Involvement of all of the imoca 60s taking part in the Barcelona World Race 2014/15 |
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The skippers of the Barcelona World Race are collaborating with the Citclops (Citizen’s Observatory for Coast and Ocean Optical Monitoring) project which is part of the 7th Framework Programme at the European Commission, the Barcelona Digital Technology Centre (BDigital) and the Fundació Navegació Oceànica Barcelona (FNOB).
The Citclops (Citizen’s Observatory for Coast and Ocean Optical Monitoring) project is based on optical monitoring of the transparency, colour and fluorescence of the surface of the sea, to determine quality and, above all, the effects on plankton.
This process involves all of the IMOCA 60s taking part in the Barcelona World Race 2014/15 and is headed up by the Institute of Sea Sciences (ICM), the Barcelona Digital Technology Centre Foundation (BDigital) and the Citclops/ 7th Framework Programme at the European Commission.
The Citclops (Citizen’s Observatory for Coast and Ocean Optical Monitoring) project is based on optical monitoring of the transparency, colour and fluorescence of the surface of the sea, to determine quality and, above all, the effects on plankton.
This process involves all of the IMOCA 60s taking part in the Barcelona World Race 2014/15 and is headed up by the Institute of Sea Sciences (ICM), the Barcelona Digital Technology Centre Foundation (BDigital) and the Citclops/ 7th Framework Programme at the European Commission.
The Citclops-citizen water monitoring app
 Android
Cameras fitted to the boats will record data in areas for where they is currently a lack of information. In addition, skippers will use the Citclops - Citizen water monitoring app, that is available for Android and iOS. This app allows you being more informed about the sea, being environmentally active doing coast-watching and enjoying more your favorite water activities. If you want to know the making of the app, you can visit this section of the Citclops website.
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What is the colour of the sea?
You never think about it. Dr. Marcel Wernand, physical oceanographer at NIOZ, tells about his research. He shows many kinds of differently coloured seas and explains its cause.
The colour of the water, together with its clarity, is one of the most apparent characteristics to the human eye when natural water is observed. In general, the apparent colour is a result of substances that are either suspended or dissolved in the water column. There are three main components besides the water itself (which has a pale blue colour) affecting the water colour in natural environments:
1) Phytoplankton (microscopic algae) or chlorophyll containing particles. These organisms generally cause a green colouration of the water (due to the presence of chlorophyll within their cells), except for certain species of phytoplankton that cause a red or brown colouration.
2) Non-algal matter, such as fine soils (chalk). Its effect on the water colour will depend on the origin of the material (brownish or reddish) but in general it gives a ‘cloudy’ effect to the water.
3) Dissolved coloured matter, mainly organic compounds including humic acids and tannins that originate from many types of terrestrial and aquatic plants, and give the water a yellow to brownish colouration.
The type and mutual proportion of the concentrations of these main components determine the specific water colour, and different types of natural waters (rivers, lakes, seas and oceans) can be recognised and classified in relation to these proportions.
The colour of water has always intrigued painters, poets and people in general. Over the years, methods were described to record water colour in a thrust full manner. One of the oldest methods uses the Forel-Ule colour comparator scale. An example of the diversity in colour of natural waters seen through our eyes or by camera is given in Figure 1.
1) Phytoplankton (microscopic algae) or chlorophyll containing particles. These organisms generally cause a green colouration of the water (due to the presence of chlorophyll within their cells), except for certain species of phytoplankton that cause a red or brown colouration.
2) Non-algal matter, such as fine soils (chalk). Its effect on the water colour will depend on the origin of the material (brownish or reddish) but in general it gives a ‘cloudy’ effect to the water.
3) Dissolved coloured matter, mainly organic compounds including humic acids and tannins that originate from many types of terrestrial and aquatic plants, and give the water a yellow to brownish colouration.
The type and mutual proportion of the concentrations of these main components determine the specific water colour, and different types of natural waters (rivers, lakes, seas and oceans) can be recognised and classified in relation to these proportions.
The colour of water has always intrigued painters, poets and people in general. Over the years, methods were described to record water colour in a thrust full manner. One of the oldest methods uses the Forel-Ule colour comparator scale. An example of the diversity in colour of natural waters seen through our eyes or by camera is given in Figure 1.
Figure 1. Six differently coloured sea areas with from left to right top; Central Atlantic, Central North Sea, Coastal North Sea. From left to right bottom; Coastal North Sea during algal bloom, Wadden Sea with lots of re- suspension of sediment and a coastal outlet dominated by yellow substance. (photos: Courtesy of B. Aggenbach, A. Hommersom and M.Wernand).
Why is it important?
Next to water temperature, salinity and transparency (see Water transparency), water colour observations belong to the oldest time series of climate data. Water colour is an Essential Climate Variable (ECV) designated by the World Meteorological Organization (WMO) for which sustained and climate quality measurements are needed to track and analyze climate change. This is nowadays considered an important aspect of the science of natural-water-optics, since the colour of the ocean is determined, partly, by phytoplankton. A variation in phytoplankton abundance implies a change in the uptake of CO2, the primary greenhouse warming gas, suggesting a possible role of these organisms in the regulation of climate.
Coastal waters, rivers and lakes can vary in colour due to natural events, such as algal growth, during spring that can make the water greener. However, the colour can also be affected by human activities, for example, due to an addition of nutrients, such as phosphates and nitrates (through sewage or fertilizers), that cause phytoplankton to grow. This phenomenon is known as eutrophication. A change in water colour not only affects the aesthetics and the recreational value of a water body (generally people prefer to swim in blue-green clear waters than dark and murky waters), but could also have a harmful effect on the environment as the one caused by harmful algal blooms.
So, how do we know if coloured water is natural? A good way to start is by collecting long-term colour data along with other water quality indicators, such as transparency and fluorescence. This information can be used to determine what is happening in a water body. For example, if the water in a coastal area has been blue-green for a long period of time, a change towards a more brownish colour can indicate something is altering this environment.
Long-term monitoring of a simple attribute of water such as the apparent colour, using low-cost devices and the aid of citizens, could help detect changes taking place in aquatic environments in a rapid way, without the need of costly and time-consuming water quality analyses.
How it is measured?
Observations of the water colour date back all the way to the late 19th century, when the Forel-Ule colour comparator scale was created. This scale is composed of 21 colours, going from indigo blue to ‘cola’ brown, through blue-green, green, and yellow colours (see Figure 2). This system works well because the human eye can accurately match colours when viewed simultaneously.
Next to water temperature, salinity and transparency (see Water transparency), water colour observations belong to the oldest time series of climate data. Water colour is an Essential Climate Variable (ECV) designated by the World Meteorological Organization (WMO) for which sustained and climate quality measurements are needed to track and analyze climate change. This is nowadays considered an important aspect of the science of natural-water-optics, since the colour of the ocean is determined, partly, by phytoplankton. A variation in phytoplankton abundance implies a change in the uptake of CO2, the primary greenhouse warming gas, suggesting a possible role of these organisms in the regulation of climate.
Coastal waters, rivers and lakes can vary in colour due to natural events, such as algal growth, during spring that can make the water greener. However, the colour can also be affected by human activities, for example, due to an addition of nutrients, such as phosphates and nitrates (through sewage or fertilizers), that cause phytoplankton to grow. This phenomenon is known as eutrophication. A change in water colour not only affects the aesthetics and the recreational value of a water body (generally people prefer to swim in blue-green clear waters than dark and murky waters), but could also have a harmful effect on the environment as the one caused by harmful algal blooms.
So, how do we know if coloured water is natural? A good way to start is by collecting long-term colour data along with other water quality indicators, such as transparency and fluorescence. This information can be used to determine what is happening in a water body. For example, if the water in a coastal area has been blue-green for a long period of time, a change towards a more brownish colour can indicate something is altering this environment.
Long-term monitoring of a simple attribute of water such as the apparent colour, using low-cost devices and the aid of citizens, could help detect changes taking place in aquatic environments in a rapid way, without the need of costly and time-consuming water quality analyses.
How it is measured?
Observations of the water colour date back all the way to the late 19th century, when the Forel-Ule colour comparator scale was created. This scale is composed of 21 colours, going from indigo blue to ‘cola’ brown, through blue-green, green, and yellow colours (see Figure 2). This system works well because the human eye can accurately match colours when viewed simultaneously.
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Figure 2. Left: Secchi disk. Center: The Forel-Ule scale. Look to the Secchi disk (at ½ SD depth) and compare colours. Right: Citclops app
The colour measurement with a Forel-Ule scale should be done with a secchi disc at the moment, but methods are being developed within the Citclops project to assess the water colour without the use of a disc.
The determination of the water colour using a Forel-Ule scale can be accomplished using either a FU scale made of plastic (Figure 2) or the Citclops app for smart phones (Figure 3), as follows:
With the plastic Forel-Ule scale:
1. Slowly lower the disc into the water until it disappears from sight and note the depth. If possible this has to be done in the a shaded area.
2. Slowly raise the disc until half the Secchi depth .
3. Determine the colour of the water with the Forel Ule scale (in the shade).
4. Compare the colour observed on top of the Secchi disc, with the colours of the scale (over the white bars (see red square) in the back (see Figure 3).
5. Record the FU number.
6. Send recorded number, along with the location (GPS data if possible), date and time to: [email protected].
With the App:
1. Slowly lower the disc into the water until it disappears from sight and note the depth. If possible this has to be done in the a shaded area.
2. Slowly raise the disc until half the Secchi depth (depth recorded in step 1).
3. Determine the colour of the water with the smartphone APP (in the shade).
4. Compare the colour observed on top of the Secchi disc, with the colours of the scale (over the white bars (see red square) in the back (see Figure 3).
5. Take a picture.
6. Answer the questions asked.
7. Click send.
The determination of the water colour using a Forel-Ule scale can be accomplished using either a FU scale made of plastic (Figure 2) or the Citclops app for smart phones (Figure 3), as follows:
With the plastic Forel-Ule scale:
1. Slowly lower the disc into the water until it disappears from sight and note the depth. If possible this has to be done in the a shaded area.
2. Slowly raise the disc until half the Secchi depth .
3. Determine the colour of the water with the Forel Ule scale (in the shade).
4. Compare the colour observed on top of the Secchi disc, with the colours of the scale (over the white bars (see red square) in the back (see Figure 3).
5. Record the FU number.
6. Send recorded number, along with the location (GPS data if possible), date and time to: [email protected].
With the App:
1. Slowly lower the disc into the water until it disappears from sight and note the depth. If possible this has to be done in the a shaded area.
2. Slowly raise the disc until half the Secchi depth (depth recorded in step 1).
3. Determine the colour of the water with the smartphone APP (in the shade).
4. Compare the colour observed on top of the Secchi disc, with the colours of the scale (over the white bars (see red square) in the back (see Figure 3).
5. Take a picture.
6. Answer the questions asked.
7. Click send.
Figure 3. The Forel-Ule smartphone App. Look to the Secchi disk (at ½ SD depth) and compare colours.
Some natural phenomena can change water colour but it does not necessarily mean that the water is of bad quality. The different colour numbers correspond mainly to these types of water bodies:
- Indigo blue to greenish blue with high light penetration (1-5 FU scale). These waters have often low nutrient levels and low production of biomass. The colour is dominated by microscopic algae (phytoplankton).
- Greenish blue to bluish green (6-9 FU scale). The colour is still dominated by algae, but also increased dissolved matter and some sediment may be present. Typical for areas towards the open sea.
- Greenish (10-13 FU scale). Often coastal waters which usually display increased nutrient and phytoplankton levels, but also contain minerals and dissolved organic material.
- Greenish brown to brownish green (14-17 FU scale). Usually with high nutrient and phytoplankton concentrations, but also increased sediment and dissolved organic matter. Typical for near-shore areas and tidal flats.
- Brownish green to cola brown (18-21 FU scale). Waters with an extremely high concentration of humic acids, which are typical for rivers and estuaries.
