Influence Of Topography Research Articles

UAV‐Lidar reveals that canopy structure mediates the influence of edge effects on forest diversity, function and microclimate

Abstract Widespread forest loss and fragmentation dramatically increases the proportion of forest areas located close to edges. Although detrimental, the precise extent and mechanisms by which edge proximity impacts remnant forests remain to be ascertained. By combining unmanned aerial vehicle laser scanning (UAV‐LS) with field data from 46 plots distributed at varying distances from the edge to the forest interior in a fragmented forest of New‐Caledonia, we investigated edge influence on forest structure, composition, function, above‐ground biomass (AGB) and microclimate. Using simple linear regressions, structural equation modelling and variance partitioning, we analysed the direct and indirect relationships between distance to edge, UAV‐LS‐derived canopy structural metrics, understorey microclimate, AGB, taxonomic and functional composition while accounting for the potential influence of fine‐scale variation in topography. We found that the distance to the closest forest edge was strongly correlated with canopy structure and that canopy structure was better correlated to forest composition, function, biomass and microclimate than distance to the closest forest edge. This suggests that the influence of edge is mediated by changes in canopy structure. Plots located near the edge exhibited a lower canopy with more gaps, higher microclimate extremes, lower biomass, lower taxonomic and functional diversity as well as denser wood and lower specific leaf area. UAV‐LS‐derived canopy structural metrics were relevant predictors of understorey microclimate, biomass and taxonomic and functional composition. Overall, the influence of topography was marginal compared to edge effects. Synthesis. Accounting for fine‐scale variation in canopy structure captured by UAV‐LS provides insights on the multiple edge impacts on key forest properties related to structure, diversity, function, biomass and microenvironmental conditions. Integrating UAV‐LS‐derived data can foster our understanding of cascading and interacting impacts of anthropogenic influence on tropical forest ecosystems and should help to improve conservation strategies and landscape management policies.

Population Genetic Analysis of Six Chinese Indigenous Pig Meta-Populations Based on Geographically Isolated Regions.

The diversification of indigenous pig breeds in China has resulted from multiple climate, topographic, and human cultural influences. The numerous indigenous pig breeds can be geographically divided into six meta-populations; however, their genetic relationships, contributions to genetic diversity, and genetic signatures remain unclear. Whole-genome SNP data for 613 indigenous pigs from the six Chinese meta-populations were obtained and analyzed. Population genetic analyses confirmed significant genetic differentiation and a moderate mixture among the Chinese indigenous pig meta-populations. The North China (NC) meta-population had the largest contribution to genetic and allelic diversity. Evidence from selective sweep signatures revealed that genes related to fat deposition and heat stress response (EPAS1, NFE2L2, VPS13A, SPRY1, PLA2G4A, and UBE3D) were potentially involved in adaptations to cold and heat. These findings from population genetic analyses provide a better understanding of indigenous pig characteristics in different environments and a theoretical basis for future work on the conservation and breeding of Chinese indigenous pigs.

The role of topography in landform development at an active temperate glacier in Arctic Norway

AbstractTopography exerts a strong control on how glaciers respond to changes in climate. Increased understanding of this role is important for both refining model predictions of future rates of glacier recession and for reconstructing climatic change from the glacial geological record. In this paper, we examine the geomorphological and sedimentological evidence in the foreland of Fingerbreen, a temperate outlet of the plateau icefield Østre Svartisen. The aim is to investigate the relationship between processes of landform generation and the changing influence of topography as recession progressed. The Fingerbreen foreland is dominated by bouldery Little Ice Age moraines and extensive areas of striated bedrock. A heavily fluted zone occurs in the central part of the foreland that is cross‐cut by annual transverse and sawtooth moraines. Systematic investigations of the structural architecture of moraines at various locations in the foreland provide evidence for a range of moraine‐forming processes, which can be linked to the topographic setting (e.g. deposition on a reverse bedrock slope) and drainage conditions. This includes push and bulldozing of proglacial sediments and squeezing of sub‐glacial sediments and submarginal freeze‐on of sediment slabs. We also identify variations in moraine spacing as a result of topography. This research demonstrates the importance of topography when interpreting moraine records in the context of climate and glacier dynamics.

The Densification Characteristics of Polished Fused Silica Glass and Its Scattering Characteristics

Optical surface scattering is an important subject in the field of optics. Previous studies of surface scattering mainly focused on the influence of surface topography and often ignored the influence of the mechanical property’s change caused by polished surface densification. In this paper, we study the mechanical property of fused silica glass in detail and analyze the scattering behaviour of actual fused silica glass’s surface with sub-angstrom roughness, considering the topography and the change of refractive index. Experimental results show that there is a negative correlation between the height and modulus on the surface of roughly polished fused silica glass, and the correlation coefficient γ = −0.29 was determined. After super−polishing, the mechanical properties of the sample surface become significantly uniform with a roughness of Rq = 0.06 nm and Ra = 0.05 nm, and the correlation coefficient becomes γ = −0.02. Moreover, the nanoindentation test proves that silica glass surfaces have been densified during polishing. Based on the densification characteristics, the bidirectional reflectance distribution function (BRDF) was simulated by the finite element method. The result indicates that the densification characteristics will increase the scattering intensity. This work not only deepens the understanding of the properties of polished optical surfaces but also the surface scattering characteristics of optical elements.

Radiometric Correction with Topography Influence of Multispectral Imagery Obtained from Unmanned Aerial Vehicles

This article aims to present the methods of the radiometric correction of multispectral images—a short review of the existing techniques. The role of radiometric correction is essential to many applications, especially in precision farming, forestry, and climate analysis. Moreover, this paper presents a new relative approach, which considers the angle of inclination of the terrain and the angle of incidence of electromagnetic radiation on the imaged objects when obtaining the baseline data. This method was developed for data obtained from low altitudes—for imagery data acquired by sensors mounted on UAV platforms. The paper analyses the effect of the correction on the spectral information, i.e., the compatibility of the spectral reflection characteristics obtained from the image with the spectral reflection characteristics obtained in the field. The developed method of correction for multispectral data obtained from low altitudes allows for the mapping of spectral reflection characteristics to an extent that allows for the classification of terrestrial coverage with an accuracy of over 95%. In addition, it is possible to distinguish objects that are very similar in terms of spectral reflection characteristics. This research presents a new method of correction of each spectral channel obtained by the multispectral camera, increasing the accuracy of the results obtained, e.g., based on SAM coefficients or correlations, but also when distinguishing land cover types during classification. The results are characterized by high accuracy (over 94% in classification).

Optimization of a multi-fractured multilateral well network in advantageous structural positions of ultralow-permeability hydrate reservoirs

In this study, we propose a production enhancement strategy that combines multiplanar fractures with a multilateral well network, namely multi-fractured multilateral well network (MMWN), to improve the production efficiency of ultralow-permeability hydrate reservoirs (ULPHs). Considering that natural gas hydrate is generally disseminated in nonhorizontal strata, the influence of topography on the productivity of multilateral wells was first revealed, and then the stimulation effects of MMWN with different geometries and properties in advantageous structural positions of ULPHs on gas production were systematically analyzed. Results indicate that gas extraction from multilateral wells is good at the structural low of ULPHs. MMWN significantly increased the stimulated reservoir volume, leading to an increase in gas production by more than 23 times compared to using the depressurization method alone. Using the MMWN did not require extra energy and caused no ice formation. Improving the planar fracture number, area, width, and permeability effectively facilitated gas recovery. Enlarged fracture spacing is suitable for long-term production. Gas production is not influenced by porosity, overlarge width, or high permeability (over 10 D) of planar fractures. This novel study suggests that the combination of multilateral well networks and highly intensive reconstruction is an effective method to produce gas hydrates.

Insights in Hailstorm Dynamics through Polarimetric High-Resolution X-Band and Operational C-Band Radar: A Case Study for Vienna, Austria

Abstract Data from a dual-polarized, solid-state X-band radar and an operational C-band weather radar are used for high-resolution analyses of two hailstorms in the Vienna, Austria, region. The combination of both radars provides rapid-update (1 min) polarimetric data paired with wind field data of a dual-Doppler analysis. This is the first time that such an advanced setup is used to examine severe storm dynamics at the eastern Alpine fringe, where the influence of local topography is particularly challenging for thunderstorm prediction. We investigate two storms transitioning from the pre-Alps into the Vienna basin with different characteristics: 1) A rapidly evolving multicell storm producing large hail (5 cm), with observations of an intense ZDR column preceding hail formation and the rapid development of multiple pulses of hail; and 2) a cold pool–driven squall line with small hail, for which we find that the updraft location inhibited the formation of larger hailstones. For both cases, we analyzed the evolution of different ZDR column metrics as well as updraft speed and size and found that (i) the 90th percentile of ZDR within the ZDR column was highest for the cell later producing large hail, (ii) the peak 90th percentile of ZDR preceded large hailfall by 20 min and highest updraft size and speed by 10 min, and (iii) sudden drops of the 90th percentile of ZH within the ZDR column indicated imminent hailfall. Significance Statement Thunderstorm evolution on the transition from complex terrain into the Vienna basin in northeastern Austria varies strongly. In some instances, thunderstorm cells intensify once they reach flat terrain, while in most cases there is a weakening tendency. To improve our process understanding and short-term forecasting methods, we analyze two representative cases of hail-bearing storms transitioning into the Vienna basin. We mainly build our study on data from a new, cost-efficient weather radar, complemented by an operational radar, lightning observations, and ground reports. Our results show which radar variables could be well suited for early detection of intensification, and how they relate to thunderstorm updraft speeds and lightning activity.

Spatial-Temporal Variations of Extreme Precipitation Indices in the Xinjiang Cold Area over the Past 60 Years

The damage of extreme precipitation to the social economy and ecological environment has attracted extensive attention. Daily precipitation data of 59 meteorological stations located in Xinjiang Uygur Autonomous Region were selected, where the temporal and spatial distribution and variation characteristics of extreme precipitation from 1961 to 2017 were comprehensively analyzed by percentile threshold method, precipitation tendency rate method, the trend-free pre-whitening Mann Kendall trend test, Mann Kendall mutation test, and other methods. Further, three methods, the continuous wavelet transform, cross wavelet transform, and wavelet coherence analysis, were selected to analyze the correlation between extreme precipitation index and six atmospheric circulation indexes. Results show that from 1961 to 2017, the precipitation in Xinjiang increased, and the extreme precipitation (R99P), extreme precipitation days (R99D), extreme precipitation contribution rate (R99C), and extreme precipitation intensity (R99I) showed a significantly increasing trend. Due to the influence of topography, the spatial distribution of extreme precipitation is bounded by the Tianshan Mountains, decreasing from northwest to southeast, meeting the characteristics of “Northern Xinjiang is greater than Southern Xinjiang,” indicating obvious spatial heterogeneity. Among the selected atmospheric circulation indexes, Western Pacific Subtropical High Intensity Index (WPSHII) and Western Pacific Subtropical High Intensity Index (SCSSHII) contribute significantly to extreme precipitation events in Xinjiang. There is an obvious positive correlation between SCSSHII and extreme precipitation index. In other words, the greater the SCSSHII, the greater the frequency and frequency of extreme precipitation events in the study area, and the more prone it is to natural disasters such as rainstorms and floods.

Influence of topography on the optical performances of a Fresnel linear asymmetrical concentrator array: The case of the eLLO solar power plant

Solar field orientation and inclination are variables that significantly influence the optical performance over the year of Linear Fresnel Collector (LFC). The usual field configuration is a flat north-south (NS) orientation, however, the future development of the LFC sector, for example for solar heat for industry, could more often impose the land choice and therefore the solar field configuration. To study the influence of such configuration on a solar field optical performance, a ray-tracing model was used to evaluate the LFC optical performance for each solar position and a consistent methodology was developed to evaluate the solar position in the module reference system. This method allows studying the optical performance of any LFC array configuration. The paper first looks separately at the influence of orientation and tilt imposed by the topography of the eLLO project, then focuses on the eLLO solar power plant case study. The results of eLLO's solar line simulation showed an increase of 1.6% in annual absorbed energy compared to NS implementation, which is the best orientation for the localization. In conclusion, the design and implementation of modular LFC array can be adapted to a wide range of terrains and can even take advantage of this constraint.

Linking process to pattern in community assembly in dry evergreen Afromontane forest of Hararghe highland, Southeast Ethiopia

Abstract
 
 Many scholars have attempted to identify the role of deterministic and stochastic processes in community assembly, but there is no consensus on which processes dominate and at what spatial scales they occur. To shed light on this issue, we tested two non-exclusive processes, scale-dependent hypotheses: (i) that limiting similarity dominates on small spatial scales; and (ii) that environmental filtering does so on a large scale. To achieve this, we studied the functional patterns of dry evergreen Afromontane forest communities along elevation gradients in southeastern Ethiopia using floristic and functional trait data from fifty-four 0.04 ha plots. We found evidence of functional overdispersion on small spatial scales, and functional clustering on large spatial scales. The observed clustering pattern, consistent with an environmental filtering process, was most evident when environmental differences between a pair of plots were maximized. To strengthen the link between the observed community functioning pattern and the underlying process of environmental filtering, we demonstrated differences in the topographical factors of the most abundant species found at lower and higher elevations and examined whether their abundance varied over time or changed with time along the elevation. We found (i) that the largest functional differences in the community (observed between lower and upper dry evergreen Afromontane forest assemblages) were primarily the result of strong topographical influence; and (ii) that the abundance of such species varied along the elevation gradient. Variation in stand structure and tree species diversity within the DAF plots shows that topography is among the important drivers of local species distribution and hence the maintenance of tree diversity in dry Afromontane forest.
 Our results support the conclusion that environmental filtering at large spatial scales is the primary mechanism for community merging, since functional grouping pattern was associated with species similarities in topographic variation, ultimately leading to changes in species abundances along the gradient. There was also evidence of competitive exclusion at more homogeneous and smaller spatial scales, where plant species compete effectively for resources.

Simulating glacier mass balance and its contribution to runoff in Northern Sweden

Glaciers are one of the main sources of freshwater in cold regions. The glacier melting process can significantly impact the glacier mass balance (GMB) and contribute a large amount of runoff in cold regions. This study applied the recently developed semi-distributed glacio-hydrological conceptual model (FLEXG) to understand the glacier melting process and the effect of topography on GMB in the Torne River basin, northern Sweden. The study simulated glacier and snow accumulation and ablation, as well as runoff from the glacier and non-glacier areas of the basin using the FLEXG model for the time period 1989–2018. The FLEXG model considers the influence of topography on runoff generation, and in this study the basin was classified into 143 zones depending on elevation and aspect. In order to gain a comprehensive view of the performance of the FLEXG model, the classical lumped hydrological model HBV was used and compared with the FLEXG model in simulating total streamflow and peak runoff at the outlet of the basin. Our results revealed that the FLEXG model performed well in reproducing the streamflow (also better than the HBV model) with metric Kling-Gupta Efficiency (KGE) of 0.80 and 0.71 for the calibration and validation periods, respectively. We also found that the FLEXG model performs better in peak runoff simulation than the HBV model. The FLEXG simulated snow cover area proportion agreed well with the MODIS satellite snow cover product (R2 = 0.60 and RMSE = 28%). The GMB in different elevation zones was simulated, and a downward trend was found for GMB changes during the study period because of climate change.

Evaluation of regression models' accuracy for estimating soil heavy metals content from topographic rectified satellite imagery (Case study: Irankouh from Iran)

Although the traditional approach is vital in environmental studies, satellite images have recently become one of the main tools for estimating soil pollution due to their advantages. Among sources of soil pollution, heavy metals (HMs) play a crucial role; in this regard, evaluating the soil contamination anomaly is indispensable due to an enormous number of HMs mines and agricultural land irrigation by industrial sewage in developing countries. Therefore, the main goals of this study are: to evaluate Landsat-8 image capability for estimating HMs content (Cr, Cd, Co, and AS) of the soil, performance evaluation of linear and nonlinear regression models, and topographic influence on the estimation accuracy of heavy metals. To do so, we applied multivariate-linear, partial least square, exponential regression, and neural network models to achieve a relation between the HMs content and soil spectral reflectance. Regarding the R2 value of models, the neural network demonstrated a more acceptable performance than other models. The results show that topographic correction improves the accuracy of HMs estimation; for example, the Minnaert model obtained the highest score (equal to 30.02), which is sufficient to support the preceding sentence. Furthermore, the neural network and Minnaert (with a score of 17.56) would produce the best results for estimating HMs content.

행정 경계지역에서의 지역주의 투표 행태

This paper examines the regionalist voting behavior in the geographically adjacent Yeongnam-Honam border area, although the administrative districts at the metropolitan level are different. More specifically, this study aims to empirically verify the regionalist voting relaxation phenomenon in the Yeongnam-Honam border area, where emotional communication is possible through daily life sharing and various friendly exchanges. To do so, collective data are examined with counting data for each voting district for presidential and general elections held in Korea since 2000, and voter support patterns of regional dominant parties in the region are analyzed. As a result of the analysis of the collective data, First of all, it was possible to verify the regionalist voting relaxation phenomenon withdrawing from support for regional dominant parties in 15 of the 26 Eups and Myeons as the subject of analysis of the Yeongnam-Honam border area belonging to 9 Sis and Guns. Through this, it was validated that “Honam in Yeongnam, Yeongnam in Honam” actually exists. However, it was analyzed that this regionallist voting relaxation phenomenon did not affect between neighboring Eups and Myeons. Second of all, it was confirmed that the possibility that various friendly affairs and geographical or topographical influences could affect regionalist voting behavior. The intensity of relaxation phenomenon was strong in which exchanges such as sisterhood relationships and friendly activities between neighboring Eups and Myeons were held, or in areas without topographical obstacles such as mountains and rivers.

Estimation of surface soil moisture by combining a structural equation model and an artificial neural network (SEM-ANN)

Soil moisture is an important variable of the environment that directly affects hydrological, ecological, and climatic processes. However, owing to the influence of soil type, soil structure, topography, vegetation, and human activities, the distribution of soil water content is spatially heterogeneous. It is difficult to accurately monitor the distribution of soil moisture over large areas. To investigate the direct or indirect influence of various factors on soil moisture and obtain accurate soil moisture inversion results, we used structural equation models (SEMs) to determine the structural relationships between these factors and the degree of their influence on soil moisture. These models were subsequently transformed into the topology of artificial neural networks (ANN). Finally, a structural equation model coupled with an artificial neural network was constructed (SEM-ANN) for soil moisture inversion. The results showed the following: (1) The most important predictor of the spatial variability of soil moisture in the April was the temperature–vegetation dryness index, while land surface temperature was the most important predictor in the August; (2) After the ANN model was improved, the inversion accuracy of surface soil moisture by SEM-ANN model was improved, and the R2 of verification set was increased by 0.01 and 0.02 in April and August, respectively, and the relative analysis error was reduced by 0.5 % and 1.13 %. (3) There were no significant differences in soil moisture distribution trends between the April and August.

Evaluating the impact of topography on the initiation of Nor’westers over eastern India

Pre-monsoon thunderstorms are catastrophic and frequent over eastern and north-eastern India. The Chhota Nagpur plateau (CNP) believes to be the triggering platform for thunderstorms over east India. This study attempted to determine the influence of the CNP topography on thunderstorm formation and propagation by observing the changes in the values of thermodynamic indices over eastern India. The work attempted ten cases of thunderstorms in multiple simulations, i.e. each case simulated three times with varying elevations of CNP topography (in total 30 simulations) by Advanced Weather Research and Forecasting (WRF–ARW) model. Our analysis revealed that when the elevation of topography of the CNP changes (increases/decreases), the characteristics of several thermodynamic indices alter considerably (with values changing from negative to the positive side for some indices). We found the Cross Total Index (CTI) shows considerable differences in all the thunderstorm simulations, and the values are higher in the increased CNP topography (∼ −4 to 6 °C). However, the Humidity Index (HI) (∼ −10 to 15 °C) and Convective INhibition (CIN) (∼ −200 to 200 J/Kg) values depict considerable changes in decreased topography. The results are crucial to understanding and quantifying the role of CNP in pre-monsoon thunderstorms over east India.

Analytical computation of total topographic torque at the core–mantle boundary and its impact on tidally driven length-of-day variations

SUMMARYThe Earth’s rotation exhibits periodic variations as a result of gravitational torques exerted by the Sun and the Moon and of angular momentum exchange of the solid Earth with the Earth’s atmosphere and hydrosphere. Here, we aim at determining the complementary effect of the deep interior on variations in the length-of-day (LOD) and focus on the influence of topography at the core–mantle boundary (CMB). For this purpose, we have developed an analytical approach for solving the Navier–Stokes equation for global rotational motions and inertial waves, based on and extending the approach of Wu & Wahr (1997). An advantage of the analytical approach is that it allows to identify the frequencies and topographic spherical harmonics degrees and orders where resonance can happen, as well as to quantify the total amplifications in the tidal effects on LOD variations. Although the resonances are found to be sometimes quite near tidal frequencies, we show that they are not sufficiently close to induce significant perturbations in LOD variations, except for two of the tides, the fortnightly and monthly tides Mf and Mm. Our results go beyond the findings of Wu & Wahr (1997), extending them to a much wider range of degrees and orders of topographic coefficients. We show that there is an amplification in Mf and Mm induced by the degree 18-order 10 and by the degree 7-order 1 of the topography, respectively. Our approach is generic in the sense that it can be applied to other orientation changes of the Earth as well as to other planets.

Response of remote water vapor transport to large topographic effects and the multi-scale system during the “7.20” rainstorm event in Henan Province, China

A high-resolution numerical simulation was carried out for the extremely heavy rainfall in Henan Province caused by the remote water vapor transport of the binary typhoons In-fa and Cempaka on 20 July 2021. The control simulation successfully captured the evolution process and spatial distribution of the rainfall. The key water vapor supply area of the event was a triangle moisture transport influence domain formed by the local low vortex and the multi-vapor vortex system at low-latitude. By separating the effects of multiple tropical cyclones one by one, we found that In-fa dominated the main water vapor transport in the meridional direction, and directly affected the local water vapor supply in this rainfall process. Cempaka affected intermediate moisture transfer and impacted the location of precipitations, by regulating the distribution of water vapor input and output in the meridional and zonal directions. Removing Cempaka, In-fa, and binary typhoons can reduce the rainstorm area by about 7%, 65%, and 86%, respectively. These differences underscore the importance of binary typhoons in transforming a normal heavy rain event into a high-impact, record-breaking rain event. In addition, the Qinghai-Tibet Plateau exerts a modulation effect on the remote moisture transport of typhoons by multi-scale interactions. Eliminating the influence of plateau topography weakens the maximum precipitation by about 30% and the distribution of heavy rain by about 62%. After comprehensive diagnosis, a conceptual model of typhoon remote water vapor transport based on moisture multi-vortex structure under multi-scale interactions is proposed. The extremity and uncertainty of this rainstorm event can be attributed to the maintenance and development of binary typhoons, the northward extension of the subtropical high, and the anomalous convergence mechanism of water vapor due to the large terrain blocking effect on the plateau.

Study on mountain Confucian temple spatial layout and landscape environment: an analytical study of Confucian temples in Southwest China during the 15th-19th centuries

ABSTRACT Taking Confucian temples in Southwest China as an example, this paper discusses the combination of traditional temple architecture in East Asia and mountain topography. Based on the fieldwork survey of 14 existing mountain Confucian temples in Southwest China, the paper provides the first systematic examination of the topographical influences on courtyard spatial layouts and landscape environment of Confucian Temple. The author discusses the topographical influences on the orientation and axis sequence organization of the Confucian temple. Then, the diversity of the guiding space layouts is explored by combining the theory of Figure-ground and Space Syntax. On this basis, the author takes the most representative “vertical interface” of the mountain Confucian temple as a point of departure for re-examining the plant configuration and water environment that match the mountain topography. The finding of the paper shows how to implement a set of mature building complex under mountain topography and create an amazing landscape environment in Southwest China during the 15th- 19th centuries. The work enriches the discourse in the study of the traditional temple in East Asia and provides the theoretical basis for the conservation of Confucian temple architectural heritage.

Monitoring and alarm method for wildfires near transmission lines with multi‐Doppler weather radars

AbstractMonitoring and alarm play an important role in preventing trip‐out caused by wildfires for high‐voltage transmission lines. This paper proposes a multi‐Doppler weather radar‐based method for monitoring and alerting of wildfires near transmission lines. Firstly, characteristic parameters are mathematically proposed to distinguish wildfire's radar echoes. Then, the four‐site neighbourhood algorithm and the multithreading method are used to extract all possible wildfire echo units detected by various Doppler weather radars, and a cumulative probability is calculated to identify the wildfire. Finally, a regional block search method is used to quickly locate wildfire‐affected transmission towers. The membership function of spread time in the fuzzy set is proposed to determine the alarm level, which takes into account the influences of environment, topography, and vegetation on wildfire spread rate. The application to a provincial power grid demonstrates that the proposed method has an accuracy of 82.4%, a missing alarm rate of 27.4%, and a delay of fewer than 15 min. In addition, the joint observation of wildfires by multi‐Doppler weather radars and satellites indicates a promising application prospect for transmission line wildfire fighting.

Disentangling the drivers of continental mammalian endemism.

Endemic species and species with small ranges are ecologically and evolutionarily distinct and are vulnerable to extinction. Determining which abiotic and biotic factors structure patterns of endemism on continents can advance our understanding of global biogeographic processes, but spatial patterns of mammalian endemism have not yet been effectively predicted and reconstructed. Using novel null model techniques, we reconstruct trends in mammalian endemism and describe the isolated and combined effects of physiographic, ecological, and evolutionary factors on endemism. We calculated weighted endemism for global continental ecoregions and compared the spatial distribution of endemism to niche-based, geographic null models of endemism. These null models distribute species randomly across continents, simulating their range sizes from their degree of climatic specialization. They isolate the effects of physiography (topography and climate) and species richness on endemism. We then ran linear and structural models to determine how topography and historical climate stability influence endemism. The highest rates of mammalian endemism were found in topographically rough, climatically stable ecoregions with many species. The null model that isolated physiography did not closely approximate the observed distribution of endemism (r2 =.09), whereas the null model that incorporated both physiography and species richness did (r2 =.59). The linear models demonstrate that topography and climatic stability both influenced endemism values, but that average climatic niche breadth was not highly correlated with endemism. Climate stability and topography both influence weighted endemism in mammals, but the spatial distribution of mammalian endemism is driven by a combination of physiography and species richness. Despite its relationship to individual range size, average climate niche breadth has only a weak influence on endemism. The results highlight the importance of historical biogeographic processes (e.g. centers of speciation) and geography in driving endemism patterns, and disentangle the mechanisms structuring species ranges worldwide.