We all know the great benefits and potential of crowd-sourced observations for monitoring environmental issues.

What is also true is that the power, benefits as well as limitations of citizen science based data is still being researched, while methods are being investigated for determining the data quality of observations or inversely, the data uncertainties.

When investigating the existing systems deployed across our Greek pilot site, the Kifisos river in Attica, Greece, we were amazed by the fact that – besides weather stations – there were no monitoring systems installed by any authority or organisation.

Thus, the partnership and the Greek pilot cluster team decided to install a few in-situ sensors at dedicated points within the river flow in order to have these as benchmarking points so as to calibrate and validate the citizens’ observations.

During the week 25-29 September 2017, the ICCS team, coordinated by Dr Antreas Kallioras, installed five in-situ sensors measuring the water level in the river: three of them were piezoelectric sensors (LEV 1 model) and two were radar-based (Radar RLS).

The latter were installed close to bridges were the river flow is fairly a straight line for some tens of meters, a prerequisite for getting valid information.

The team faced several challenges, including constraints to access the bridge while traffic was flowing and to ensure that the sensors are not visible and thus vulnerable to damage or theft.

The sensors have embedded data-loggers where data is already being logged, while later this autumn, 3G cards will be installed for allowing back-end connectivity with the Scent harmonisation platform and also remote configuration.

The ICCS team had to hurry to make the installations before the wet season starts, in order to use data collected also for flood models data calibration.

Stay tuned for our followup articles with the first insights on data patterns and comparisons with crowd-sourced observations in the next semester!

Scent had a dynamic presence at GEO Week 2017, held in Washington, D.C. on 23rd-27th October 2017. The event included the 14th Plenary Session of the Group on Earth Observations (GEO), an exhibition as well as a number of side events.

Scent participated with both a poster in the EU booth and a presentation at the side event “The role of Citizen Observatories and Crowdsourcing Community in GEOSS”.

Lightning talks were given by Scent and fellow CO projects Humanitarian OpenStreetMap, GEO BON, Ground Truth 2.0 and LandSense. A discussion session was also held on the subject of “Tools, Best Practices, and Standards for Utilizing Citizen Science for GEOSS”.

The dominant subject in the discussion was the balance between the respect of the citizen’s privacy and the reuse/repurpose of the data. The different regulations between countries, the lack of licensing and documentation of collected datasets, the need to notify contributors in cases of reuse of data as well as the participation of minors in data collection were among the raised concerns.

Furthermore, it was discussed that the Data Quality (DQ) Control needed for crowdsourced data is not that different to the DQ control needed when publishing scientific data. It was agreed that there are best practices in place that ensure high DQ and that most projects are making great efforts to take the practices into consideration. What is still missing is the appropriate documentation to show how each project incorporates them and their efficiency.

In addition, the issue of user engagement was discussed. It has now been established that in order to engage citizens and to get them to make continuous contributions, there must be some recognition of their efforts. People want something in return for their contributions. The most meaningful way to recognise their contributions is to make the contributions part of the established policies. This raises the need to train the policy makers to let go of some of their control, listen to the citizens and incorporate some of their proposals.

Last but not least, the issue about whether something really belongs to Citizen Science and whether it should be open and accessible to all was discussed. Concerns were raised about the fact that Citizen Science is introduced to many scientific areas where it might not be fit for purpose. What is more, while it was recognised that the value of Citizen Science lies within the opportunity to reuse and compare collected data, it was mentioned that some data should not be made easily accessible. Making the locations of endangered species available in real time and thus easily located by hunters was the example given to support this view.

In conclusion, it has become obvious that the exponential growth in the use of Citizen Science has brought the GEO community to a critical point where proper standards and best practices should be established in order to support the growth and the community.

As the Scent pilot activities are being planned, we are interested in drones and in their role in the pilots. We turn to Dr Paolo Paron, Senior Lecturer in the Department of Water Science and Engineering at IHE Delft Institute for Water Education based in Delft, the Netherlands. Paolo is a drone expert with significant experience in the field. This article focuses on Paolo’s insights into the world of drones and their use in Scent, and the importance of citizens’ contributions. First, a few words about Paolo.

Behind the scenes with Paolo Paron

Introducing Paolo | Paolo is a trained geologist with an MSc degree in Geology and a PhD in Fluvial Geomorphology from the University of Rome, Italy. He has also been a long-term visiting researcher at the Department of Geography of the University of Oxford, UK, and has worked with Charles Darwin University in the Northern Territory in Australia.

Paolo joined IHE Delft in 2011. He is part of the Hydraulic Engineering and River Basin Development chair group within the institute’s Department of Water Science and Engineering. His core areas of expertise are Earth Science and Remote Sensing. Before joining IHE Delft, Paolo worked as a consultant for the United Nations and other organisations in Kenya where he lived for six years. Paolo’s educational background is thus in geology, but he has also built on his expertise in the field of remote sensing continuously for a number of years. In his role as a senior lecturer at IHE Delft, Paolo is able to combine these two areas.

From kites to drones | When Paolo arrived at IHE Delft in 2011, he started to use kites for aerial photography along the windy Dutch coastline. By walking along the coast flying a kite with a camera attached to it, he photographed and mapped changes in the local dunes. About four years ago, Paolo started to use unmanned aerial vehicles (UAVs), commonly known as drones, instead of kites. He has since been following the rapid development of the drone industry closely and acquired first-hand experience of using different models of drones and of practicing various techniques.

The rise of the drone | Drones became a widely available commercial product and a trending Christmas present a couple of years ago. The mainstreaming of drones has helped to shake off the primarily military connotation which used to be associated with the name. The development of the commercial drone business for all civil applications, recreational and professional, has led to people not associating the name with military use anymore.

Some features of commercial and professional drones:

Paolo lists three key elements to consider if you are planning to buy a drone:

• The flying platform: how portable the drone is, how long it can fly for, what the environmental conditions it can sustain are etc.;
• The camera and add-ons: nowadays drones normally have a camera on board already, but you can also add one oneself, or sensors that detect e.g. temperature or magnetic fields;
• The software: most modern drones, especially the commercial ones, are now guided by an app that one can download to a tablet or phone. Thanks to recent software developments, safety aspects have improved significantly.

Before modern apps were introduced, people flew drones using very basic apps with no safety measures embedded. Before that, when there were no apps at all, people used only a remote control and a small monitor indicating where the drones were flying. Today’s safety measures are based on a combination of advanced software and hardware components in the drones themselves. The latest versions are very user friendly and the commands and controls of the user interfaces (UIs) are clear and intuitive. In the past, a drone operator needed a lot of prior knowledge before flying a drone. Today the UI icons, terms, camera settings and the displayed flying path are so intuitive that even a first-time recreational drone flyer can manage them without needing to worry about crashing or losing the drone.

Drones at IHE Delft | IHE Delft has three in-house multirotor drones. Two of them are commercial models (DJI Phantom 3 Pro and 4 Pro) and one is a professional model (a Cortex octocopter by CopterSquad). In addition, the institute has one fixed-wing model drone (a twin engine Explorer model by Bormatech), the shape of which resembles a plane, and one more drone (DJI Phantom 4 Advanced) brought in by a colleague entering the field, which brings IHE Delft’s total number of drones up to five.

Drone usage | When asked about what they think drones are used for outside the military context, most people will say aerial photography and videography for recreational purposes. Taking photos and filming videos using low-flying drones have indeed become very popular and enable you to capture more refined details and small objects in high resolution than using planes or satellites for the same purpose. Cameras mounted on drones nowadays tend to use the latest 4k technology, allowing for the high-quality footage to be used for both recreational and professional purposes. 4k refers to the number of pixels per frame and is an expression of the resolution of images and videos, also used in the TV industry. The next generation technology, 6k, is currently only found in the latest models of video cameras for professionals, but already advertised for some drone types. Thanks to the rapid evolution of the miniaturisation of hardware, 6k is expected to be available also in commercial drones soon (see, for example, the latest camera developed for drones, the DJI Zenmuse X7).

Drone applications are, however, by no means limited to photography and filming. Drones are constantly adapted for new, innovative areas of application, some better known than others. The big driver of the development of the drone industry is agriculture – more specifically precision agriculture. More and more farmers with large-scale farms in both Western and developing countries request the services of drone operators. They hire drone operators to fly drones over their cultivated lands, for example in order to identify areas in which their crops don’t grow properly. The reasons may be linked to different factors related to nutrients in the soil, irrigation heterogeneity, differences in fertiliser distribution etc. Providing farmers with a map telling them where their crops don’t grow properly allows them to go out in the field with a tractor and fertilise only those specific areas or change their irrigation schemes according to their needs.

Some estimates suggest that 100,000 jobs will be created in the drone industry in agriculture in the US alone by 2020. The application of drones into precision agriculture is estimated to grow to a business of approx. $80 billion by the same year (source: Aviation Week).

A widespread drone usage that goes beyond precision farming is deriving digital elevation models (DEMs), i.e. digital representations of the topography of the area that a drone is flying over. DEMs are very valuable for the professional industry and various other fields in that they allow for surveying, monitoring and mapping changes in the topography, the vegetation and the landscape in general. By repeating a flight over a certain area over a period of time, it is possible to identify changes taking place in a particular area.

The role of drones in Scent

In Scent, drones will play a central role in two types of activities in the planned large-scale demonstrations. These activities, flood modelling and monitoring land cover changes, will be described in the following.

Contributing to flood modelling in two different ways:

• We will fly drones over flooded areas and map out the extent of the flood waters. The aim is to fly over a flooded area soon after a flood event. As drones always carry a GPS, we will know the exact location of every single image that is taken. We can decide on a relevant flight path and programme the drone to fly over a particular stretch in order to be able to measure the extent of the flood waters along that stretch.
• We will also fly drones over predefined stretches during the dry season in order to derive digital elevation models. We want to use high resolution DEM models as input for flood modelling. To create flood models, you need both the amount of water flowing the river and the accurate topography of the flood plain, which is what the DEM provides.

Monitoring land cover changes or other environmental changes:

• We will fly drones over certain predefined areas and stitch together all the photos taken to form one large and detailed picture (an orthomosaic) of the area we fly over. By flying over the same areas repeatedly over the course of the project we will be able to accurately map the changes in land cover, whether they are natural or result from human interference. If there has been a flood, we will see the consequences of it, i.e. the impact on the crops, the natural vegetation, the infrastructure etc. in the area.

Safety first | The drones that both the citizen scientists and the researchers will be using in the Scent pilots are commercial ones. All safety measures are already in place in the software of commercial drones, and both researchers and citizen scientists can use them without risking to cause damage to themselves or to third parties. Volunteers can join the Scent movement without needing to be experienced in the use of drones.

Challenges in the pilot areas | The Scent activities will focus on two very different areas: the Danube Delta in Romania and the Kifisos in Greece. The challenges involved in each area are also very different, and we will address them through careful planning and preparation.

The Danube Delta

The Danube Delta, the second largest river Delta in Europe, is challenging as a pilot area because of its sheer size and limited accessibility. Its immense surface area stretches over thousands of square kilometres and is largely out of the range of drones. To cope with this interesting challenge, we decided to focus on a small area of interest rather than on the entire Delta. We will be able to access this area by boat only, a challenge we are looking forward to facing. When using drones in the area, we need to keep their limited battery life in mind. On days with no wind, we normally fly for 25-30 minutes at a time. In order to be able to cover a large area, we will carry several batteries, split the flying area in different portions and fly with many batteries. The Danube Delta pilot will start in summer 2018.

Kifisos

In the Kifisos area, we face two main challenges. One of them is related to the topography and the other one to the urban nature of the area. Because the area is a mountain basin, we need to plan the drone flight path carefully in order not to interfere with mountains or other high-rise obstacles. The area being largely urban means that electromagnetic disturbances need to be taken into account before flying drones over it. Flying over urban areas is always challenging as drones are connected to a remote control in the tablet or phone via a radio link, and urban areas always have telephone antennae and other electromagnetic disturbances that can interfere with the signal. Before the start of the Kifisos pilot in autumn 2018, we will assess these issues and determine up to where it is safe to fly.

These are the main challenges that we have identified so far. As with pilot studies in general, it is possible that unforeseen challenges arise once we are out in the field. If we make unexpected discoveries that may have a knock-on effect on our plans, we will be prepared to address new, interesting challenges.

Drone regulations | Europe has experienced different phases of regulation of drone use. At the beginning, there was no regulation. When regulations were introduced, they were first extremely restrictive, and they have now been relaxed in most countries. The use drones for recreational purposes outside urban areas generally doesn’t require a permit anymore, but the rules still vary from country to country, and one therefore always needs to check the latest applicable rules in the relevant country. A European Commission expert group has been established to develop and implement an EU drone policy, but no harmonised rules have been introduced at European level yet. In Scent, we need to monitor the Romanian and Greek regulations closely in order to be sure we comply with the applicable rules in these pilot countries.