A project to track pollen movement highlights the public health potential of aerial photography datasets
Efforts to use aerial photography in public health initiatives have gathered momentum with a project, run by the Met Office, University of Exeter Medical School and London School of Hygiene and Tropical Medicine, to produce an environmental dataset on how concentrations of trees relate to hay fever.
The organisations are using the National Tree Map, produced by aerial survey specialist Bluesky, to develop species-specific maps of allergenic pollen. These will be combined with detailed models of how pollen is likely to move and behave in the atmosphere, enabling researchers to assess its links with allergic diseases such as hay fever and asthma, and to examine other health implications.
Met Office scientists are planning to use National Tree Map data with other land use maps, vegetation and datasets to look at where and when the pollen is produced, and how and where it is likely to travel, taking into account species characteristics and climatological impacts.
The project highlights the broader potential to use aerial photography datasets in investigating public health issues.
Dr Rachel McInnes, senior climate scientist at the Met Office Hadley Centre, tells UKAuthority: "There is a great potential to use aerial photography in public health research.
"We are using large datasets on vegetation and land use taken from satellites and aerial photography. A lot of mapping products can help you to identify types of vegetation on the ground, and at a basic level if you have more information about vegetation you can learn more about health.
"For example, tree maps can help you to assess different health impacts, and pollen movements can influence hay fever and asthma, and you can look at ozone levels. You can also look at the effect of green spaces on wellbeing, combining it with information such as hospital admissions and GP records."
One year to results
McInnes says the pollen project has been running for a year but the Met Office has only begun to use the National Tree Map recently, receiving data for one month, and it will be a year or so before it yields any clear results.
The map is produced from high resolution aerial photography and infrared data, and shows more than 280 million trees over 20,000 sq km. McInnes says it is particularly useful as it provides details the Met Office's other datasets did not cover, notably the location of trees in urban areas, small wooded areas and hedgerows. This will help to make the pollen maps more accurate.
"Different types of pollen are released from different plants and trees at different times of the year," she says. "These can trigger hay fever and other allergies that can have a serious impact on the health and wellbeing of sufferers.
"By understanding where and when allergens are produced and how they are affected by weather and climate, we can gain a better understanding of their impact on health and provide more accurate and detailed forecasts."
Rachel Tidmarsh, managing director of Bluesky, says that aerial photography datasets such as the National Tree Map are not in themselves public health tools, but have potential for research when they are combined with other datasets.
"It's not us using the data, but we create and sell it to organisations that use it with their applications," she says, adding: "For health issues it's about correlations such whether it's occurring near specific things like busy roads or power stations."
Air quality project
Another project in which the company has a more direct involvement - sponsoring a PhD student in atmospheric physics at the University of Leicester - is using a specialised airborne mapping system integrated with ground based sensors to monitor harmful gases in urban environments. It involves the use of a device mounted on an aerial survey aircraft to measure light and its relationship with levels of nitrogen dioxide, and uses data from the National Tree Map.
As well as measuring pollution levels, the project is looking at vertical mixing ratios of air and the potential impact of buildings and trees.
The PhD student, Jordan White, said at the time the project was launched: "By exploring the complex concepts of gas-phase tomography we can retrieve 3D structures of pollution. This, combined with improvements in the performance and integration of the monitoring systems, gives us a much better understanding of the levels and movement of air pollution in our cities."
Rachel McInnes says that highlighting trends in air quality and pollution is one of the main areas of potential for aerial photography, and that a detailed picture of vegetation in an area is very helpful in the research. But there are broader possibilities for which there has so far been little research.
"We can also look at the effects of green spaces in urban areas," she says. "If we can quantify them in different areas it can feed into studies on general wellbeing and mental health issues. I should think there would be plenty more areas we could investigate."
Picture from Bluesky