Surface representation impacts on turbulent heat fluxes in the Weather Research and Forecasting (WRF) model (v.4.1.3)

The water and energy transfers at the interface between the Earth's surface and the atmosphere should be correctly simulated in numerical weather and climate models. This implies the need for a realistic and accurate representation of land cover (LC), including appropriate parameters for each vegetation type. In some cases, the lack of information and crude representation of the surface lead to errors in the simulation of soil and atmospheric variables. This work investigates the ability of the Weather Research and Forecasting (WRF) model to simulate surface heat fluxes in a heterogeneous area of southern France using several possibilities for the surface representation. In the control experiments, we used the default LC database in WRF, which differed significantly from the actual LC. In addition, sub-grid variability was not taken into account since the model uses, by default, only the surface information from the dominant LC category in each pixel (dominant approach). To improve this surface simplification, we designed three new interconnected numerical experiments with three widely used land surface models (LSMs) in WRF. The first one consisted of using a more realistic and higher-resolution LC dataset over the area of analysis. The second experiment aimed at investigating the effect of using a mosaic approach; 30 m sub-grid surface information was used to calculate the final grid fluxes based on weighted averages from values obtained for each LC category. Finally, in the third experiment, we increased the model stomatal conductance for conifer forests due to the large flux errors associated with this vegetation type in some LSMs. The simulations were evaluated with gridded area-averaged fluxes calculated from five tower measurements obtained during the Boundary-Layer Late Afternoon and Sunset Turbulence (BLLAST) field campaign. The results from the experiments differed depending on the LSM and displayed a high dependency of the simulated fluxes on the specific LC definition within the grid cell, an effect that was enhanced with the dominant approach. The simulation of the fluxes improved using the more realistic LC dataset except for the LSMs that included extreme surface parameters for coniferous forest. The mosaic approach produced fluxes more similar to reality and served to particularly improve the latent heat flux simulation of each grid cell. Therefore, our findings stress the need to include an accurate surface representation in the model, including soil and vegetation sub-grid information with updated surface parameters for some vegetation types, as well as seasonal and man-made changes. This will improve the modelled heat fluxes and ultimately yield more realistic atmospheric processes in the model.

Children's perspectives on outdoor play programs in childcare centre playgrounds: are early childhood educators listening?

Outdoor programs are part of children’s everyday experiences in childcare centres. However, there is a lack of research that explores children’s viewpoints on their outdoor programs in childcare centres. This qualitative study examined children’s perspectives using the Mosaic approach. In addition, the early childhood educators (ECEs) were interviewed to investigate how they learn about and support children’s interests. Findings indicate that using the Mosaic approach can contribute to a more holistic understanding of children’s perspectives of their outdoor play programs. Findings also indicate that ECEs use observation and communication to learn about children’s interests. The ECEs also stated that they support children’s interests during their outdoor programs through verbal support and modelling, changing and expanding activities, and preparing various activities and materials for the children. Discussion on the findings explores multiple methods for tapping children’s perspectives, implications for teacher practices, and direction for future research.

Children's perspectives on outdoor play programs in childcare centre playgrounds: are early childhood educators listening?

Outdoor programs are part of children’s everyday experiences in childcare centres. However, there is a lack of research that explores children’s viewpoints on their outdoor programs in childcare centres. This qualitative study examined children’s perspectives using the Mosaic approach. In addition, the early childhood educators (ECEs) were interviewed to investigate how they learn about and support children’s interests. Findings indicate that using the Mosaic approach can contribute to a more holistic understanding of children’s perspectives of their outdoor play programs. Findings also indicate that ECEs use observation and communication to learn about children’s interests. The ECEs also stated that they support children’s interests during their outdoor programs through verbal support and modelling, changing and expanding activities, and preparing various activities and materials for the children. Discussion on the findings explores multiple methods for tapping children’s perspectives, implications for teacher practices, and direction for future research.

Surface representation impacts on turbulent heat fluxes in WRF (v.4.1.3)

The water and energy transfers at the interface between the Earth's surface and the atmosphere should be correctly simulated in numerical weather and climate models. This implies the need for a realistic and accurate representation of land cover (LC), including appropriate parameters for each vegetation type. In some cases, the lack of information and crude representation of the surface leads to errors in the simulation of soil and atmospheric variables. This work investigates the ability of the Weather Research and Forecasting (WRF) model to simulate surface heat fluxes in a heterogeneous area of southern France, using several possibilities for the surface representation. In the control experiments, we used the default LC database in WRF, which differed significantly from the actual LC. In addition, sub-grid variability was not taken into account since the model uses, by default, only the surface information from the dominant LC category in each pixel (dominant approach). To improve this surface simplification, we designed three new interconnected numerical experiments with four widely-used land-surface models (LSMs) in WRF. The first one consisted of using a more realistic and higher-resolution LC dataset over the area of analysis. The second experiment aimed at investigating the effect of using a mosaic approach, where 30-m sub-grid surface information was used to calculate the final grid fluxes, based on weighted averages from values obtained for each LC category. Finally, in the third experiment, we increased the model stomatal conductance for conifer forests, due to the large fluxes errors associated with this vegetation type in some LSMs. The simulations were evaluated with gridded area-averaged fluxes calculated from five tower measurements obtained during the Boundary Layer Late Afternoon and Sunset Turbulence (BLLAST) field campaign. The results from the experiments differed depending on the LSM and displayed a high dependency of the simulated fluxes on the specific LC definition within the grid cell, an effect that was enhanced with the dominant approach. The simulation of the fluxes improved using the more realistic LC dataset except for the LSMs that included extreme surface parameters for the coniferous forest. The mosaic approach produced fluxes more similar to reality and served to improve, especially, the latent heat flux simulation of each grid cell. Therefore, our findings stress the need to include an accurate surface representation in the model, including soil and vegetation sub-grid information with updated surface parameters for some vegetation types, as well as seasonal and man-made changes. This will improve the modelled heat fluxes and ultimately yield more realistic atmospheric processes in the model.

Uncertainty and practical judgement in research: a call for attentive ‘listening’

This paper draws upon research projects in which efforts have been made to find ways of listening to young children’s voices in early years contexts. This listening, namely in the mosaic approach, helps us to see how children make sense of their world, and adopt our planning and ‘being with’ young children. After setting the context of early years pedagogy and ideology of mosaic approach, this paper focuses on the researcher’s journey to turn her gaze inward before making any claims about her engagement with and listening to young children. Since this approach purposely leaves unanswered the question what kind of data is going to be collected, researchers have to decide what data is in the course of a research project, through their engagement with children. We argue for befriending uncertainty and dilemmatic thinking as it provides us with a different way of seeing, knowing and listening the hard to know. Through writing about phronêsis, this paper focuses on the process of decision-making and judgements that researchers undertake. The final argument calls for attentiveness and aims to acknowledge practical judgements as a fundamental part of researching early years.