## Tuesday, 1 March 2016

### Comments from Sharky! (The Sand)

Hello!

So you have already gathered and analysed the data referring to the sand!
Let's have a look... (data updated 29th March 2016)

Ok, first of all I would like to remind you that it is very important to know where your data comes from, so you must write your coordinates as accurately as possible. This is the little problem that I see with the Liceo Scientifico Alberti, removing the decimals gives you the coordinates of a point inland between Maracalagonis and Burcei, not your beach. Also Ins Front Marítim should go over them, since they are a little inland too. You can check it up by entering your coordinates on Google Earth.

Now let's have a look at your data. This is very interesting, you have natural beaches and beaches that have undergone artificial nourishment. The difference is that the size of the grains of sand (granulometry) on natural beaches is going to be more even because they have been selected by the action of wind, rivers, waves and currents during their transportation. Artificially added sand has more of a mixture. So let's analyse the natural beaches of L'Estartit, La Fosca and Castell first.
Finish the sentence:
(1) The finer the sand is, the ......................... (narrower/wider) the heap of sand is and the beach face inclination tends to be .......................... (steeper/flatter).

Now let's have a look at the beaches of Poetto and Mar Bella. They both have the same inclination of the beach face, but the diametre of their heaps of sand is quite different.
(2) Looking at the diametre of the heaps of sand: which beach has finer grains?
Finish the sentence:
(3) Looking only at the diametre of the heap of sand Mar Bella is like .........................(L'Estartit/La Fosca/Castell) beach and Poetto like ......................... (L'Estartit/La Fosca/Castell).

(4) Would you give the same answers when looking at the inclination of the beach face? What do you think it has happened?

And you can send your data if you haven't done it yet! The Sand >>

Sharky

1. Hello,
I'm Clàudia from pla singular, institut montgri.
We made a mistake with our GPS coordinates, the real one are:
Latitude: 42º 2' 57,4" N
Longitude: 3º 11' 56,24" E
have a nice day!!!

1. Hello Clàudia, thank you for the information! I'll speak to the S'Agulla team to update your data. WELL DONE!

2. Good morning Clàudia. We have just updated your data. Thank you for the corrections!

2. Hello I am Kevin. I am finishing the sentence: The finer the sand is, the wider the heap of sand is and the beach face inclination tends to be flatter.
Bye!!

1. Hello Kevin, thank you for answering! Do the rest of participating schools agree with Kevin?

2. Hello Kevin! I see that the students of Ins. Front Marítim also agree with you. Yes that's the right answer. CONGRATULATIONS!

3. Hola sóc Isabel. Mirant el diàmetre del piló de sorra. jo crec que L'Estartit s'assembla a Poetto Beach.

1. Hello Isabel! I'm sure that what you say is very interesting, but do you mind repeating in English please? THANK YOU! ;D

2. Hello I am Isabel. Friom the diametre of the heap of sand, I think L'Estartit beach is very similar to Poetto.
Bye!!!

3. Hello Isabel! Yes, looking at the shape of the heap of sand it is very similar. But the inclination of the slope of the beach is not quite the same. Why?
Look at the comments from Ins Front Marítim and you'll get some clues...WELL DONE!

4. We are 1stC class from INS Front Marítim. We have send our data about water and sand yesterday. Sorry for the delay.

1. Hello!!! Happy to hear from you again, I was beginning to wonder if you had been eaten by a giant squid!
Excellent data, especially the conclusions of the water!
About the sand I'm afraid you'll have to go over the coordinates again.
THANK YOU!

5. Hello, I am Ferran from the 1st B and I'm going to answer your questions:
(1) The finer the sand is, the wider the heap of sand is and the beach face inclination tends to be flatter.

1. Hello Ferran! Thank you for answering this question. I see you agree with the students of Ins. Montgrí. Yes, that's the right answer. CONGRATULATIONS!

6. Now let's have a look at the beaches of Poetto and Mar Bella. They both have the same inclination of the beach face, but the diametre of their heaps of sand is quite different.
(2) Looking at the diametre of the heaps of sand: which beach has finer grains?
Finish the sentence:Poetto has finer sand than Nova Mar Bella but we think that Poetto's inclination of the heap of sand it's wrong.

1. Hello! Yes, that could be a possibility but I don't think so. When sand is added artificially to a beach, there is a bigger mixture of grain sizes than what you find in nature because they have not been selected by the effect of wind, waves and currents. This bigger mixture makes that sand gets piled up more easily. So although in Poetto beach the average size of the grains of sand is smaller, the mixture of sizes makes it behave a little different from the natural beach of l'Estartit.
However, it also depends if lately there has been rough sea and strong winds that the inclination of the beach profile will vary.
WELL DONE!!!

7. Hello Ins Front Marítim 1D. Happy to see your data and very good conclusions! WELL DONE!