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Citizen Science Projects in Germany

Updated: Aug 4, 2022

The third article in our 'CS landscape series' looks at Citizen Science projects in Germany. The ensuing analysis is based on a critical review of 29 initiatives that were organised or are still running in the country. Interested readers can download the dataset developed during the mapping process where all 29 initiatives are presented and analysed in greater detail. For methodology and limitations of the research undertaken, please refer to the foundational article.

When building the German sample, our priority was to include 1) all the main projects that deal with air quality and traffic monitoring, 2) local projects that seem to be popular in the capital e.g. wildlife monitoring, 3) European or international projects with CS activities in the capital and other parts of Germany, and 4) interesting examples that don’t conduct any CS activities per se, but which support the growth of Germany’s CS culture and community. What initiatives made it to the landscape review can be seen in the table below.

General overview

Notwithstanding its limitations, our sample provides a snapshot of the highly diverse CS landscape in Germany. We found initiatives that originated in Germany but have since spread to other countries in Europe and beyond (the so-called ‘inside-out’ initiatives), and initiatives that completed the opposite journey i.e. they started elsewhere but ended up running CS activities in Germany (the ‘outside-in’ initiatives). Although we came across several EU funded projects in various domains, our impression is that the vast majority of German initiatives are actually initiated, funded and managed by domestic actors. We were also surprised by the discovery of an interesting initiative type that provides support to CS projects but doesn’t necessarily conduct any CS experiments itself. To better illustrate this diversity, we’ll briefly present a couple of projects from each category, and will then delve deeper into the sample by examining key themes related to stakeholder engagement, data collection, and impact.

‘Inside-out’ initiatives

Examples of initiatives that started in Germany and eventually spread to other countries are Sensor.Community and Plastik Pirates. Sensor.Community is a continuation of that was started by the OK Lab Stuttgart in 2016. Sensor.Community is now a global sensor network that includes 14400 devices and is active in 73 countries. Driven by the principles of CS, Open Data and transparency, Sensor.Community has launched a number of campaigns to bring sensors to every school (#Sensor2School), library (#Sensor2Library) and reference station (#Sensor@RefS).

Plastik Pirates started as a campaign to investigate plastic waste in German rivers. A few years later, the Trio-Presidency of the Council of the European Union for 2020/2021 led by Germany, Portugal and Slovenia, decided to scale up the project to all countries involved. Since then, thousands of young people have taken part as citizen scientists by collecting plastic waste and sharing data on the amount of waste found. The new sampling period will start in spring 2022.

‘Outside-in’ initiatives (European, international)

To this category belong international initiatives like HEAL and GLOBE. We first introduced HEAL in the Bulgarian chapter, because Sofia was one of six cities targeted by the project. Berlin is another. According to HEAL, the city's annual EU standard for NO2 was exceeded year after year and PM10 standards were not properly complied with since 2009. In response to that, HEAL started a CS monitoring project in 2019, with the active participation of ten schools[1] across Berlin representing approximately 4300 children.

GLOBE, as the name suggests, is a global initiative covering 125 countries that was founded in the US in 1994 to improve understanding of the Earth system and environment among students and the public worldwide. In this deliverable, GLOBE too was first introduced in the Bulgarian chapter. When comparing Bulgarian and German “arms” of the initiative, we noticed that the former had no country coordinator, whereas the latter has not only the coordinator, there is also a dedicated website (in German) and regular reporting.[2] In terms of numbers, GLOBE Germany has worked with 615 schools, 322 teachers and 7307 students, producing a total of 7034 measurements across 1992 German CS sites.[3]

EU-funded projects

EU-funded CS projects that had pilot activities in Germany include the likes of hackAIR and DNOSES. hackAIR positioned itself as an open technology platform for accessing information on air quality, thermal comfort and probability of forest fires in Europe. CS activities took place in Germany, Greece, Belgium and Norway. Participants in the German pilot (Berlin) actively participated in data collection (using largely the same sensors as Sensor.Community) and analysis. They helped with coding and supported other sensor users, with some eventually becoming ambassadors for the project.

Focusing on odour pollution, DNOSES built a special OdourCollect app that citizens could use to report odour nuisance, its source and intensity, with results then displayed on the OdourCollect map. Although Berlin has some markers there (actually just three), the highest number of markers is in Shermbeck. In total, there seem to be around 50 markers across the whole of Germany.

Domestic initiatives

Two examples from this group are Open Soil Atlas and BeachExplorer. Open Soil Atlas was started by FeldFoodForest with a dual objective: to educate the public about soil quality in Berlin and to demonstrate the relationship between healthy soil and healthy communities. A CS round that took place in 2021 involved 80 Berliners in soil measurements, who produced a total of 77 datasets with information on soil coordinates, land use, soil colour, soil profile, percentage of sand and clay, and pH test, to name just a few parameters.

BeachExplorer is an initiative of the Wadden Sea Conservation Station that has been running mostly in Northern Germany since 2012. By leveraging CS and promoting the understanding of marine nature, the project supports the federal program on biological diversity. Over 10 years that the project has been in existence, more than 4000 citizen scientists have made close to 40000 observations (though some of these are shared between Germany, Denmark and the Netherlands).

Supporting initiatives

As already mentioned, this category includes initiatives whose mission is to support CS culture in Germany, but which don’t necessarily qualify as a CS project. Examples are Burger Schaffen Wissen ("Citizens Create Knowledge”) and SenseBox. Citizens Create Knowledge is a joint project by Wissenschaft im Dialog and the Museum für Naturkunde Berlin. Its overall goal is to support CS communities by offering guidance on how to start a CS project, how to publish a CS project, how to work with volunteers to deliver best value for them, the scientific community and other local stakeholders. Citizens Create Knowledge has been running for almost ten years now (since 2013), focusing on several thematic areas e.g. CS in schools, CS in medicine and health research, CS in Berlin.

SenseBox is an ongoing initiative by the University of Münster. What started as a research project eventually evolved into a spin-off with different commercial offerings. There are now different DIY sensor toolkits for citizens (senseBox:home), schools and young researchers (senseBox:edu), and developers (senseBox:mini) - all of which can be bought online via senseBox website. According to the openSenseMap, 9551 senseBoxes are currently in use worldwide, which collectively have taken 11.2 million measurements.

The brief review above barely scratches the surface of the German CS landscape. But even with such limited scope, we hope that the reader gets an idea of how diverse the landscape is. One small discovery that we are especially excited about is the identification of the new types of initiatives not seen in Bulgaria, namely the inside-out projects and those that support others. One conclusion we can cautiously draw from this is that these initiatives are hallmarks of more mature CS landscapes that can be typically found in countries with a long history and high levels of public participation in science. Future research, whether conducted by COMPAIR or others, might want to further explore if this hypothesis has any merit. One interesting outcome of this research could be the creation of a typology of CS regimes (see recommendation eight in conclusion) and key requirements needed for their emergence e.g. level and history of public participation in science, existence of bodies or projects dealing exclusively with CS, amount of funding available for CS, total number of projects and domains covered.

Primary cluster

Stakeholder engagement

Most projects in air monitoring engaged participants through online outreach and workshops, with additional support provided in the form of training material. The renowned Sensor.Community practices the self-assembly and self-installation approach. But this doesn’t mean that interested volunteers are completely on their own if they want to deploy a sensor outside their home. Many local hubs organise open-access workshops for people who want to build their own sensors. Moreover, there is an international forum that provides support regarding sensor use and access to a large body of information on possible solutions to different technical problems.

Hardly any projects reflected on the pros and cons of different engagement tactics used. The only exception is hackAIR. The German pilot targeted potential citizen scientists online and through in person workshops. The team concluded that the degree of involvement was higher among users who attended the workshop and bought a sensor, than among those who were targeted by online means only (social media, newsletters, press releases). Why this was the case wasn’t elaborated in the report, but perhaps the reason for that is two-fold: 1) people tend to absorb new knowledge better in a physical setting, where live demos and training activities appear more accessible and easier to understand, and 2) people tend to be more motivated to carry on with a certain task if they had to purchase something to accomplish it.

Some projects prefer to mention how many sensors are deployed instead of providing information on citizen scientists involved e.g. Sensor.Community (14388), senseBox (9551).[4] The HEAL project provided even less information on the Berlin pilot, stating only that it cooperated with 10 primary schools that represented a total of 4300 pupils. One project that stands out is, again, hackAIR. It reported information on the overall number of sensors set up (800), the number of people who attended workshops (500) and contributed to the project one way or another (3000).

Participation of hard-to-reach groups in CS activities was not explicitly mentioned by any of the projects. Potentially, they could have been involved in the HEAL project, provided that the 10 participating schools have children from lower-income families, a hard to reach group we are particularly interested in engaging in COMPAIR. Their participation could also have been enabled by senseBox and Sensor.Community owing to these projects’ cooperation with primary education institutions (#Sensor2School, senseBox:edu).

hackAIR is the only project in the cluster that listed the full urban value chain among its users: citizens, local government, enterprises, scientific community and civil society organisations. The successful deployment of the quadruple helix model combined with the multi-channel engagement tactics used could explain why hackAIR benefited from contributions of 3000 people over the course of the project.

Finally, as regards the 10 principles, none of the reviewed projects acknowledged ECSA’s guidance openly. This doesn’t necessarily mean they didn’t want to follow it, it could mean they simply weren’t aware of it, or didn’t find it necessary to make a demonstrable link to it in project documentation. The fourth principle states that “citizen scientists may, if they wish, participate in multiple stages of the scientific process.” hackAIR claims, for example, that besides data collection, volunteers got involved in coding and training. In the case of BerlinAIR NO2 Atlas, in addition to data collection, participants were able to prepare and evaluate passive samplers in the laboratory. This clearly shows that projects may actually be following some or all of the 10 principles even if these are not clearly acknowledged in project deliverables.

Data collection and analysis

In terms of data captured, some projects measured only particulate matter (hackAIR), some only NO2 (BerlinAIR NO2 Atlas), some a mix of both (HEAL). A few projects added to the list atmospheric conditions like temperature, humidity and pressure (senseBox), and some went so far as to measure allergen content, precipitation and UV radiation (PolDiv).

With regards to sensors used, NO2 measurements were carried out using simple measuring tubes (passive samplers) in the HEAL project. For PM measurements, most projects offered DIY kits that could be ordered online e.g. hackAIR, senseBox, Sensor.Community. The exception was HEAL which used a low-cost, but not a DIY sensor with a light scattering property. All other gases and particles required special tools e.g. electronic pollen measuring devices, pollen traps, a CO2 monitor.

Except PolDiv, all results were presented in some form, either on a map, in a report, or both. There is a clear preference to use online maps to display CS data, although in the HEAL project, the findings are summarised only in a report.


Two projects whose technical credentials impressed us the most are Sensor.Community and enviroCar. Sensor.Community developed a standard sensor kit (Node MCU SDS011) that has been widely used by individuals and projects around the world. The kit is made of universal components like an electronic module for WiFi communication, fine dust sensor, temperature, humidity and pressure sensor, cables, and plastic hydraulic elbows for weather protection. This means users can build a relatively light and small device at an affordable price (about 50 euros). Raw data from these sensors can be transferred to an online map where value readings of particulate matter and other parameters are displayed for the last 24 hours. While there are definitely many reasons for its success, this balance between cost-effectiveness and ease-of-use that Sensor.Community has managed to strike must be a factor in its worldwide growth over the years.

enviroCar earned plaudits from us because of its focus on open standards. The project is completely open source. All of its components are available on Github. Users can avail of the Web API to create new products and services e.g. maps, statistical analysis. Gathered data is publicly available as JSON and linked data, which means it can easily be integrated into any service that works with these standards.

With regard to behavioural change, a project that drew our attention is hackAIR, not necessarily because of the scale of its impact on individuals, but because of the effort that was made to measure it. The study in Berlin implemented a sophisticated Modular Behavioural Analysis that consisted of semi-structured interviews with hackAIR users following a predefined interview guide. While respondents did not always state a direct impact of hackAIR on their knowledge of air pollution, they did mention that working with CS tools was a stepping stone to a better engagement with the issue. Participants reported paying more attention to air pollution whenever it appeared in the news, for example. Hence, because hackAIR opened a door for them, or supported an already existing interest, they reported to have gained more knowledge on the subject by the end of the project. Respondents did not report many changes in terms of preventive behaviours e.g. avoiding going outside, keeping one’s windows closed, wearing a mask. But some did carry on a pre-existing protective behaviour (self-care), such as avoiding busy roads.

When it comes to urban policy making, no project reported any significant impact in this area. hackAIR even openly acknowledged that political impact was rather limited as there were no specific activities or tools organised to evoke direct policy impact. If we shift focus to education policy, perhaps one project that we could highlight is senseBox. According to press reports, it appears that the Ministry of Education used project results to coordinate learning opportunities for students.[5]

Secondary cluster

Highlights from other initiatives

A project with a well-thought-out engagement approach is Citiclops. Although it deals with water quality, what stands out is their step-wise process to increase the level of maturity of stakeholder engagement. At low maturity, participants are surveyed to get a better sense of their motivations and needs. At high maturity, participants take ownership of results, to the point where they may even co-manage a CS lab alongside original founders. The five steps are:

  • Understanding and engaging stakeholders

  • Getting started with stakeholders

  • Developing a participatory science approach

  • Helping stakeholders to act as advisors

  • Developing co-management approaches

Citiclops did not refer to the 10 principles directly, but many of them were clearly incorporated into the project's modus operandi. In the early stages, Citclops' researchers consulted stakeholder communities as they planned, designed and started to implement the citizens' observatory. As Citclops evolved, stakeholders took a more active role, participating in the observatory's structure and management, and sometimes negotiating with Citiclops's partners to ensure their specific goals and values were represented. At full maturity, Citclops shared management between project partners and stakeholders, and in some cases transferred management completely to local communities, with observatory's managers only providing advice and consultation. Presumably, this is the kind of maturity trajectory COMPAIR should be aiming at, one that starts with some basic engagement and culminates in a setup whereby local communities manage a CS lab first in cooperation with and later with minimal intervention from project partners.

One thing that stands out in the secondary cluster is immensely high participation rates (i.e. number of volunteers) among some projects. Clear leaders in this regard are biodiversity and water related projects like NaturGucker (111.395), Muckenatlas (29.000), Plastik Pirates (15.000), BeachExplorer (4099), ArtenFinder (3000), Ornitho (1300), My Ocean Sampling Day (1000).

In general, we noticed a clear tendency to use digital tools for data capture. Most projects introduced apps to collect information (on animal species, soil quality, water quality etc.), some both apps and websites (e.g. NaturGucker, BeachExplorer, ArtenFinder) and some websites only (Stadwild Tiere Berlin). It’s worth pointing out that not everything can be captured digitally. In some cases, the use of ‘manual’ tools is often the only way to obtain required information. For instance, to collect insect samples, the InsektenMobil project used rooftop nets on cars; to collect mosquito samples, the Muckenatlas project asked participants to catch, freeze and send dead mosquitos to the lab; to collect water plastic, participants in the Plastik Pirates project used sampling nets and sieves to retrieve plastic pieces from water bodies.

As with data capture, there is a clear preference for online tools when it comes to results presentation. Most projects offer map-based visualisations of their findings. Only a couple of the reviewed initiatives use publications as the only method for dissemination (Tauchen für Naturschut, Fledermausforscher in Berlin).

With regards to technical impact, some projects demonstrate a very strong focus on open innovation. A good example would be the now familiar Citclops that developed its web portals with open principles in mind. The idea was that by using standards like OGC and SensorML, by enabling data sharing with GEOSS and by including semantic aspects and linked data, the project would be able to create really advanced means of information delivery to generate powerful insights for stakeholders.

In terms of behavioural change, projects often claim that participation in CS can lead to improved knowledge and awareness among participants, but only one project (My Ocean Sampling Day) actually made an effort to survey volunteers and share the results publicly. It found that 83% of those surveyed agreed that participation made them feel more engaged with ocean issues. Interestingly, some citizen scientists thought that My OSD app and sampling procedures were too complicated. The project addressed these complaints through personal communication with participants and by improving the usability of the app. This story is an important reminder to COMPAIR and indeed any other CS project that all protocols and tools should ideally be tested internally over several iterations before they are made available to the public. Then, when data collection starts, both pilot leads and technical teams should be on standby to react quickly to user complaints/suggestions while field activities take place. A more comprehensive survey should be launched ex-post, focusing not only on functionalities and methods, but also people’s experience with CS, both positive and negative.

Another interesting project worth mentioning with regards to behavioural change is Netatmo. It’s a French company that creates IoT products for consumers. Their Smart Home Weather Station (costs between 170-300 euros) has been used worldwide, while in Berlin there were at least 100 markers representing each owner that wished to display their data on a map. Netatmo doesn't stylise itself as a CS project. But many of Netatmo’s customers inadvertently become citizen scientists as they collect air quality data and other atmospheric information (temperature, humidity, pressure, CO2 etc.) through their weather stations.[6] This could be an alternative route to CS for people who don't want to go through all the protocols, preferring the convenience of an informal, no-strings-attached crowdsourcing approach instead. For some consumers, products like Smart Home Weather Station could be a stepping stone to the world of CS.

Finally, when it comes to policy impact, many projects are clearly thinking about public policies and legislation they can influence through their results, while a few have already claimed some early successes. For example, data collected by Muckenatlas contributes to mosquito research and public and animal health in Germany. The project’s database is open to the scientific community and political stakeholders to facilitate risk assessments and modelling as to where to expect mosquito-borne diseases in the future and how best to manage them. By collecting data on cycling accidents in Berlin, SimRa plans to influence changes in traffic signalling plans so that cycling can become safer and more attractive for city residents. In the FLOW project, the water body data collected by volunteers is incorporated into ecotoxicological and ecological studies to serve as a basis for local and regional strategies for water protection. And thanks to the Tauchen für Naturschut project, the idea of ​​nature-conservation diving was proposed for implementation in the Mecklenburg Lake District.


In the 29-strong German sample we found initiatives that originated in Germany but have since spread to other countries (the so-called ‘inside-out’ initiatives), and initiatives that completed the opposite journey i.e. they arrived in the country as an extension of an international project (outside-in initiatives). Many projects are initiated, funded and managed by domestic stakeholders, and then there are ‘supporters’ i.e. projects that support the growth of the CS community without running any CS activities themselves. Projects that monitored air pollution and traffic did offer some training and guidance to participants, but the effort was mainly oriented toward technical skills needed to successfully operate a DIY sensor. Where attempts were made to measure behavioural change, the most commonly reported impact was increased knowledge and interest in air pollution. There was little impact on policy in the air cluster, but this has been compensated for by considerable impact on technology, delivered mainly, but not exclusively, by two inside-out projects Sensor.Community and senseBox.


[1] The names of schools were anonymised in the report, however all ten were identified as being at a busy location and covered the areas of Neukölln, Mitte, Tempelhof-Schöneberg, Steglitz-Zehlendorf, and Friedrichshain-Kreuzberg. [2] [3] [4] These are global figures. [5] [6] See for example a research analysis of Netatmo’s data Fenner, D., Meier, F., Bechtel, B., Otto, M., & Scherer, D. (2017). Intra and inter 'local climate zone' variability of air temperature as observed by crowdsourced citizen weather stations in Berlin, Germany. Meteorologische Zeitschrift, 26(5), 525-547. doi:10.1127/metz/2017/0861



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