sailors to participate in global scientific survey

Odontella

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The Secchi Disk citizen science study is now in it's 7th year and I wanted to bring you an update to show how the study is progressing through sailors taking part.

The best way is by the project map and this image, taken today, clearly shows the global coverage the study is achieving.

Secchi Data coverage 2019_YBW.jpg

While you cannot zoom into the map I have attached you will see that the intensity of data (as well as the coverage) is quite great in places if you visit the data map on the study's website.

You can read the study's first paper, with seafarers as the first authors, in the journal PLOS ONE

The other purpose of this e-mail is to ask for your continuing help to promote the study to more sailors that might like to get involved in science as they sail, whether that is just by word of mouth, a poster on a club notice board, or in literature, such as in harbour and marina guides. Free to use resources are available from the Press Releases, Images and Videos tab on the Secchi Disk study's website (direct link to folder and posters can be obtained from this link).

Thank you to everyone taking part.
 
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Odontella

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Happy New Year to everyone from the Secchi Disk study.

The Secchi Disk study went from strength to strength in 2019 as more and more sailors around the world became Citizen Scientists and started collecting data on the phytoplankton. You can see the extent from the study's interactive Data Map (a screenshot as of today is given below).

You can read a recentIntroduction To The Study written by some enthusiastic marine graduates who have started a blog called The Marine Diaries or, watch the short introductory film below.

We post monthly updates on the study's Facebook page: /SecchiDisk where we have just posted the round-up for 2019.

Of course, thank you to everyone taking part already. To others of you out on the sea in 2020, we'd love you to join the study this year to help it grow even bigger as we enter our 8th year.

The Secchi Disk study is great for children although it will engage all ages with fun, hands on marine science to hopefully, inspire and educate while increasing our knowledge of the sea.

Happy New Year to you all.

Screen Shot 2020-01-05 at 15.11.21.png



 
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Odontella

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It's been a while since i last posted news from the Secchi Disk study.

But the Secchi Disk study is still going strongly thanks to sailors' data collection.

Today, the study published its second paper in the journal Nature Scientific Reports.

You can read the article HERE or by using this link https://rdcu.be/cqKH0. (Please share this publication.)

The article is Open Access and so it is free to read, download and print.

The title of the study is: Citizens and scientists collect comparable oceanographic data: measurements of ocean transparency from the Secchi Disk study and science programmes.

Along with the first publication (available here: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0186092) this new study demonstrates that the data collected by sailors for the Secchi Disk study is reliable and so it can be scientifically useful, i.e. it can be used to address scientific questions, and as such these two papers together, were important milestones for the study.

We would like to thank the Whirlwind Charitable Trust for funding the costs of Open Access publication.

And of course, huge thanks to all the participants in this ongoing study of the oceans' phytoplankton. Without your data collected while sailing, there would be no publication.

Best Wishes to everyone.
 

Odontella

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I am just returning ti this post because Sail_World Cruising have given the Secchi Disk study a great write-up today.

You can read the Sail-World article here: Perfect - the Secchi Disk Study enters its tenth year, thanks to sailors.

The Study has become what I hoped for at the outset thanks to sailors' participation, and other seafarers, such as kayakers, anglers etc.

The study can still get much bigger and much better however, so why not take part and help it to grow if you are not taking part already?

Best Wishes

Data Map 2_2022.jpg
 

Odontella

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Hi

As a New Year approaches why not join the Secchi Disk study; the study grows every year through sailors' participation as it continues to measure the oceans' phytoplankton.

The Secchi Disk study had a great birthday write-up in Yachting World this year to celebrate the commencement of the study's 10th year. The article by Yachting World journalist James Devoy also introduced other Citizen Science projects you can take part in when sailing:

Citizen science on a yacht – how you can help effect change

Thank you to everyone who is taking part already in the Secchi Disk study.

(You can learn more about the study at the study's website and in this video.)

Best wishes for your sailing in 2023.

The Secchi Disk study map at the end of 2022

Screen Shot 2022-12-27 at 12.25.49.png
 

Odontella

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Happy New Year to everyone.

Why not make a New Year’s resolution to join the Secchi Disk study and take part in Citizen Science as you sail?

2024 will be the Study’s 12th year.

As you can see from the map of data collected by sailors the study continues to grow; it is now the largest citizen science study of the ocean’s phytoplankton helping us to understand the base of the marine food chain.

The study has grown particularly fast in the last years in high latitudes as more and more expedition cruise companies are including the study as part of their guest experience programme. Guests' participation, simply by lowering a white disk into the sea and measuring the opacity, is a gateway to conversations about the marine ecosystem beyond the usually, noticed megafauna, making a difference to guests' appreciation of the marine world.

in 2024 the Oyster World Rally, a 16-month circumnavigation, will also include the Secchi Disk study as an activity. Through the participation of crews we will be able to conduct some useful experiments on individual variability as well as collect important data on in situ phytoplankton abundance that will help with satellite measurements of ocean colour. Individuals' measurement variability in citizen science studies is difficult to measure as it requires the same measurement to be taken at the same place and similar time. We hope to be able to achieve this by several crew members taking repeat measurements.

Why not join the Secchi Disk study and help it grow bigger in 2024 or, if participation is not for you this coming year, help us to promote the study and increase participation by telling friends and encouraging them to take part in some very simple citizen science while at sea.

Best wishes for your sailing in 2024

The Secchi Disk study

Screen Shot 2023-12-26 at 11.35.38.png
 

Odontella

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Another year has passed and so time to wish everyone a Happy New year and to once again, raise awareness of the Secchi Disk study - it is still running.

Why not make a New Year's resolution to take part in 2025 and beyond?

The study is not only about data collection, it's a great way to engage with marine biology for all the family and provide an insight into the marine food chain. As Susie Goodall wrote in her diary as she sailed across the Atlantic: "About half way across from Antigua the water very dramatically changed colour and [Secchi Depth] readings went from 50/60m down to 20 in the space of a couple of days and I then had marine life with me again".

Here is a great article by a sailing family (Larissa Clark and Duncan Copeland and their children) on their Beneteau 50 Celebration yacht Freeranger in Currents the magazine of the Bluewater Cruising Association.

In 2025 the study enters its 13th year having begun in 2013. The data map below shows just how much the study has grown through the participation of sailors.

Originally, the study was launched to engage with sailors, divers, fishers. The study soon covered every ocean and we had pioneering data collected from places like the Northwest Passage. Now, the Secchi Disk study has been embraced by the expedition cruise industry too as a science and outreach tool and, as a result, we have the largest in-situ database of measurements from the Antarctic and Arctic regions, which will become a useful scientific resource as the data accumulates over future years. The results from the study that we have published so far in PLoS One and Nature Scientific Reports show the value of the citizen science data.

If you you take part already, THANK YOU. If you decide to join in in 2025, THANK YOU. But even if you decide not to join in, we'd still be grateful if you would help us to grow the study by telling other sailors. The study has no funding as it is run by two independent marine scientists and so we rely upon word of mouth. As a result, we are really appreciative of the support we get from organisations such as Noonsite. Thank you :)

Happy New Year and fair winds in 2025.

The Secchi Disk study is a UK-Registered charity.

Screen Shot 2024-12-31 at 14.09.07.png
 
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Odontella

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Apologies to bump this so soon, but I just wanted to share the following with everyone as it is 'hot off the press' today and represents an important milestone.

The research published in the following Open Access paper (see link below) is the first, international, 3rd party publication to use the Secchi Disk study citizen science data set of phytoplankton measurements collected mainly, by sailors.

(The Secchi Disk study is thanked in the acknowledgements)

An application of 1D convolution and deep learning to remote sensing modelling of Secchi depth in the northern Adriatic Sea

Importantly and reassuringly, the above study also says: "statistical analysis shows no deviation of the measurements performed by citizens in comparison to the official measurements”. While that is the same conclusion we came to in our own published study in Nature Scientific Reports, it is nice to see it verified independently.

Several organisations have requested the data set over the last 2-3 years but the time to publication is slow. The above paper is an important milestone.

I hope you see this as a ‘validation' of the study and a scientific 'thanks’ to anyone reading this who is participating and collecting data. To everyone else, why not join in?
 
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viago

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I wouldn't be quite so cynical as some about taking part...

Plymouth University is a world renowned centre for Oceanographic research and the fact that they are going to use data from private individuals is irrelevant for at least a couple of reasons. Firstly they will probably have done some research to show how many errors there are from 'Jo publics' use of the home made measuring device and the results will take this into account. Secondly there are other areas of scientific research that use the public to good effect. Bird counts and astronomy use thousands and thousands of 'enthusiasts' to gather data.

If one unknown and unqualified person writes a scientific paper it will be hard for them to be taken seriously but that's not what is happening here.

You don't need a phone signal to gather the data. If you are mid ocean the iphone waits until you are next in range and asks permission to dump the data back to the university.

They appear to want data from everywhere except estuaries. Why not give it a go. I don't fancy stopping mid ocean every day to get a reading but if you are becalmed one day you could take a few. This sort if research relies on many thousands of readings over a long time to look for trends.

no less than i would expect from you.
 

viago

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Another year has passed and so time to wish everyone a Happy New year and to once again, raise awareness of the Secchi Disk study - it is still running.

Why not make a New Year's resolution to take part in 2025 and beyond?

The study is not only about data collection, it's a great way to engage with marine biology for all the family and provide an insight into the marine food chain. As Susie Goodall wrote in her diary as she sailed across the Atlantic: "About half way across from Antigua the water very dramatically changed colour and [Secchi Depth] readings went from 50/60m down to 20 in the space of a couple of days and I then had marine life with me again".

Here is a great article by a sailing family (Larissa Clark and Duncan Copeland and their children) on their Beneteau 50 Celebration yacht Freeranger in Currents the magazine of the Bluewater Cruising Association.

In 2025 the study enters its 13th year having begun in 2013. The data map below shows just how much the study has grown through the participation of sailors.

Originally, the study was launched to engage with sailors, divers, fishers. The study soon covered every ocean and we had pioneering data collected from places like the Northwest Passage. Now, the Secchi Disk study has been embraced by the expedition cruise industry too as a science and outreach tool and, as a result, we have the largest in-situ database of measurements from the Antarctic and Arctic regions, which will become a useful scientific resource as the data accumulates over future years. The results from the study that we have published so far in PLoS One and Nature Scientific Reports show the value of the citizen science data.

If you you take part already, THANK YOU. If you decide to join in in 2025, THANK YOU. But even if you decide not to join in, we'd still be grateful if you would help us to grow the study by telling other sailors. The study has no funding as it is run by two independent marine scientists and so we rely upon word of mouth. As a result, we are really appreciative of the support we get from organisations such as Noonsite. Thank you :)

Happy New Year and fair winds in 2025.

The Secchi Disk study is a UK-Registered charity.

View attachment 187359

nice colourful picture mate. how's the plankton doing?
 

Odontella

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nice colourful picture mate. how's the plankton doing?


Thanks for the opportunity to reply.

The Secchi Disk study is not a fast result study at a global scale, we need many sailors and several years of data. But I'll try to answer your question at least, in part.

How is the plankton doing,? Globally we don't really know, there are lots of different results, hence trying to collect as much in situ data as possible on the phytoplankton and why I created the Secchi Disk study; in order to get sailors involved since there are more sailors at sea over more regions of the ocean than any other group, and there are certainly more sailors than scientists. Sailors, whether day sailors or cruisers also tend to sail the same areas or routes at given times of year so it should be possible to build 'local' time series. The Secchi Disk is also very simple to use and taking a measurement is not too time consuming.

Locally, if you are interested in the plankton off the UK, the plankton is moving northwards as the seas warm. It's moved northwards by over 10˚ latitude over the last 70 years. The plankton underpin the whole food chain so it is also unsurprising that we are also seeing large shifts in the distributions of species higher up the food chain.

I don't know how interested you are? I could write a very long post that will never get read because its very length will be off-putting to everyone :)

However, I have written about the shifts we are seeing in the northeast Atlantic in a thread here. I think, well I hope, that you will find it interesting.

This week I also wrote a thread that explains the background to the Secchi Disk and to the Secchi Disk study, which you can read here.

After 13 years of the Secchi Disk study it is possible to see that the data sailors are collecting is good. The two research articles the Study has published (both are Open Access and so free to read or download from here and here) show that the citizen science data is comparable to that collected by both scientists and remotely by satellites measuring ocean colour. An independent study of phytoplankton in the Adriatic published this last week stated that: "statistical analysis shows no deviation of the measurements performed by citizens in comparison to the official measurements”. So I would encourage sailors to have confidence that the data they collect will be good provided it is collected following the simple instructions in the Secchi mobile application (iOS and Android).

The study is simply aimed at doing some 'good'. I created it for two principal reasons. Firstly, to collect data about arguably, the most important organisms on the planet, the phytoplankton. Secondly, to engage people of all ages more with the overlooked biology of the sea that I think can only add to our enjoyment if we understand and observe it more.

Finally, to quickly clear up two things that appeared in the thread of the first post you replied to above by member @john_morris_uk (itself in a reply to @Rossynant). Firstly, the Secchi Disk study is not affiliated with any organisation, so no longer affiliated with Plymouth University. The lead scientists are now independent researchers and the Study's overarching 'organisation' is the UK-registered charity the Secchi Disk Foundation and secondly, if I didn't think sailors could collect useful data (obviously we've seen one or two outliers) i wouldn't have started the study :) .

I hope this and other posts I've made encourage people to support the study by taking part.

Again, thank you for the opportunity to write a reply.

_DSC0298.jpg
 
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Mister E

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Thanks for the information.
Could you do a short explanation of what is required a d how you go about taking the readings please.
 

Odontella

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Thanks for the information.
Could you do a short explanation of what is required a d how you go about taking the readings please.

It's very simple. I'll explain below and instructions are also given in the free mobile application Secchi for GPS capable smartphones/tablets (nearly all modern devices) and in fact, the app doesn't allow you to enter a Secchi depth measurement until you have read the instructions :) The app is available for both iOS and Android devices.

The following may seem long-winded. But taking a Secchi depth measurement itself takes only about 5 minutes.

Firstly, you need a Secchi Disk 'apparatus'. (We can supply (see here) in return for a donation to the charity but we strongly encourage sailors to DIY as it is so simple.)

The SECCHI DISK - the DIY approach

A marine Secchi Disk is a 30 cm diameter white disk with a central hole ~M6. (If you Google 'Secchi Disk' you will find images of Secchi Disks that black and white quadrants and of a smaller size but that is the freshwater version, marine Secchi Disks are always plain white and 30 cm diameter.)

A Secchi Disk doesn’t have to be a perfect smooth-edged circle, just so long as it is plain white, 30 cm in diameter and it is as circular as you can make it, a 'good' circle.

What materials can be used?

The Secchi Disk we provide is made from 5 mm Foamex. 3 mm or 5 mm Foamex is an ideal material as it is inexpensive and can be cut easily, with a craft knife. Small pieces of Foamex can often be obtained for free from display / sign printers. Supermarkets also often have old Foamex display signs that they are happy to give away and one side is usually plain white. You can also buy Foamex from Ebay too, and some Ebay shops offer a cutting service.

Ten litre paint bucket lids are often 32 cm in diameter and are easy to trim with a craft knife or strong scissors. Paint/interior decorating shops that make up coloured paints for customers often have some spare buckets/lids.

You can also use a thin piece of marine plywood painted white, 3 mm is ideal, but note that water pressure during use will eventually delaminate the ply and deteriorate your Disk. Plywood is not the best option.

A plastic, white food preparation board is another option,

In fact, anything painted white. The only consideration is that the material should not be too buoyant.

Once you have a white Disk, drill a hole in the centre and use either a double stainless steel lifting eye bolt or more simply, just a small loop of Paracord passed through to allow a Fibreglass tape measure (or a non-stretchy rope marked in 20 cm intervals - use different colours for the 20 cm and m intervals) to be attached from one side and a 2 lb or ~ 1 kg weight from the other.

For most sailors we recommend a 50 m Fibreglass tape measure. However, if you are ocean cruising you may require a 100 m tape measure. A considerably, more expensive option that we do not supply, is to purchase a Yamayo Million Surveyors Rope MSR100 (Diameter Tapes / Surveyors Rope) spooled onto a cable tidy reel like this Cable Tidy Reel 25m Mains Hook Up Lead Wire Holder Storage Caravan Motorhome | eBay. Yamayo has distributors in various countries. The Yamayo tape is more durable than a cheap Fibreglass tape measure although it is not easy to put on the spool but, once spooled, it is easy to use. If you choose the Yamayo option mention the Secchi Disk study to Yamayo.

In most cases a 50 m tape measure will suffice. if you find you need a longer length and you only have a 50 m tape you can add a known length of rope between the tape and the Disk.

If you use a Fibreglass tape measure do not rely upon the metal attachment loop that comes with the tape as this will quickly corrode and one day your disk will descend to the depths. We double over the end and secure with a 8 mm bolt, Nylock nut and type-C washer: see the image below.

For the weight, any old lump of metal will suffice. The amount of weight you will need will depend upon the currents where you sample. A heavy link of old mooring ground chain, an old 1 kg weightlifting disk, fishing weight etc. Hang the weight underneath the disk using some Paracord.

You may also consider a short line from the tape measure to the yacht or even your wrist in case you drop the kit into the sea


HOW TO USE YOUR SECCHI DISK

1) Install the Secchi app on your mobile device.

2) Use your Secchi Disk to measure the Secchi depth.

1) Secchi depth measurements should be taken on sunny or partially sunny days.

The optimal time to take a measurement is between 10.00 hrs and 14.00 hrs.

We are interested in measurements from anywhere at sea, but especially taken further than 1 km offshore and in water greater than 25 m deep where the phytoplankton is the predominant influence upon the Secch Depth. Measurements taken in other places are not useless as they add to the database and may prove interesting to science in time.

Choose calm days with not too much current or wind drift.

Do not wear sunglasses !

ii) Start the Secchi app and record your GPS location. You now have 20 minutes to take your Secchi depth reading, after 20 minutes the GPS location times out and will need to be retaken.

Please note, if you have not used your mobile device at sea for a while it can take a couple of minutes for the device to locate enough satellites to get an accurate GPS location. At high latitudes where there are fewer satellites in orbit this can take a few minutes.

iii) Take your Secchi depth measurement.

With the sun behind you, lower the disk vertically into the sea from the shaded side of the boat and watch it descend in the water. It is important the Disk descends vertically or near vertically.

Record the depth beneath the sea surface (not the depth from the deck :) ) that the disk just disappears from sight; this is the Secchi depth. When you reach the Secchi depth it sometimes helps to raise and lower the Disk a little to get a good measurement.

Obviously, if you can see the seabed you cannot measure a Secchi depth.

iv) Enter your Secchi depth measurement into the Secchi app.

Once you have entered the Secchi depth options become available to enter a sea temperature, take a picture of anything interesting, for example lots of bird activity, surface jellyfish etc, write a text note and add your Boatname, but those 'extras' are all optional as we are interested primarily, in the Secchi depth..

v) Submit your data to the Pending submissions page of the Secchi app.

The Secchi app will store all the measurements you take at sea until you get a data or wifi connection. You can then submit your data. The app does not automatically submit data as we do not want to incur roaming charges for participants - you choose when and how to finally submit your data to the database.

vi) Upon your very first submission you will be asked to fetch a Unique user ID. This is now your permanent user id and it will be saved in the Secchi app.


For your assurance, all data is anonymous. We do not collect any personal data. Your User ID is unique and we cannot associate it with a person.

The opportunity to add a Boatname is simply if you want to personalise your data on the global map, it is optional. Most people do add their Boatname.

All data is freely accessible on the global data map. You can search the map to see your own data using either your Boatname if you entered one into the app or, your User ID.


Thanks for asking. I realise that was anything but, 'short' :)



Secchi(1).JPG
 
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