulations of laboratory-scale junction fires were performed for a shrub fuel bed using FIRESTAR3D, varying slope (0°–40°) and junction angles (15°–90°). Key results: Accelerative and decelerative behaviours were observed for junction angles lower than 45°, but above this, deceleration was absent. The behaviour was firmly related to junction angle evolution, which controlled the flame and interactions between fire fronts. HRR followed similar trends; maximum HRR increased with increasing junction angle. Convection was the primary heat transfer mode in the initial propagation phase. In no-slope cases, radiation was the dominant method of heat transfer, but convection dominated fires on slopes. Conclusions: The physics-based model provided great insight into junction fire behaviour. The junction angle was critical for determining ROS and fire behaviour. Implications: The research helped to assess the effects of some topographical parameters in extreme fires. Situational awareness, operational predictions and firefighter safety will consequently improve. An understanding of junction fire – the intersection of two fire fronts – was built by a parametric study for the main geometrical parameters (slope and junction angles) using physics-based model FIRESTAR3D. The study found correlations between these angles and the change in intensity and modes of fire. (This paper is part of a Special Issue that includes papers on research presented at the IX International Conference on Forest Fire Research, Coimbra, Portugal, November 2022.) [ABSTRACT FROM AUTHOR]

Background: In wildland–urban interface (WUI) fires, particulates from the combustion of both natural vegetative fuels and engineered cellulosic fuels may have deleterious effects on the environment. Aims: The research was conducted to investigate the morphology of the particulate samples generated from the combustion of oriented strand board (OSB). Findings were compared to the particulate samples collected from the combustion of noble-fir branches. Methods: The exposure conditions were varied to induce either smouldering combustion or flaming combustion of the specimens. Particulate samples were collected using thermophoretic sampling. Scanning electron microscopy (SEM) and subsequent image analysis were used to characterise particle sizes. Key results: The morphology of the generated particulates was influenced by the state of combustion for OSB as well as noble-fir branches. Conclusions: The combustion state resulted in differences in the particulate morphology for both OSB and noble-fir branches. More than 85% of the analysed particle diameters were less than 1000 nm in size collected from OSB specimens during smouldering combustion. Implications: The findings are the first step to better quantifying the morphology of particulates generated during WUI fire outbreaks. The experimental protocols and analysis methods presented may shed light on a problem that impacts human health in the WUI. In wildland–urban interface fires, particulates from combustion of natural vegetative and human-made fuels may have deleterious effects on the environment. Particulate samples were taken during both flaming combustion and smouldering combustion states. The morphology of the generated particulates is greatly influenced by the state of combustion for both fuels. (This paper is part of a Special Issue that includes papers on research presented at the IX International Conference on Forest Fire Research, Coimbra, Portugal, November 2022.) [ABSTRACT FROM AUTHOR]

Background: An increase in fire weather is expected in a warming climate, but its translation to fire activity (fire numbers and sizes) remains largely unknown. Additionally, disentangling the extent to which geographic and seasonal extensions as well as intensification contribute to future fire activity remain largely unknown. Aims: We aimed to assess the impact of future climate change on fire activity in southeastern France and estimate changes in spatial and seasonal distributions. Methods: We projected future fire activities using a Bayesian modelling framework combined with ensemble climate simulations. Changes in numbers of escaped fires (>1 ha), large fires (>100 ha) and burned area were studied for different emission scenarios or degrees of global warming. Key results: Fire activity could increase by up to +180% for +4°C of global warming, with large expansions of fire-prone regions and long seasonal lengthenings. Overall, changes will be dominated by intensification within the historical fire niche, representing two-thirds of additional future fire activity, half of this occurring during the high fire season. Conclusions: This study confirms that major changes in fire niches would be expected in Euro-Mediterranean regions. Implications: Long-term strategic policies for adapting prevention and suppression resources and ecosystems are needed to account for such changes. Projections of fire activity in southeastern France show that very large increases in fire metrics arise mostly from an intensification in the already fire-prone region during the core of the current fire season and only to a lower degree from an expansion of the fire-prone region and lengthening of the season. (This paper is part of a Special Issue that includes papers on research presented at the IX International Conference on Forest Fire Research, Coimbra, Portugal, November 2022.) [ABSTRACT FROM AUTHOR]

Background: Peatlands are becoming more vulnerable to smouldering fires, driven by climate change and human activities. Aims: This work explores the persistent burning, propagation, and emission of the deep peat fire. Methods: Laboratory experiments are conducted with a 1-m deep peat column, and smouldering fires are initiated at different depths. Key results: We found localised burning and multi-directional smouldering fire spread in deep peat layers. The smouldering temperature first decreases with depths up to −40 cm (from around 550 to 350°C) and then remains at about 300°C in the deeper layers. High moisture content can slow down in-depth fire propagation and reduce the burning duration. Conclusions: Peat fire can burn in deep layers for weeks, and its combustion is incomplete with small mass loss, because of a limited oxygen supply and low smouldering temperature. Measuring the carbon monoxide concentration near the surface can detect underground fire and monitor its intensity. Implications: This work helps reveal the underlying mechanism of the in-depth smouldering wildfires in peatland and supports future larger-scale peat fire experiments in the field. Smouldering fire in peatland is one of the largest wildfire phenomena on Earth that can burn slowly deep underground without flame. Laboratory experiments on tall peat soil samples revealed burning, propagation and emission physics of deep smouldering wildfires in peatland. (This paper is part of a Special Issue that includes papers on research presented at the IX International Conference on Forest Fire Research, Coimbra, Portugal, November 2022.) [ABSTRACT FROM AUTHOR]

Background: Understanding near-surface fire–atmosphere interactions at turbulence scale is fundamental for predicting fire spread behaviour. Aims: This study aims to investigate the fire–atmosphere interaction and the accompanying energy transport processes within the convective boundary layer. Methods: Three groups of large eddy simulations representing common ranges of convective boundary layer conditions and fire intensities were used to examine how ambient buoyancy-induced atmospheric turbulence impacts fire region energy transport. Key results: In a relatively weak convective boundary layer, the fire-induced buoyancy force could impose substantial changes to the near-surface atmospheric turbulence and cause an anticorrelation of the helicity between the ambient atmosphere and the fire-induced flow. Fire-induced impact became much smaller in a stronger convective environment, with ambient atmospheric flow maintaining coherent structures across the fire heating region. A high-efficiency heat transport zone above the fire line was found in all fire cases. The work also found counter-gradient transport zones of both momentum and heat in fire cases in the weak convective boundary layer group. Conclusions: We conclude that fire region energy transport can be affected by convective boundary layer conditions. Implications: Ambient atmospheric turbulence can impact fire behaviour through the energy transport process. The counter-gradient transport might also indicate the existence of strong buoyancy-induced mixing processes. Temperature perturbations resulting from solar heating of Earth's surface can induce buoyancy-driven wind turbulence. Using experimental numerical simulations, this work investigates how atmospheric wind turbulence, under different atmospheric conditions, can change the energy transfer within the fire area and subsequently impact fire behaviour. (This paper is part of a Special Issue that includes papers on research presented at the IX International Conference on Forest Fire Research, Coimbra, Portugal, November 2022.) [ABSTRACT FROM AUTHOR]

Background: Wildfires propagate through vegetation exhibiting complex spread patterns modulated by ambient atmospheric wind turbulence. Wind gusts at the fire-front extend and intensify flames causing direct convective heating towards unburnt fuels resulting in rapid acceleration of spread. Aims: To characterise ambient and fire turbulence over gorse shrub and explore how this contributes to fire behaviour. Methods: Six experimental burns were carried out in Rakaia, New Zealand under varying meteorological conditions. The ignition process ensured a fire-line propagating through dense gorse bush (1 m high). Two 30-m sonic anemometer towers measured turbulent wind velocity at six different levels above the ground. Visible imagery was captured by cameras mounted on uncrewed aerial vehicles at 200 m AGL. Key results: Using wavelet decomposition, we identified different turbulent time scales that varied between 1 and 128 s relative to height above vegetation. Quadrant analysis identified statistical distributions of atmospheric sweeps (downbursts of turbulence towards vegetation) with sustained events emanating from above the vegetation canopy and impinging at the surface with time scales up to 10 s. Conclusions: Image velocimetry enabled tracking of 'fire sweeps' and characterised for the first time their lifetime and dynamics in comparison with overlying atmospheric turbulent structures. Implications: This methodology can provide a comprehensive toolkit when investigating coupled atmosphere–fire interactions. Multi-modal observations of fire behaviour and overlying atmospheric turbulence were carried out for four wind-driven gorse bush experimental fires. Novel image velocimetry analysis outlined the dynamics and scales of motion of fire sweeps in relation to overlying atmospheric coherent turbulent structures. Results are useful for evaluating coupled fire–atmosphere model simulations. (This paper is part of a Special Issue that includes papers on research presented at the IX International Conference on Forest Fire Research, Coimbra, Portugal, November 2022.) [ABSTRACT FROM AUTHOR]

Background: Identifying if and how climatic and non-climatic factors drive local changes in fire regimes is, as in many other human-dominated landscapes, challenging in south-eastern France where both heterogeneous spatial patterns and complex fire trends are observed. Aim: We sought to identify the factors driving the spatial-temporal patterns of fire activity in southeastern France. Methods: We incorporated several non-climatic variables into the probabilistic Firelihood model of fire activity and implemented an enhanced spatio-temporal component to quantitatively assess remaining unexplained variations in fire activity. Key results: Several non-climatic drivers (i.e. orography, land cover and human activities) contributed as much as fire-weather to the distribution of fire occurrence (>1 ha) but less to larger fires (>10, 100 and 1000 ha). Over the past decades, increased fire-weather induced a strong increase in wildfire probabilities, which was actually observed on the western part of the region but not so in the east and Corsican Island, most likely due to reinforced suppression policies. Conclusions: While spatial patterns in fire activity are driven by land-use and land-cover factors, temporal patterns were mostly driven by changes in fire-weather and unexplained effects potentially related to suppression policies but with large differences between regions. We leveraged Bayesian spatio-temporal modelling to disentangle the contributions of climatic and non-climatic drivers for fire activity in Mediterranean France. We showed that recent fire-weather increase caused the increase of fire probability in the west; but in the east, it was over-compensated by a reduction of escaped-fire probability. (This paper is part of a Special Issue that includes papers on research presented at the IX International Conference on Forest Fire Research, Coimbra, Portugal, November 2022.) [ABSTRACT FROM AUTHOR]

Background: Mulching and burnt wood treatments are commonly applied to prevent the loss of soil quality and erosion, but their effect on soil multifunctionality remains unexplored. Aims: We filled this gap by assessing the medium-term (4 years) effects of these treatments on soil multifunctionality after a large wildfire in NW Spain. Methods: Straw mulching (SM) and cut plus lopping (CpL) treatments were applied in high-severity affected areas of heathland plant communities. CpL areas had been afforested with Scots pine 15 years before the fire. We considered four soil functions estimated in treated and burned control plots 4 years after fire: (1) carbon regulation; (2) water regulation; (3) soil fertility; and (4) nutrient cycling. The functions were integrated into a multifunctionality index and linear models were used to evaluate treatments effect. Key results: SM had no impact on individual functions and multifunctionality. Conversely, CpL with burnt Scots pine wood was able to sustain higher levels of multiple functions simultaneously than control areas. Consistent trade-offs between soil functions emerged in control areas for both treatments. Conclusions: Burnt wood could ensure long-lasting effects to promote soil multifunctionality in Mediterranean ecosystems. Implications: We recommend using a multifunctionality approach to avoid biases in treatment success. Post-fire treatment consisting of leaving burnt logs and felled branches in close contact with the forest floor promotes the ability of the soil to sustain high values of multiple functions simultaneously in the medium term after wildfire, as compared to straw mulching application. (This paper is part of a Special Issue that includes papers on research presented at the IX International Conference on Forest Fire Research, Coimbra, Portugal, November 2022.) [ABSTRACT FROM AUTHOR]

Background: Fire models use pyrolysis data from ground samples and environments that differ from wildland conditions. Two analytical methods successfully measured oxidative pyrolysis gases in wind tunnel and field fires: Fourier transform infrared (FTIR) spectroscopy and gas chromatography with flame-ionisation detector (GC-FID). Compositional data require appropriate statistical analysis. Aims: To determine if oxidative pyrolysis gas composition differed between analytical methods and locations (wind tunnel and field). Methods: Oxidative pyrolysis gas sample composition collected in wind tunnel and prescribed fires was determined by FTIR and GC/FID. Proportionality between gases was tested. Analytical method and location effects on composition were tested using permutational multivariate analysis of variance and the Kruskal–Wallis test. Key results: Gases proportional to each other were identified. The FTIR composition differed between locations. The subcomposition of common gases differed between analytical methods but not between locations. Relative amount of the primary fuel gases (CO, CH4) was not significantly affected by location. Conclusions: Composition of trace gases differed between the analytical methods; however, each method yielded a comparable description of the primary fuel gases. Implications: Both FTIR and GC/FID methods can be used to quantify primary pyrolysis fuel gases for physically-based fire models. Importance of the trace gases in combustion models remains to be determined. Oxidative pyrolysis gases were measured in a wind tunnel and small prescribed burns using two analytical methods. Gas composition measured by FTIR spectroscopy differed between wind tunnel and field fires. The relative amount of the primary fuel gases (CO, CH4) was not significantly affected by fire location. (This paper is part of a Special Issue that includes papers on research presented at the IX International Conference on Forest Fire Research, Coimbra, Portugal, November 2022.) [ABSTRACT FROM AUTHOR]

This article will, through the analysis of three parishes in Coimbra between the twelfth and the fourteenth century, investigate practices surrounding the commemoration of death. Through the study of extant wills, post-mortem donations, and necrological documents—such as Obituaries and Anniversary Books—this work seeks to describe the populations and communities who entrusted their final salvation to these churches. This characterization will allow a description of the typology of the suffrage ceremonies founded by these souls, meanwhile presenting an evaluation of the maintenance and management of these foundations by the churches and its chapters throughout the centuries. This paper intends to highlight what survives after death—not only in terms of memory, but also in light of social relationships, interpersonal and familial connections, and professional solidarities. Focusing on a population that is otherwise poorly documented—and moreover, represents a socio-professional background of a low echelon—this text intends to present a global characterization of the cult of the dead, with a further aim of drawing attention to the intervention and enrichment of parish pastoral care by the lay population in this Portuguese city. [ABSTRACT FROM AUTHOR]

The aim of this paper is to analyze the existence of cold-air pools on anticyclonic nights in a narrow urban valley where three hospital units and a road with intense traffic are located and where the slopes associated with proximity to a medium-size mountain introduce different factors from that observed in other valleys where this phenomenon forms on cold, calm nights. On these nights, it is observed that cold-air pools develop in the valley just after sunset, in opposition to the ridge that dominates the valley (thermal belts), and it is found that their formation, development, and disappearance after the first hours of the day is a daily phenomenon. Using fixed data loggers and portable data loggers on the surface and at altitude coupled to a UAV (drone), it was possible to calculate the variation of the air temperature (as well as to locate the inversion layer) in different sectors defined along the valley. The finding of temperature oscillation along the longitudinal profile and at altitude, reflects a double source of feeding: in-situ irradiation, and the air draining down the slopes of the massif. [ABSTRACT FROM AUTHOR]

The study of Early Modern Iberian footwear is taking its first steps. Both historiography and archaeological research have devoted little attention to this issue and organic remains found in excavation even tend to be discarded. This paper will address the results of DRESS project's questioning about courtly footwear, whose research benefited from a multidisciplinary team that included archaeologists familiar with the assemblages from which it was still possible to recover remains for analysis. The data provided and analysed starts with the study of the footwear evidence found in the Angra D shipwreck (Azores), a 16th century site. However, we soon noticed that this isolated study did not comprehensively provide information on the subject and two other intertidal archaeological sites were added: assemblages from Santa Clara-a-Velha (Poor Clares) Monastery in Coimbra (late 16th and 17th century), situated on the south bank of the Mondego River, and archaeological remains from the Campo das Cebolas (Old Market), on Lisbon waterfront (16th–17th century). Data from three archaeological sites were collected, drawn, and analysed, and a comparative methodology was applied. In the absence of syntheses for Iberian world, we used both critical bibliographies pertaining to North European collections and visual parallels, resulting on the first typological series of Iberian footwear. [ABSTRACT FROM AUTHOR]

The XIV Conference on Steel and Composite Construction was held in Coimbra, Portugal, organized by the Portuguese Association for Steel and Composite Construction. The conference aimed to showcase the latest innovations and achievements in steel construction and provided a platform for exchanging ideas and experiences among industry professionals, researchers, and educators. The conference featured 17 keynote lectures and 28 international papers from various countries. The book of proceedings contains 81 articles covering topics such as steel construction in the oil and mining industry, energy efficiency and sustainability of steel buildings, and structural safety and performance of new materials. The conference also awarded the best contributions, with the winning paper focusing on the expansion of The Berkeley Hotel in London. Participants had the opportunity to publish their articles in the digital journal ce/papers. [Extracted from the article]

The Coimbra concept of fractional order derivative is used to build a numerical approach using radial functions in this paper. The Coimbra derivative is capable of modelling a dynamic system with varying fractional order behaviour over time. The proposed scheme's stability and convergence are investigated. In one and two space dimensions, the developed approach is validated for the given model. By applying a periodic boundary condition on a bounded domain, the model's periodicity is shown statistically. The acquired findings demonstrate the new numerical scheme's potency and, as a result, its high order accuracy. [ABSTRACT FROM AUTHOR]

Digital location traces are a relevant source of insights into how citizens experience their cities. Previous works using call detail records (CDRs) tend to focus on modeling the spatial and temporal patterns of human mobility, not paying much attention to the semantics of places, thus failing to model and enhance the understanding of the motivations behind people's mobility. In this paper, we applied a methodology for identifying individual users' routine locations and propose an approach for attaching semantic meaning to these locations. Specifically, we used circular sectors that correspond to cellular antennas' signal areas. In those areas, we found that all contained points of interest (POIs), extracted their most important attributes (opening hours, check-ins, category) and incorporated them into the classification. We conducted experiments with real-world data from Coimbra, Portugal, and the initial experimental results demonstrate the effectiveness of the proposed methodology to infer activities in the user's routine areas. [ABSTRACT FROM AUTHOR]

Copyright of Vegueta: Anuario de la Facultad de Geografía e Historia is the property of Vegueta: Anuario de la Facultad de Geografia e Historia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper falls within the scope of heritage tourism studies, focusing particularly on one UNESCO World Heritage Site. It seeks to contribute to tourism literature by achieving a better understanding of which cognitive and affective factors are behind tourists' decisions to travel to these sites, their experiences during their visit and behavioural intention after the visit. A self-administered questionnaire focusing on the variables included in the proposed research model was given to tourists. A composite-based structural equation modelling approach was employed for the analysis. The findings revealed a significant and high correlation between travel attitude and perceived authenticity, travel motivations and destination image, and authenticity and destination image, but it goes beyond those relations by analyzing them in an integrated manner and at different stages of the visit to comprehend tourist behavioural intention after the visit. Besides the theoretical advancements with this study, the practical and managerial implications must be emphasized particularly for entities responsible for destination marketing that may be able to use the outcome of our research to work on proper promotion strategies. [ABSTRACT FROM AUTHOR]

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In the medical field, machine learning (ML) techniques are playing a significant and growing role because of their high potential in helping health practitioners make decisions and diagnosis. This inspective research aims to review ML models that may predict breast cancer in women and to compare their performances. A number of clinical features were measured among the 116 participants in the dataset of this study including insulin, glucose, resistin, adiponectin, homeostasis model assessment (HOMA), leptin, monocyte chemoattractant protein-1 (MCP-1), along with their age and body mass index (BMI). The researchers implemented 11 classification algorithms and their variations including Logistic Regression (LR), k-Nearest Neighbor (kNN), Support Vector Machine (SVM), Decision Tree (DT), Random Forest (RF), Gradient Boosting Method (GBM), and Naive Bayes (NB), in the detection of breast cancer on the publicly available Coimbra Breast Cancer Dataset (CBCD). Each classifier applies a unique hyper-parameter setting to perform prediction and their performances are compared in identifying breast cancer. As a conclusion of this study, Gradient Boosting (GB) machine learning algorithm is the best classifier in predicting breast cancer using the Coimbra Breast Cancer Dataset (CBCD) with an accuracy of 74.14%. k-Nearest Neighbor (kNN) classifier produces the fastest training time at 0.000598 seconds while Nonlinear Support Vector Machine (SVM) classifier gives with the fastest testing time at 0 seconds. Another conclusion of this paper is that the body mass index (BMI) is the top predictor, with 50% of the classifiers observing it as their top predictor and Glucose comes in second. This recommends that they may be a good pair of variables, which may predict breast cancer in women. [ABSTRACT FROM AUTHOR]

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This paper falls within the scope of cultural tourism studies, focusing on a World Heritage Site and intends to contribute to tourism literature by trying to better understand the differences between the tourists visiting it. A survey was conducted by self-administered questionnaires designed to identify different types of cultural tourists in post-UNESCO Coimbra (Portugal) so as to understand what they look for, the importance they assign to motivational factors, whether they are interested in participatory activities which call for cognitive, intellectual or affective engagement and their degree of satisfaction. A hierarchical cluster analysis was carried out based on age, education, family income, nationality, and length of stay. To perform this analysis of identification of homogeneous groups, Ward's method and the Squared Euclidean distance were used as a measure of similarity. The variables were standardized to avoid bias due to the different scales. The results of this analysis allowed the identification of two groups. Chi-square analyses and Mann-Whitney U tests were also carried out for better characterizing the clusters. Results seem to be useful for destination managers to provide what tourists seek, to enhance their experiences and satisfaction, and strengthen this destination competitiveness and value creation. [ABSTRACT FROM AUTHOR]

The purpose of the paper is to analyse the initiatives aimed at raising awareness of local communities on the importance of protecting and promoting distinct goods for sustainable food, culture, arts, and tourism, at EU level, to balance globalized food trends. The study carries out a comparative analysis at the level of three European Regions of Gastronomy: Coimbra Region, Sibiu Region and South Aegean Region. The key areas of the Region of Gastronomy Award program: raising citizen awareness about the food they eat, the value of local products and the need to innovate to protect local products. The benefits of such initiatives and their contribution to empowering local communities and to better quality of life were identified and highlighted. [ABSTRACT FROM AUTHOR]

This paper studies the music from the sixteenth century Coimbra manuscripts using both traditional musicological approaches and techniques based on statistical analysis and machine learning. A particular focus is placed on gaining insights into the origins of the anonymous and doubtfully attributed mass movements, looked at through the lens of potential stylistic differences between the Iberian and Franco-Flemish musical traditions of the time. Another goal is to explore the origins of the Coimbra works in the historical, political and social context of the reception of foreign repertoires. [ABSTRACT FROM AUTHOR]

Vitamin D3 (cholecalciferol) is a secosteroid and prohormone which is metabolized in various tissues to the biologically most active vitamin D hormone 1,25(OH)2D3 (calcitriol). 1,25(OH)2D3 has multiple pleiotropic effects, particularly within the immune system, and is increasingly utilized not only within prophylaxis, but also within therapy of various diseases. In this context, the latest research has revealed clinical benefits of high dose vitamin D3 therapy in autoimmune diseases. The necessity of high doses of vitamin D3 for treatment success can be explained by the concept of an acquired form of vitamin D resistance. Its etiology is based on the one hand on polymorphisms within genes affecting the vitamin D system, causing susceptibility towards developing low vitamin D responsiveness and autoimmune diseases; on the other hand it is based on a blockade of vitamin D receptor signaling, e.g. through pathogen infections. In this paper, we review observational and mechanistic evidence for the acquired vitamin D resistance hypothesis. We particularly focus on its clinical confirmation from our experience of treating multiple sclerosis patients with the so-called Coimbra protocol, in which daily doses up to 1000 I.U. vitamin D3 per kg body weight can be administered safely. Parathyroid hormone levels in serum thereby provide the key information for finding the right dose. We argue that acquired vitamin D resistance provides a plausible pathomechanism for the development of autoimmune diseases, which could be treated using high-dose vitamin D3 therapy. [ABSTRACT FROM AUTHOR]

Copyright of Documenta & Instrumenta is the property of Universidad Complutense de Madrid and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Information and Communication Technologies have been increasingly playing an essential role to support teaching and learning, especially in engineering courses, by taking advantage of online resources and online experiments. In particular, Wireless Sensor and Actuator Networks are simultaneously a subject of interest for several engineering courses and a way to enable remote access to laboratory experimental setups. The Remote and Virtual Laboratory of the Department of Informatics Engineering of the University of Coimbra (Portugal) is part of the flock.uc.pt web-based platform under development to allow users to perform remote and virtual experiments in several engineering domains. This paper aims to describe its potential use mainly in engineering courses and lifelong learning programs. The main characteristics of some remote experiments and the potential of Wireless Sensor and Actuator Networks to interact with laboratory systems are described. [ABSTRACT FROM AUTHOR]

This article seeks to answer a very concrete question: should .Military History be taught at university? It is, first and foremost, about contextualising the evolution of this field of studies in recent decades, in order to ascertain its scientific dignity. Then, based on the experience registered at three of the main Portuguese universities (especially in Coimbra) since the turn of the millennium, it seeks to present the most important arguments for the inclusion of Military History in the undergraduate curricula. Finally, this paper evokes a set of circumstances that, in Portugal but also in Spain, have made this area of teaching and research very appealing. [ABSTRACT FROM AUTHOR]

Earthquake resilience in historical centres is significantly affected by interactions between the built environment, defined as the network of building heritage and surrounding open spaces, and hosted population. Building vulnerability, earthquake-induced effects and population's exposure mainly influence the first emergency phases. In the immediate post-earthquake evacuation conditions, people should leave their position to gather in assembly points where first responders can rescue them. Thus, joint analyses of building damage and evacuation flows along the evacuation paths become essential to determine the risk levels for the urban scenario and to provide risk-mitigation solutions. This paper tries to reach this goal by adopting a holistic simulation-based approach. A simplified vulnerability assessment method is used to evaluate the seismic performance of masonry façade walls and to estimate debris depth on outdoor spaces. An existing earthquake pedestrians' evacuation simulator is used to evaluate the probable pedestrians' choices in such evacuation post-earthquake damage scenarios. Then, risk indexes, combining damage assessment and evacuation results, are provided to quantify evacuation safety and to outline critical conditions in the urban layout. Finally, the impact resulting from the consideration of a series of resilience-increasing strategies is simulated and discussed from the proposed risk indexes. A part of the historic centre of Coimbra, Portugal, one of the oldest and most relevant Portuguese cities, is used in this work as a pilot case study. Results show how the method could be used by Local Authorities and Civil Protection Bodies to outline, analyse and coordinate resilience-increasing strategies at the urban scale. [ABSTRACT FROM AUTHOR]

• Popular probabilistic solar forecasting methods are reviewed. • Various methods are compared using a standardized dataset at Folsom, California. • Forecasting methods with camera, satellite and NWP data are superior to the univariate ones. • With the provided data and code, the results shown here can be replicated and compared with ease. The present paper echos a recent data article, "A comprehensive dataset for the accelerated development and benchmarking of solar forecasting methods" [J. Renewable Sustainable Energy 11, 036102 (2019)]. The carefully composed dataset by Pedro, Larson, and Coimbra (PLC) presents a rare opportunity for solar forecasters to develop transparent and reproducible algorithms that can bring incremental contributions to the field. In their original paper, data from four different sources, namely, ground-based measurements, sky-camera images, satellite-imagery features, and numerical weather prediction outputs, were arranged in a machine-learning-ready setup. Subsequently, several benchmarks for deterministic forecasting were set forth, for intra-hour, intra-day, and day-ahead scenarios. Nonetheless, a weather forecast is intrinsically five-dimensional, spanning space, time, and probability. In this regard, five reference methods for probabilistic forecasting: (1) complete-history persistence ensemble, (2) Markov-chain mixture model, (3) ordinary least squares, (4) analog ensemble, and (5) quantile regression, are applied to the PLC dataset. The R code provided in this paper follows the structure of the original Python code precisely, facilitating those solar forecasters who are not familiar with Python but have a statistics background. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to demonstrate the relevance of developing literary tourism in Coimbra. Design/methodology/approach: This exploratory qualitative research identifies existent resources and development potential of literary tourism. The instruments of data collection were bibliographic research, questionnaires, interviews and participant observation. Findings: There are few literary tourism products in Coimbra, which contrasts with the number of literary places identified, namely, on the left bank of the River Mondego. Tourism development stakeholders in Coimbra have not paid enough attention to the emergence of literary tourism and the opportunities for the development of new sustainable cultural products related with it. Research limitations/implications: This study is limited by the size and continual renewal of the corpus, which implies a constant updating of data regarding authors and texts. Practical implications: This study will lead to the production of a database of Coimbra's literary resources and a digital literary map, allowing any citizen or entity to design and implement literary tourism products. Originality/value: To the best of authors' knowledge, this is the first study reviewing the potential of Coimbra as a literary tourism destination. Moreover, it discusses literary heritage as a source of products and experiences to foster more balanced tourist flows throughout the city. [ABSTRACT FROM AUTHOR]

Design and visual communication do not only work in digital universes. We are close to materials and there is a tangible heritage that is part of our global material culture. In the particular context of typography's culture and history, letterpress printing technique is nowadays a creative visualization and concept development tool that allows hands-on expression and comprising formal and physical details of type as "bodies" as well as specific constraints of graphic production. The following paper acknowledges the multidisciplinary role of media within the context of Anti-Amnesia, a design research project that seeks to sustain disappearing traditional industries and practices in Northern and Central Portugal. Among the initiative's core case studies is letterpress, namely Tipografia Damasceno, a well-known printing workshop based in Coimbra, Portugal, celebrating in 2019 its fifty years in active. However, due to modern day commercial challenges, Tipografia Damasceno is facing significant difficulties in terms of market/maker retention and viability, leading to a steady decline and an uncertain future beyond the current generation of active practitioners. Thereby, a wealth of traditional knowledge that is embedded in the material culture related with letterpress technique and creativity is at a risk of permanent loss. Correspondingly, project Anti-Amnesia intervenes by focusing on the recovery and restoration of related identities, traditions, and systems of knowledge: a mediation strategy that is based on the synthesis of several complementary media-centric courses of action, where design is the media tool that interfaces this semantic resolution for a restorative action. [ABSTRACT FROM AUTHOR]

A complete panorama of the analysis and evaluation for the energy indicator, the enhancement of the importance of this indicator when a sustainable assessment of existing neighborhoods is being done, and the introduction of a logical calculation process based on an index are the main contributions of this paper. Additionally, it is presented the implementation of this new approach into two case studies from the city of Coimbra, Portugal. The results of the energy assessments to the neighborhoods of Baixa and Alta yielded important data on the areas where these neighborhoods need to be improved. [ABSTRACT FROM AUTHOR]

Copyright of Revista Diálogos Mediterrânicos is the property of Nucleo de Estudos Mediterranicos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Since the development of the modern concept of chemical stabilisation of soils, geotechnical engineers have attempted to develop methodologies to describe the strength development based on a rational criterion, as in concrete technology, in which the binder content, the water content and/or the void ratio play an essential role. This paper presents a methodology to assess the unconfined compressive strength (UCS) in cement-based stabilised soft soils with a high water content (w > wL). A number of UCS tests were performed on cement-based stabilised Coimbra soft soil and the results obtained showed that the binder content and the liquidity index are fundamental parameters in assessment of the target strength. A simple and expedite method based on normalisation by the liquidity index is proposed. This method was successfully validated for a wide range of chemically stabilised soft soils, subjected to zero or small curing stresses, thus demonstrating its versatility. Applying the generalised relationship of the method, data from only one test condition are required to assess the UCS for other possible combinations of binder content and liquidity index. [ABSTRACT FROM AUTHOR]

Stereoscopic photography was one of the main forms of visual communication in the second half of the 19th century. The experience of viewing stereoscopic photographs using stereoscopes is described as evoking memories of the past, feelings of presence in the depicted scenes, but also fun and magical experiences. The fact that using these devices generates these impactful experiences is relevant for Cultural Heritage (CH) where we want visitors to have memorable experiences. Since classic stereoscopes are similar to contemporary smartphone-based Virtual Reality (VR) viewers, we questioned how the original viewing experience could be re-imagined to take advantage of current technologies. We have designed a new smartphone-based VR device—Spectare—targeted towards experiencing CH content (2D or 360° photos or videos, soundscapes, or other immersive content), while still maintaining a user experience close to the original. In this paper, we describe the design process and operation of the Spectare device. We also report on an usability evaluation with 20 participants and on the field testing where we applied the device to the visualization of CH content resulting from a digital reconstruction of the monastery of Santa Cruz in Coimbra, Portugal. The evaluations uncovered issues with the smartphone support piece of the device, but generally its usage was classified with a high usability score. Participants also classified the device as innovative, creative, impressive, fun. [ABSTRACT FROM AUTHOR]