Heterogeneous Terrain Research Articles

Potential and challenges of wind measurements using met-masts in complex topography for bridge design: Part II – Spectral flow characteristics

This study quantifies the influence of the local topography on sonic anemometer measurements mounted on tall met-masts deployed in Norwegian fjords. This assessment is done by analysing the second-order structure of turbulence in the frequency space. The objective is to evaluate how the data collected by these masts can help with the design of future fjord-crossing bridges. Using measurements from eight masts deployed in three different fjords, spectral characteristics common to the different locations were identified. Among the characteristics investigated, the one-point velocity spectra and the vertical coherence of turbulence are of special interest for bridge design. Using only situations with a mean wind speed of 12 ​m ​s−1 and above and rather stationary flow conditions, the remaining wind direction sectors could be classified into two main groups: those with a long fetch over smooth topography and those with a rough heterogeneous terrain upstream of the masts. It was found that if the velocity spectra are normalized by an appropriate estimate of the friction velocity, surface-layer scaling may be applicable in Norwegian fjords, at least under near-neutral conditions. The velocity spectra, estimated with long upstream fjord fetches have characteristics consistent with those collected in coastal and offshore environments. The Davenport model showed limited capabilities in describing the co-coherence of turbulence on vertical separations. The dependency of the Davenport decay coefficient with the height and spatial separation is highlighted and may be substantial in mountainous terrain. Although the spectral flow characteristics estimated on the shore of fjords are relevant for the design of fjord-crossing bridge towers, they may not easily be extrapolated for the modelling of the turbulent flow in the middle of the fjord. Nevertheless, they are still valuable to complement computational fluid dynamic simulations, wind tunnel tests, or remote sensing of wind across the fjord.

Quantifying spatio-temporal variations of evapotranspiration over a heterogeneous terrain in the Arid regions of Northwestern China.

ABSTRACT Evapotranspiration (ET) is a major component of water and energy budgets in terrestrial ecosystems and quantifying ET over a heterogeneous land surface is of extraordinary significance. However, previous studies on the spatial distribution of daily ET in the middle Hexi corridors were mostly temporal discontinuous, and thus hinder the applications in agriculture and meteorology. Based on Land Remote-Sensing Satellite (Landsat) 8 Operational Land Imager (OLI) and Thermal Infrared Sensor (TIRS) data and the Surface Energy Balance System (SEBS) model, surface ET in 2014 were estimated over a desert oasis with heterogeneous land cover in the middle Hexi corridors of the arid regions in northwestern China. Daily ET was derived from the reference crop ET which was based on the relationship between actual ET and potential ET. The main results indicated that (1) the estimated daily ET values agreed well with the Eddy Covariance (EC) measurements for cropland (The coefficient of determination (R 2) = 0.96, p < 0.05, Root Mean Square Error (RMSE) = 1.32 mm day−1, Mean Absolute Error (MAE) = 1.11 mm day−1). Daily ET was more than 2.5 mm day−1 from June to July in 2014. (2) Seasonal ET was the largest in the summer (190.55 mm), followed by spring (100.03 mm), autumn (62.27 mm), and winter (6.83 mm). (3) ET from the waterbody was the highest, followed by ET from cropland, shelterbelt, bare land, and shrubland, suggesting that ET was mainly controlled by the water availability of the underlying surface. Multiple land-cover types showed similar variations in a year, but the seasonal variations were different. This study provides a foundational understanding of the patterns of water and heat exchange over heterogeneous regions, which can be helpful to make local policy in rational water management and land resource utilization.

Faster transport through slower runs: ant relocation dynamics in nature

Recruitment is a fundamental feature of animal societies and its efficiency largely depends on within-group communication. Insect societies are often populous and decentralised decisions need to be made by individuals with limited local information when time is of the essence. Recruitment of colony members to food, defence or to a new nest fall under this category. Colony relocation in tandem running ants is a particularly important case where only a small number of leaders possess information about the new nest and time is crucial, as longer exposure is detrimental to the colony’s survival and reproduction. We investigated the programmes and positional effects of individual members during relocation of the Indian tropical ant Diacamma indicum in their natural habitat. Analysis of more than 1000 transports across eight relocating colonies reveals that they have a path efficiency of 85%. We found that transporters reoriented towards the target nest within seconds of initiation and tandem running in this species is so well organised that over 97% of transports reached their target nest without facing any interruption indicating that the communication between leaders and followers was exceptional. With an average speed of 3.8 cm per second these are the fastest tandem running ants recorded. We used mixed-effects model to understand the effect of patch heterogeneity and transport type on the speed and path efficiency of these ants and found that tandem leaders reduced their speed when traversing grassy patches and relied upon the slower coupled adult-brood transport. This investigation of ants performing tandem runs through heterogeneous terrains showcases the exceptionally efficient recruitment dynamics during colony relocation. In the next step, similar studies in the context of foraging and guarding in the natural habitat will be required to fully appreciate the recruitment capabilities of these superorganisms.

Numerical modelling of the water surface movement with macroscopic particles of dam break flow for various obstacles

ABSTRACT In this paper, the movement of the water surface with macroscopic particles during a dam break flow using the volume of fluid (VOF) methods, the discrete phase model (DPM) and macroscopic particle model (MPM) models were numerically simulated. To solve this equation system numerically, the PISO numerical algorithm was chosen. The accuracy of the 3D model and the selected numerical scheme were tested using some laboratory measurements on the destruction of the dam break problem. In the test problem, the values were matched with measurement values and simulation data of other authors. Furthermore, two problems were also considered, the first problem is dam break flow with macroscopic particles, and the second problem – water movement with macroscopic particles, through a heterogeneous terrain and a dam that has a hole. With the help of the problems, the flooding zones and the time of flooding evacuating people from dangerous areas were determined.

The FastEddy® Resident‐GPU Accelerated Large‐Eddy Simulation Framework: Model Formulation, Dynamical‐Core Validation and Performance Benchmarks

AbstractThis paper introduces a new large‐eddy simulation model, FastEddy®, purpose built for leveraging the accelerated and more power‐efficient computing capacity of graphics processing units (GPUs) toward adopting microscale turbulence‐resolving atmospheric boundary layer simulations into future numerical weather prediction activities. Here a basis for future endeavors with the FastEddy® model is provided by describing the model dry dynamics formulation and investigating several validation scenarios that establish a baseline of model predictive skill for canonical neutral, convective, and stable boundary layer regimes, along with boundary layer flow over heterogeneous terrain. The current FastEddy® GPU performance and efficiency gains versus similarly formulated, state‐of‐the‐art CPU‐based models is determined through scaling tests as 1 GPU to 256 CPU cores. At this ratio of GPUs to CPU cores, FastEddy® achieves 6 times faster prediction rate than commensurate CPU models under equivalent power consumption. Alternatively, FastEddy® uses 8 times less power at this ratio under equivalent CPU/GPU prediction rate. The accelerated performance and efficiency gains of the FastEddy® model permit more broad application of large‐eddy simulation to emerging atmospheric boundary layer research topics through substantial reduction of computational resource requirements and increase in model prediction rate.

Comparative study of snake lateral undulation kinematics in model heterogeneous terrain.

Terrestrial organisms that use traveling waves to locomote must leverage heterogeneities to overcome drag on the elongate body. While previous studies illuminated how habitat generalist snakes self-deform to use rigid obstacles in the surroundings, control strategies for multi-component terrain are largely unknown. We compared the sand-specialist Chionactis occipitalis to a habitat generalist, Pantherophis guttatus, navigating a model terrestrial terrain-rigid post arrays on a low-friction substrate. We found the waveshapes used by the generalist were more variable than the specialist. Principal component analysis revealed that while the specialized sand-swimming waveform was always present on C. occipitalis, the generalist did not have a similarly pervasive low-dimensional waveshape. We expected the generalist to thus outperform the specialist in the arrays, but body slip of both species was comparable on level ground and in all trials the snakes successfully traversed the arena. When we further challenged the snakes to ascend an inclined lattice, the sand-specialist had difficulty maintaining contact with the obstacles and was unable to progress up the steepest inclines in the largest lattice spacings. Our results suggest that species adapted to different habitats use different control modalities-the specialist is primarily controlling its kinematics to achieve a target shape while, consistent with previous research, the generalist is using force control and self-deforms in response to terrain contacts. While both strategies allowed progress on the uninclined low-friction terrain with posts, the more variable waveshapes of the generalist may be necessary when faced with more challenging locomotor tasks like climbing inclines.

Local wind speed forecasting based on WRF-HDWind coupling

Wind speed forecasts obtained by Numerical Weather Prediction models are limited for fine interpretation in heterogeneous terrain, in which different roughnesses and orographies occur. This limitation is derived from the use of low-resolution and grid-box averaged data. In this paper a dynamical downscaling method is presented to increase the local accuracy of wind speed forecasts. The proposed method divides the wind speed forecasting into two steps. In the first one, the mesoscale model WRF (Weather Research and Forecasting) is used for getting wind speed forecasts at specific points of the study domain. On a second stage, these values are used for feeding the HDWind microscale model. HDWind is a local model that provides both a high-resolution wind field that covers the entire study domain and values of wind speed and direction at very located points. As an example of use of the proposed method, we calculate a high-resolution wind field in an urban-interface area from Badajoz, a South-West Spanish city located near the Portugal border. The results obtained are compared with the values read by a weathervane tower of the Spanish State Meteorological Agency (AEMET) in order to prove that the microscale model improves the forecasts obtained by the mesoscale model.

Evapotranspiration over Land from a Boundary-Layer Meteorology Perspective

The precise determination of evapotranspiration rate is challenging because it is a quantity that is difficult to measure and to parametrize. Direct estimates include the determination of the change of mass of a volume of soil and vegetation that evapotranspirates using lysimeters, or direct measurements of turbulent water vapour fluxes by eddy-covariance systems. Parametrized estimates that make use of the Monin–Obukhov similarity theory use vertical gradient measurements of temperature and moisture at one point, and line or area averages by means of scintillometers operating at high frequency. A relation for the evapotranspiration from well-watered surfaces was initially developed by Penman and later expanded for vegetated surfaces and for heterogeneous croplands. A popular simplified expression was obtained by Priestley and Taylor. The current challenge is to find expressions for the evapotranspiration in non-saturated conditions, which are common in arid and semi-arid climates, and for heterogeneous terrain. In numerical models, the estimated actual evapotranspiration over land is obtained as the result of the explicit representation of the different involved sub-processes taking place in the soil and the canopy, using so-called land-surface models. Usually these mechanisms are described in a simplified manner and rely on a number of adjustable parameters. The improvement of such descriptions relies in the availability of experimental measurements to make the physical models more complete and robust.

Numerical Simulation of the Water Surface Movement with Macroscopic Particles of Dam Break Flow for Various Obstacles

In this paper, the movement of the water surface with macroscopic particles during a dam break flow using the volume of fluid (VOF) methods and the DPM and MPM models were numerically simulated. The numerical simulation is based on the averaged Navier-Stokes equations, and was closed by the LES turbulent model, representing by the incompressible viscous fluid flow, equations for the phase and particle motion. The PISO numerical algorithm was chosen to solve this equation system numerically. The accuracy of the mathematical model and the selected numerical scheme were compared with experimental measurements on the destruction of the dam break problem. In test problem, the values were matched with measurement values and simulation data of other authors, as well as the improved model illustrated values close to the measured values. A matching was also made of the computational data with measured values using different turbulent models. One problem has been considered, the problem is water movement with macroscopic particles, through a heterogeneous terrain and a dam that has a hole. With the help of the problems, it was determined the flooding zones and the time of flooding evacuating people from dangerous areas.

Identifying priority conservation areas in a Saharan environment by highlighting the endangered Cuvier\u2019s Gazelle as a flagship species

Monitoring populations and designing effective conservation actions for endangered species present significant challenges. An accurate understanding of current distribution, ecological traits and habitat requirements is imperative in formulating conservation strategies. Recent surveys on the southernmost Cuvier’s Gazelle (Gazella cuvieri) population, an ungulate endemic to North Africa, showcase its importance in terms of numbers and genetic diversity. This population inhabits a remote region in the extreme north-western portion of the Sahara Desert and has not been well studied. Here, we examine the potential distribution of Cuvier’s Gazelle and the environmental factors limiting the species in a Saharan environment, by combining broad-scale field survey data and species distribution models. Our objective was to identify high priority conservation areas in the southernmost known portion of the species’ distribution by modelling habitat selection at the landscape scale using a predictive distribution map. Our results show that the distribution of Cuvier’s Gazelle is strongly related to mountainous areas with heterogeneous terrain and remoteness from large human settlements over other ecological factors that had less impact on the species’ presence and distribution. We also provide a quantitative estimate of the potential distribution range of Cuvier’s Gazelle in southern Morocco, identifying two well-demarcated key areas. The two core areas currently contain enough rugged terrain isolated from human encroachment to support the endangered species in this harsh desert environment. We encourage the implementation of conservation planning for Cuvier’s Gazelle as an “umbrella species”, which will confer effective protection to higher-quality habitat zones and co-occurring species, leading to sustainable and ecologically responsible development in the region.

An Induction Curve Model for Prediction of Power Output of Wind Turbines in Complex Conditions

Power generation from wind farms is traditionally modeled using power curves. These models are used for assessment of wind resources or for forecasting energy production from existing wind farms. However, prediction of power using power curves is not accurate since power curves are based on ideal uniform inflow wind, which do not apply to wind turbines installed in complex and heterogeneous terrains and in wind farms. Therefore, there is a need for new models that account for the effect of non-ideal operating conditions. In this work, we propose a model for effective axial induction factor of wind turbines that can be used for power prediction. The proposed model is tested and compared to traditional power curve for a 2.5 MW horizontal axis wind turbine. Data from supervisory control and data acquisition (SCADA) system along with wind speed measurements from a nacelle-mounted sonic anemometer and turbulence measurements from a nearby meteorological tower are used in the models. The results for a period of four months showed an improvement of 51% in power prediction accuracy, compared to the standard power curve.

Modeling the Effects of Topography on Delay-Doppler Maps

A method for simulating delay-Doppler maps (DDMs) of global navigation satellite system signals reflected from land surfaces with heterogeneous terrain is developed from first principles. The method follows previous work for ocean DDMs in the geometric optics limit of the Kirchhoff approximation. Unlike the ocean method, however, where surface heights are assumed to be random with homogeneous statistics, this method decomposes the surface heights into a deterministic part obtained from a digital elevation map (DEM) and a random part representing the residual between the surface and the DEM. The method accounts for the displacement of reflected power into bins of lower delay due to raised surface terrain. The method also provides for the modulation of the normalized bistatic radar cross section by DEM-derived surface slopes over the glistening zone of the DDM. A technique to register Cyclone Global Navigation Satellite System (CYGNSS) DDM bins in delay-Doppler space for land applications is also proposed. The DEM-based method is applied to a CYGNSS track over the Soil Moisture Sensing Controller And oPtimal Estimator (SoilSCAPE) site at Tonzi Ranch, CA, USA. The DEM-based method has potential application for spaceborne monitoring of a variety of environmental parameters.

Snowmelt Detection with Calibrated, Enhanced‐Resolution Brightness Temperatures (CETB) in Colorado Watersheds

AbstractUnderstanding the timing of snowmelt is critical for water resources management in snow‐dominated watersheds. Passive microwave remote sensing can be used to estimate snowmelt events through brightness temperature satellite observations. Previous studies were limited to lower resolution (~25 km or coarser) datasets, making it difficult to quantify snowpack variability in heterogeneous, high‐relief areas. This study investigates the use of recently available Calibrated, Enhanced‐Resolution Passive Microwave Daily EASE‐Grid 2.0 Brightness Temperature ESDR (CETB) to estimate snowmelt timing at much higher spatial resolution (~3‐6 km) than has been previously available. This study investigates the effectiveness of the CETB product for snowmelt detection in several locations in Colorado (North Park, Rabbit Ears, Fraser) that were the sites of previous ground/airborne surveys during the NASA Cold Land Processes Field Experiment (CLPX 2002‐2003), along with data for the Senator Beck Basin from the Center for Snow and Avalanche Studies (CSAS). We compare melt variability with nearby air temperature and stream discharge to show that the new CETB product allows detection of hydrologic processes in mountainous watersheds. We show that the higher resolution CETB product can detect snowmelt in heterogeneous terrain more accurately than the coarser resolution product in terms of the number of winter melt events and seasonal melt onset date. This work lays the foundation for the utilization of higher resolution reprocessed CETB data for snowpack evolution more broadly in a range of environments.

Adaptive neuro-fuzzy inference system based on-the-move terrain classification for autonomous wheeled mobile robots

Building intelligence in autonomous robots to classify heterogeneous terrains on-the-move is a challenging task, but a pivotal feature required for accomplishing safety critical missions. This paper proposes an adaptive neuro-fuzzy inference system for online terrain classification in the wheeled mobile robot using the steady-state behaviour of robot wheel on the terrain. The key idea is to model the wheel-terrain interactions as a parametric varying system, whose steady-state behaviours are characterised by the terrain type. The proposed method uses the steady state gains and the corresponding input command to robot wheel for identifying the terrain type. Our results show that the proposed approach has a classification accuracy of 95.2% for the trained terrains, whereas 94.2% and 93.8% are observed in robust and adaptive testing, respectively. Additionally, a customised graphical user interface is developed to provide easy access to the researchers for terrain identification.

Multiparametric coupling and constrained interpolation to improve natural recharge estimation

The inverse modelling technique seeks to improve the existing estimates of natural recharge in hard rocks by coupling multiple hydrogeophysical parameters that jointly affect natural hydrogeological processes. This approach involves coupling of an initial set of multiple hydrogeophysical (soil resistivity, bedrock depth and rainfall) parameters in the form of exponents assigned to each parameter and a multiplication coefficient to obtain natural recharge. These model parameters (i.e., exponents and coefficients) are then quantified using linear least squares inversion against the known recharge values. To reduce the effect of geomorphic heterogeneity, viz., hills on natural recharge, laterally constrained inversion has been employed to integrate data sets (e.g., recharge measured at various points and logical expectation over exposed hills in an area) and constrained interpolation is then carried out along the grid lines for increased data density. Finally, Kriging interpolation over dense data obtained through data integration and constrained interpolation is used to significantly minimise the risks of overshooting the observations. Thus, the present approach provides a realistic spatial distribution of natural recharge values in a highly heterogeneous hard rock terrain.

Observed Atmospheric and Surface Variability on Heterogeneous Terrain at the Hectometer Scale and Related Advective Transports

AbstractThe values of the atmospheric variables follow from mass, momentum, and energy conservation equations. These equations involve gradients which, in heterogeneous terrain, lead to a connection of the values at one point to the values in their nearby surroundings, due to turbulence mixing or advective local transports. In this work the observed variability of the air and soil variables is analyzed for a 1‐km2 surface in a semirural area for a number of weather stations separated typically 150 m. Data show a large variability at the hectometer scale, with several degrees of difference in temperature sustained in time between neighboring points. While in the daytime turbulence contributes to keep the differences moderate, in weak wind nights the spatial variability increases significantly. The variability of soil variables can be large depending on the soil moisture and the vegetation cover and is less sensitive to the diurnal cycle. The inspection of the vertical gradients of temperature and humidity reveals that their sign and intensity, and consequently the corresponding sensible and latent heat fluxes, differ depending on the measuring point. The thermal advection is obtained from the hectometer‐scale network, which is comparable in magnitude to the turbulent fluxes and to the imbalance of the surface energy budget for clear and calm nights. During the day, the advection term may explain part of the energy budget imbalance, particularly when it is computed on a 30‐min time scale. A similar method is applied to the water vapor, finding that in the very dry conditions of the experiment, moisture advection is significant and with values comparable to the evapotranspiration.

Comparing Spectral Characteristics of Landsat-8 and Sentinel-2 Same-Day Data for Arctic-Boreal Regions

The Arctic-Boreal regions experience strong changes of air temperature and precipitation regimes, which affect the thermal state of the permafrost. This results in widespread permafrost-thaw disturbances, some unfolding slowly and over long periods, others occurring rapidly and abruptly. Despite optical remote sensing offering a variety of techniques to assess and monitor landscape changes, a persistent cloud cover decreases the amount of usable images considerably. However, combining data from multiple platforms promises to increase the number of images drastically. We therefore assess the comparability of Landsat-8 and Sentinel-2 imagery and the possibility to use both Landsat and Sentinel-2 images together in time series analyses, achieving a temporally-dense data coverage in Arctic-Boreal regions. We determined overlapping same-day acquisitions of Landsat-8 and Sentinel-2 images for three representative study sites in Eastern Siberia. We then compared the Landsat-8 and Sentinel-2 pixel-pairs, downscaled to 60 m, of corresponding bands and derived the ordinary least squares regression for every band combination. The acquired coefficients were used for spectral bandpass adjustment between the two sensors. The spectral band comparisons showed an overall good fit between Landsat-8 and Sentinel-2 images already. The ordinary least squares regression analyses underline the generally good spectral fit with intercept values between 0.0031 and 0.056 and slope values between 0.531 and 0.877. A spectral comparison after spectral bandpass adjustment of Sentinel-2 values to Landsat-8 shows a nearly perfect alignment between the same-day images. The spectral band adjustment succeeds in adjusting Sentinel-2 spectral values to Landsat-8 very well in Eastern Siberian Arctic-Boreal landscapes. After spectral adjustment, Landsat and Sentinel-2 data can be used to create temporally-dense time series and be applied to assess permafrost landscape changes in Eastern Siberia. Remaining differences between the sensors can be attributed to several factors including heterogeneous terrain, poor cloud and cloud shadow masking, and mixed pixels.

On the Predictability of Radiation Fog Formation in a Mesoscale Model: A Case Study in Heterogeneous Terrain

This study evaluates the predictability of the formation phase of a radiation fog event observed during the night of 31 October 2015 to 01 November 2015 in the north-east of France at three sites managed by OPE (Observatoire Pérenne de l’Environnement). The fog layer shows significantly different behaviors at the three areas, which are located only a few kilometers apart. Three fog life cycles were observed: the formation of a dense adiabatic fog, the formation of a thin patchy fog, or no fog formation despite favorable conditions. This event was studied with the Meso-NH numerical mesoscale model at two horizontal resolutions, 500 m and 50 m. Simulations at 50 m allow estimation of the spread of the predicted parameters over the heterogeneous terrain studied. These numerical simulations strongly suggest that this event involved numerous interactions and complex circulations. The wind above the nocturnal boundary layer greatly affects the transition of shallow patchy fog into thick adiabatic fog. These numerical simulations also show that the occurrence and type of fog could be very different over a small but heterogeneous area. It is also interesting to note that the spread of the simulated parameters was very high during the transition from shallow fog to a deep fog layer. The spread was concentrated during the regime transition between the fog formation and its maturity. This appeared to be the result of the complex interplay of processes at numerous ranges of scale. A new concept called “pseudo-process diagram” is presented. These pseudo-process diagrams are very good tools to analyze fog, and allow a good illustration of the spread of fog during this chaotic phase. This kind of concept seems a promising tool to analyze fog predictability in depth.

Local environmental controls of Atlantic Forest tree community assembly on a coastal continental island in southeastern Brazil

ABSTRACT Tropical forests with high species diversity are commonly found in rugged montane areas. We investigated causes of local tropical forest tree community assembly on a continental island with heterogeneous terrain. We recorded tree community (absolute species abundance), topography, soil, litter and location in 40 sampling units on two opposite sides of the island with similar heterogeneous terrain. We used transformation based Redundancy Analyses and variation partitioning to determine the contribution of environment (topography, soil and litter), spatial structure (geographic location and Moran Eigenvector Maps) and the shared effects of these to explain community assembly. The environment made a significant contribution to explain tree community patterns (species composition and abundance) across all models. Conversely, spatial structure showed minor impact. Contribution of strictly environmental effects and spatially structured environmental effects varied when evaluating each site independently as well as when evaluating the combined data. Evidence suggests that local tropical tree community assembly on heterogeneous terrain may be located much closer to the niche end of the hypothetic niche-neutral continuum. Findings indicate additionally that heterogeneity of environmental factors present in dissected mountainous terrain can affect the way tropical community assembly processes are perceived.

"Nine Dimensions": A multidisciplinary approach for community engagement in a complex postwar border region as part of the targeted malaria elimination in Karen/Kayin State, Myanmar.

Background: In light of growing antimalarial drug resistance in Southeast Asia, control programmes have become increasingly focused on malaria elimination, composed of mass drug administration coupled with prompt diagnosis and treatment of symptomatic cases. The key to a successful elimination programme centres on high participation rates in targeted communities, often enhanced by community engagement (CE) efforts. Social science research was conducted to develop a conceptual framework used for CE activities in the Targeted Malaria Elimination programme, as a cross-border operation in Karen/Kayin State, Myanmar. Methods: Data was collected from three main sources: (1) participant observation and semi-structured interviews of CE team members; (2) participant observation and semi-structured interviews with villagers; and (3) records of CE workshops with CE workers conducted as part of the TME programme. Results: Interviews were conducted with 17 CE team members, with 10 participant observations and interviews conducted with villagers and a total of 3 workshops conducted over the course of this pilot programme in 4 villages (November 2013 to October 2014). Thematic analysis was used to construct the nine dimensions for CE in this complex, post-war region: i) history of the people; ii) space; iii) work; iv) knowledge about the world; v) intriguing obstacle (rumour); vi) relationship with the health care system; vii) migration; viii) logic of capitalism influencing openness; and ix) power relations. Conclusions: Conducting CE for the Targeted Malaria Elimination programme was immensely complicated in Karen/Kayin State because of three key realities: heterogeneous terrains, a post-war atmosphere and cross-border operations. These three key realities constituted the nine dimensions, which proved integral to health worker success in conducting CE. Summary of this approach can aid in infectious disease control programmes, such as those using mass drug administration, to engender high rates of community participation.