Gemma Davies

Understanding the School Journey: Integrating Data on Travel and Environment

Travel to and from school is a regular part of life for most children. Such movement can also have important social, economic, and environmental implications, both for individuals and for wider society. This paper uses innovative methods to examine the complexity of the school journey, and to relate it to exposure to air pollution and engagement with the environment through which children pass. Some thirty lower secondary school pupils used mobile phone and global positioning system technology to record their routes to and from school in four study periods. They were asked to take photographs and write text messages relating to their route, and these data were then linked to modelled air pollution on the routes through which pupils travelled. Results demonstrate that for most children the journey to and from school is highly variable and contingent on other factors. Pupils who travelled independently (on foot, by bicycle, or by bus) were most likely to engage with their immediate environment, and small variations in route choice had significant effects on their cumulative exposure to air pollution. It is argued that the results shed new light on the everyday experience of the school journey, and have implications for health promotion and transport planning in towns.

The ecological impact of city lighting scenarios: exploring gap crossing thresholds for urban bats

Abstract As the global population urbanizes, dramatic changes are expected in city lighting and the urban form, which may threaten the functioning of urban ecosystems and the services they deliver. However, little is known about the ecological impact of lighting in different urban contexts. Movement is an important ecological process that can be disrupted by artificial lighting. We explored the impact of lighting on gap crossing for Pipistrellus pipistrellus, a species of bat (Chiroptera) common within UK cities. We aimed to determine whether the probability of crossing gaps in tree cover varied with crossing distance and lighting level, through stratified field surveys. We then used the resulting data on barrier thresholds to model the landscape resistance due to lighting across an entire city and explored the potential impact of scenarios for future changes to street lighting. The level of illumination required to create a barrier effect reduced as crossing distance increased. For those gaps where crossing was recorded, bats selected the darker parts of gaps. Heavily built parts of the case study city were associated with large and brightly lit gaps, and spatial models indicate movement would be highly restricted in these areas. Under a scenario for brighter street lighting, the area of accessible land cover was further reduced in heavily built parts of the city. We believe that this is the first study to demonstrate how lighting may create resistance to species movement throughout an entire city. That connectivity in urban areas is being disrupted for a relatively common species raises questions about the impacts on less tolerant groups and the resilience of bat communities in urban centres. However, this mechanistic approach raises the possibility that some ecological function could be restored in these areas through the strategic dimming of lighting and narrowing of gaps.

Mapping Lightscapes: Spatial Patterning of Artificial Lighting in an Urban Landscape

Artificial lighting is strongly associated with urbanisation and is increasing in its extent, brightness and spectral range. Changes in urban lighting have both positive and negative effects on city performance, yet little is known about how its character and magnitude vary across the urban landscape. A major barrier to related research, planning and governance has been the lack of lighting data at the city extent, particularly at a fine spatial resolution. Our aims were therefore to capture such data using aerial night photography and to undertake a case study of urban lighting. We present the finest scale multi-spectral lighting dataset available for an entire city and explore how lighting metrics vary with built density and land-use. We found positive relationships between artificial lighting indicators and built density at coarse spatial scales, whilst at a local level lighting varied with land-use. Manufacturing and housing are the primary land-use zones responsible for the city’s brightly lit areas, yet manufacturing sites are relatively rare within the city. Our data suggests that efforts to address light pollution should broaden their focus from residential street lighting to include security lighting within manufacturing areas.

Talk, technologies and teenagers: understanding the school journey using a mixed-methods approach

This paper focuses on the methods used in a project which set out to capture the movements and to consider the wellbeing of 30 teenagers on their journeys to and from school. A mobile phone linked to a GPS receiver was used to automatically log travel patterns whilst the respondents added ‘blog’ images and text about how they felt on the journey. Follow up interviews further explored the data. The paper shows that by using a range of methods the young people became involved in the project in different ways providing a rich picture of contingent and complex school journeys.

How reliable are citizen‐derived scientific data? : assessing the quality of contrail observations made by the general public

Citizen science projects encourage the general public to participate in scientific research. Participants can contribute large volumes of data over broad spatial and temporal frames; however the challenge is to generate data of sufficient quality to be useable in scientific research. Most observations made by citizen‐scientists can be independently verified by ‘experts’. However, verification is more problematic when the phenomena being recorded are short‐lived. This paper uses a GIS methodology to verify the quality of contrail observations made by the general public as part of the OPAL Climate Survey. We verify observations using datasets derived from a variety of different sources (experts, models and amateur enthusiasts) with different spatial and temporal properties which reflect the complex 3D nature of the atmosphere. Our results suggest that ~70% of citizen observations are plausible based on favourable atmospheric conditions and the presence or absence of aircraft; a finding which is in keeping with other, more conventional citizen science projects. However, questions remain as to why the quality of the citizen‐based observations was so high. Given the lack of supporting data on observers, it is impossible to determine whether the dataset was generated by the activities of many participants or a small but dedicated number of individual observers.

Runoff processes in Southeast Asia: role of soil, regolith and rock type.

Runoff processes govern the river hydrograph form, location of return-flow and biogeochemical water quality of tropical forest watersheds. This study reviews the literature on runoff processes from tropical rainforests and applies it to the situation in tropical Southeast Asia. The impact of clay mineralogy on permeability and thence water pathways within the soil, and the role of deep pathways with unconsolidated geological materials (regolith) or permeable rock (solid geology) are emphasised, and a new perceptual model, DELTAmodel, presented. Lastly, the implications of these findings for runoff processes within the Mekong Basin are discussed.

A Least‐Cost Approach to Personal Exposure Reduction

Concerns over the potential negative health effects from exposure to air pollution have led to interest in assessing personal exposure and finding ways to reduce it. As journey-time exposure accounts for a disproportionately high amount of an individual’s total exposure, this article assesses the potential to apply least-cost techniques within a GIS in order to identify paths of lower journey-time exposure. The methodology adopted uses pollution surfaces for PM10 and CO generated by the dispersion model ADMS, with an analysis mask derived from OS MasterMap to create a least-cost surface. Actual routes taken by a cohort of 11–13 year old children on their journeys to school are used to compare observed journey time exposure with the exposure along alternative routes generated using the least-cost path function. While the least-cost approach proved to be successful in defining low exposure routes the ability to scale up this approach is constrained by the amount of editing required to successfully create an analysis mask from OS MasterMap data. Such alternative routes have the potential to assist in promoting safer environmental choices, however, their likelihood of adoption is dependant on a number of social and environmental influences which affect an individual’s route choice.

Teaching Geographical Information Systems in Geography Degrees: A Critical Reassessment of Vocationalism

Geographical information systems (GIS) are in tune with the current ethos of higher education because of their perceived vocational value. However, it is particularly difficult to teach GIS vocationally. This paper critiques the claim of vocationalism. The authors use an innovative method of evaluating a module that enlists its alumni to reflect on the career value of their GIS teaching. The survey was analysed to show how, to what extent and for which graduates GIS had been vocationally useful. The paper concludes that GIS is vocational but in variable and complex ways for different students.

A network-based approach for estimating pedestrian journey-time exposure to air pollution

Individual exposure to air pollution depends not only upon pollution concentrations in the surrounding environment, but also on the volume of air inhaled, which is determined by an individuals physiology and activity level. This study focuses on journey-time exposure, using network analysis in a GIS environment to identify pedestrian routes between multiple origins and destinations throughout the city of Lancaster, North West England. For each segment of a detailed footpath network, exposure was calculated accounting for PM2.5 concentrations (estimated using an atmospheric dispersion model) and respiratory minute volume (varying between individuals and with slope). For each of the routes generated the cumulative exposure to PM2.5 was estimated, allowing for easy comparison between multiple routes. Significant variations in exposure were found between routes depending on their geography, as well as in response to variations in background concentrations and meteorology between days. Differences in physiological characteristics such as age or weight were also seen to impact journey-time exposure considerably. In addition to assessing exposure for a given route, the approach was used to identify alternative routes that minimised journey-time exposure. Exposure reduction potential varied considerably between days, with even subtle shifts in route location, such as to the opposite side of the road, showing significant benefits. The method presented is both flexible and scalable, allowing for the interactions between physiology, activity level, pollution concentration and journey duration to be explored. In enabling physiology and activity level to be integrated into exposure calculations a more comprehensive estimate of journey-time exposure can be made, which has potential to provide more realistic inputs for epidemiological studies.

Using mobile phones to reveal the complexities of the school journey

In this paper, we present findings of a research project in which mobile phones were used as part of a multi-methods approach to analyze the effects of air pollution on childrens journeys to and from school. In particular, we will present the results from the space-time blogs generated by 30 Year 8 pupils (aged 12--13) on their school journeys during four periods of study across the seasons of a year. The blogs were generated by the teenagers using a specially created application running on a mobile phone linked to a Bluetooth GPS unit and consist of spatially and temporally-referenced texts and images together with a record of their route using GPS coordinates stored at one second intervals. Whilst the blogs generated considerable amounts of quantitative information, particularly when coupled with the pollution profiles of the routes the teenagers travelled, it is the depth of qualitative information revealed in the interviews with the teenagers after each study period, using the routes and blogs as a trigger, that demonstrates the benefits of the multi-methods approach. In particular, we highlight some of the depth of contextual information revealed not only in regard to the use of the phone application and GPS unit but also the complex social factors which contribute to formation of the school journey.