Citizen Science: Environmental Sensing

Measuring Air Pollution in Amsterdam | Hindawi Blog

The third guest blog post of our ‘Opening Science’ series is written by Qijun Jiang, and discusses his contribution to urban environmental monitoring. Qijun is a PhD candidate researching sensor and environmental monitoring in the Laboratory of Geo-information Science and Remote Sensing at Wageningen University & Research, and is a Member of the European Citizen Science Association (ECSA) and of the Citizen Science and Open Science Working Group within ECSA.
Contact: @SensorDataLab,

Environmental issues such as the pollution of air, water, and soil harm human health and our planet. To understand the state of the environment, and make smart decisions when forming our future policies, we need robust environmental data. Often, these data are collected by official organizations using large-scale and expensive monitoring stations to yield high quality data, but with a limited frequency or number of locations. As a result, citizens and policy makers may not have sufficient information to make informed decisions and optimal strategic determinations.

Citizen science has the potential to make a huge impact, and help solve some of the key environmental considerations confronting our society.

Thanks to the development of sensor technology, and open hardware and software movements, citizens can now measure their surroundings in a way which was not possible before. Sensors are becoming smaller, cheaper and better. By connecting sensors with open hardware, citizens can make the necessary tools to measure environmental pollution themselves. They can take measurements almost anywhere, anytime, and see the data on their smartphones and computers. In this way, the public are more engaged in science throughout the whole process, from raising questions, making tools and collecting data, to answering those questions and making decisions or taking actions. Citizen science has the potential to make a huge impact, and help solve some of the key environmental considerations confronting our society.

Qijun explains the project

Qijun chats with some citizen scientists in a community meeting

That said, some experts have criticized the quality of data arising from such initiatives, and these sentiments have the potential to demoralize previously engaged citizens. Instead, we should be encouraging experts and scientists to embrace public involvement, and provide tools and guidance to make them better citizen scientists, or even co-create science with citizens. In turn experts and scientists can benefit from the generation of big data and other outcomes, for information provision and scientific research.

In an earlier citizen-focused environmental sensing pilot project in Amsterdam, some participants were excited about using a sensing kit, but were also disappointed by its air sensors which proved to be unsuitable for urban air quality monitoring. To solve the problem, I joined the new project called Amsterdam Smart Citizens Lab. There, I introduced an electrochemical sensor to a group of citizens, air quality experts, and developers, and together we developed a working prototype. Preliminary testing was very positive, most people were excited about the improved results ­— which we went on to publish in the Journal of Sensors. Based on that success, a follow up project called Urban AirQ was initiated, funded by the Amsterdam Institute for Advanced Metropolitan Solutions and the EU Making Sense project. There, a group of experts, scientists, and community managers worked together with citizens trying to learn more about their local environment. We further tested the sensor capabilities by focusing on calibration against official monitoring stations. Much to the surprise of the experts — and joy of the citizens — the sensors proved valuable for urban air quality monitoring.

air quality sensor device

One of the developed air quality sensor devices, connected by Bluetooth to a smartphone ready for data sharing applications

The experience of working with citizens, community managers, and experts from official organizations has taught me a lot. I better understand how citizens can be motivated for scientific pursuit, how scientists can make more positive societal impact by opening up science, and the benefits of joining and supporting citizen science initiatives. I have since joined the European Citizen Science Association (ECSA), and collaborate with members from the Citizen Science Association (CSA) and the Australian Citizen Science Association (ACSA), as well as other broader citizen science communities for improved citizen science, environmental sensing, and open science. I am currently building a GitHub page at to share both my research and the open source technology that I developed.

The text, profile photo, and sensor photo are by Qijun Jiang. The discussion photo is by the Waag Society. The illustration and journal cover is by Hindawi. All are distributed under the Creative Commons Attribution License (CC-BY).