Within the United Nations Sustainable Development 2030 agenda, sustainable growth in the marine and maritime sector needs sea water quality monitoring. This is a very demanding and expensive task which results in the sea being largely undersampled. MaDCrow is a research and development project supported by the European Regional Development Fund, that involves citizens as data collectors while aiming to improve public environmental awareness and participation in scientific research. Its goal is to create an innovative technological infrastructure for real-time acquisition, integration and access of data, thus generating knowledge on sea water quality and marine ecosystem of the Gulf of Trieste. Data acquisition is based on an autonomous and removable device, developed within the project, that can be deployed on any small size sailing boat, recreational vessel, or fishing boat. The device holds low-cost sensors to measure pH, temperature, dissolved oxygen and salinity and the hardware and software to acquire, georeference and transmit the environmental data without interfering with the activities of the boats. In this work we analyze the use, capabilities and advantages of low-cost sensors but also their limitations, comparing, with a special focus on pH, their performances with those of the traditional ones. Applying the paradigm in a highly anthropized area such as the Gulf of Trieste, which is characterized also by a very high spatial and temporal variability of environments, we point out that this new approach allows to monitor sea water quality and highlight local anomalies with a resolution and spatial and temporal coverage that was not achievable with previous procedures, but yet at very low costs. Once received, data are then processed and submitted to a mediation flow that contextualizes and disseminates them for public use on a website. The final products have been customized to reach stakeholders such as tourists, fishermen and policy makers. The availability of information understandable to everyone, while fostering environmental awareness, stimulates, at the same time, involvement and participation of citizen scientists in the initiative. In the future, while committing to enlarge the number of participants, we will extend the analysis also toward other types of sensors.

Marine life can be severely affected by anthropogenic underwater noise. This latter increased proportionally to the rise of human activities such as maritime traffic, marine civil engineering works, oil- and gas-related activities or offshore wind farms; so much so that, currently, it can be considered a threat to the environment. Assessing underwater noise requires quite some investments both in personnel and instrumentation. If this is affordable by several governmental and scientific organizations, this cannot be extended straightforwardly to all research initiatives or to developing countries. In addition, time and geographic coverage of monitoring can also be significantly limited by the costs of multiple installations. We explore the possibility to use a solution based on off-the-shelf and low-cost technologies combined with a scalable infrastructure developed with open-source tools only. The perspective to avoid proprietary solutions allows great flexibility in extending the current paradigm toward real-time transmission, processing, and web-based data access. Our solution has been deployed at sea in November 2020 and is providing data continuously ever since. First results from the analysis of these data allowed us to highlight several interesting abiotic and anthropogenic temporal patterns.

Marine research is as important as very demanding since it requires expensive infrastructures and resources. Scientific institutions, on the contrary, have very limited funding so that the seas remain, still, mostly unexplored. Another serious concern is that society at large often resonates with fake news, while scientists sometimes tend to bias research with their backgrounds and paradigms. We think that all these issues can be addressed opening the process of knowledge building to the questions and needs of stakeholders and laypeople. The MaDCrow project proposed and tested several paths to attain these goals.

<p>The Oceans cover 70% of the surface of our planet and contain 99% of the living space on the planet. Surveying the blue planet  is a very demanding and expensive activity since requires large infrastructures and trained personnels. Research  institutions, on the contrary, have very limited funding to perform their studies  so that the seas remain, still, mostly unexplored. This urges for  a bold step towards a new paradigm for marine data acquisition. MaDCrow (Marine Data Crowdsourcing) is a marine technology research and development project co-funded by the European Regional Development Fund (ERDF), aiming  to create an innovative technological infrastructure for the acquisition, integration and dissemination of data on the marine ecosystem. This is coupled with the goal to increase  public awareness of environmental issues and in particular of climate changes as drawn within goal 13.1 of the UN Sustainable Development Goals. MaDCrow sensors acquire Temperature, Salinity, pH and Oxygen data in real time. These are placed in ad hoc housing  that can be installed  on citizen’s  vessels . Data acquired are transmitted onshore, stored, processed and integrated with other information sources in order to provide end-users with an App- or web-site-based  clear picture of the status of the marine environment to address relevant social questions (e.g.: where is a good place to swim?; is there an oil spill?; are the seawater conditions good for aquaculture and fishery?) The main idea behind the project is to bridge the gaps among three actors who are mutually interdependent, namely: (I) Researchers, (II) Policy makers and (III) and the Citizens.</p><p>From the point of view of the scientific community, data acquisition by volunteers is a mechanism that has many advantages. It keeps costs low while at the same time generates large quantities of information. We will discuss the pros and the cons of MaDCrow approach and the future development of this multi-stakeholder initiative.</p>