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Laboratory  Introduc.on   What is a protocol?

What are greenhouse gases?

Why do scientists use protocols?

How do they contribute to climate?

Now let’s talk about ocean acidification!

Ocean  Acidifica.on   - What do you know? -  What have you heard? -  Ischia Island

Ischia  Island  

Ischia  Island   - What did you see? -  What more do you want to know?

Image from www.saveourseas.com

Let’s  do  an  experiment!   - What should we measure? -  How will we measure it?

Ocean  Acidifica.on  –  the  basics   1) Why carbon dioxide (CO2) is important •  •  • 

CO2 has increased in the atmosphere. The oceans have absorbed more CO2. The amount of CO2 in the oceans has greatly increased.

Carbon  dioxide  (CO2)  in  the  atmosphere  is  increasing   CO2 is increasing everywhere!!

Point Barrow, Alaska La Jolla, California Mauna Loa, Hawaii Christmas Island Samoa

South Pole, Antarctica

Why  does  the  increase  in  CO2  maCer?   —  If  water  vapor  (H2O)  is  

the  most  common   greenhouse  gas,  why   does  CO2  matter?  

—  CO2  is  a  powerful  

greenhouse  gas  

 

CO2

H2O Red = oxygen Black = carbon White = hydrogen

Solar Radiation passes through the atmosphere

Earth warms and emits infrared radiation

Infrared radiation is absorbed by greenhouse gases and re-radiated in all directions

What  is  radia.on?  

Light!

Image from www.antonine-education.co.uk

What  is  radia.on?  

Image from www.radios.2y.net

Light  is  converted  into  heat.   Infrared thermal images

Two people with a cold drink

Two sea lions sunning their chests

Photos by Heather Liwanag

Light  is  converted  into  heat.  

Pyrometer = ear thermometer Image from InternetShopUK.com

CO2   H2O  

Chihuahua Photo by Schenko

Old English Sheepdog Photo by pleple2000

Pre-industrial

Now

Why  does  the  increase  in  CO2  maCer?   —  If  water  vapor  (H2O)  is  

the  most  common   greenhouse  gas,  why   does  CO2  matter?  

—  CO2  is  a  powerful  

greenhouse  gas  

 

CO2  re-­‐emits  more,   keeping  more  heat   in  the  atmosphere  

CO2

H2O Red = oxygen Black = carbon White = hydrogen

Solar Radiation passes through the atmosphere

Earth warms and emits infrared radiation

Infrared radiation is absorbed by greenhouse gases and re-radiated in all directions

Earth’s atmosphere and Earth’s ocean “communicate” by exchanging gases O2

CO2

How  do  we  determine     how  CO2  affects  the  oceans?   —  What  can  we  measure?   —  What  materials  would  we  need?  

 

Bubbles!  –  Step  1   Get  control  and  experimental  water.     Control:  Room  temperature                      seawater   Experimental:   1.  Room  temperature     tap  water   2.  Cold  seawater   3.  Warm  seawater  

Bubbles!  –  Step  2   Add  indicator  to  the  control  water.    

Bubbles!  –  Step  3   Blow  bubbles  for  2  minutes  and  note  pH  changes.    

Bubbles!  –  Step  4   Repeat  for  one  experimental  condi.on.    

Room temp tap water

Cold seawater

Hot seawater

Bubbles!  –  Step  5   Graph  pH  changes  and  compare  results.    

pH

Time

Ocean  Acidifica.on  –  the  basics   1) Why carbon dioxide (CO2) is important •  •  • 

CO2 has increased in the atmosphere. The oceans have absorbed more CO2. The amount of CO2 in the oceans has greatly increased.

2)  The ocean’s chemistry has changed •  • 

A decrease in pH = acidification A decrease in CO32- ions — shell-building material

What do we know about acids and bases? 0

Battery Acid

1

Gastric Acid, Sulfuric Acid

100,000

2

Lemon Juice, Vinegar

10,000

3

Orange Juice, sodas

1,000

4

100

5

Tomato Juice Acid Rain Black Coffee, Bananas

10

6

Urine, Milk

0

7

Distilled Water

1/10

8

Human Blood Sea Water, eggs

1/100

9

1/1000

Baking Soda Toothpaste

10

Milk of Magnesia

11

Ammonia Solution

12

Soapy Water

13

Bleach

14

Liquid Drain Cleaner

10,000,000

Acids

Bases

Concentration of H+ ions compared to distilled water

1,000,000

1/10,000 1/100,000 1/1,000,000 1/10,000,000

Human Skin

Increased CO2 in the oceans changes the chemistry of the water When CO2 dissolves in seawater, carbonic acid is produced via the reaction:

CO2 + H2O ó H2CO3 Carbon dioxide

Water

Carbonic acid

The carbonic acid dissociates in the water, releasing hydrogen ions and bicarbonate:

H2CO3 ó H+ + HCO3Carbonic acid

Hydrogen ion

Bicarbonate

Acidity

doobybrain.com

The ocean needs to balance its chemistry CO2 + H2O ó H2CO3 ó H+ + HCO3Carbon dioxide

Water

Carbonic acid

Hydrogen ion

To decrease H+ and balance pH…

H+ + CO32- ó HCO3-

Hydrogen ion

Carbonate ion

Bicarbonate

Bicarbonate

Ocean  Acidifica.on  –  the  basics   1) Why carbon dioxide (CO2) is important •  •  • 

CO2 has increased in the atmosphere. The oceans have absorbed more CO2. The amount of CO2 in the oceans has greatly increased.

2)  The ocean’s chemistry has changed •  • 

A decrease in pH = acidification A decrease in CO32- ions — shell-building material

3)  Changes in chemistry affect biology! • 

Shelled organisms are affected (snails, clams, mussels, crabs…)

The ocean needs to balance its chemistry CO2 + H2O ó H2CO3 ó H+ + HCO3Carbon dioxide

Water

Carbonic acid

Hydrogen ion

To decrease H+ and balance pH…

H+ + CO32- ó HCO3-

Hydrogen ion

Carbonate ion

Bicarbonate

Where does the carbonate come from? Calcified shells are made of CaCO3 Ca2+

CO32-

Bicarbonate

The ocean needs to balance its chemistry

CO32CO32CO32-

CaCO3

Carbonate   Carbonate   Carbonate  

Bicarbonate   Bicarbonate   Bicarbonate  

2-­‐   CO32-­‐ CO3   CO32-­‐2-­‐     CO 3

HCO HCO3-­‐3-­‐  -­‐   HCO3   HCO HCO33-­‐-­‐     -­‐   HCO 3 HCO H CO33-­‐-­‐    

2-­‐ 2-­‐   CO C O 3   CO332-­‐

Carbonic acid H2CO3

Bicarbonate HCO3-

H+

Changes in chemistry affect biology! Decreasing pH = less material to build shells

Ca 2+ + CO3 2- à Calcium

Carbonate

CaCO3 Calcium carbonate Calcite and aragonite

How  do  we  determine  how  ocean   acidifica.on  affects  shelled  organisms?   —  What  can  we  measure?   —  What  materials  would  we  need?  

 

Shells!  –  Step  1   Label  and  weigh  your  mussel  shells.    

Shells!  –  Step  2   Put  untreated  shells  in  vinegar  and  seawater.    

Shells!  –  Step  3   Observe  the  experiment.            Observe  pre-­‐treated  shells.    

Shells!  –  Step  4   Remove,  dry,  and  weigh  experimental  and  control  shells.    

Shells!  –  Step  5   Test  strength  of  all  shells.    

Shells!  –  Lab  protocol   1.  Label  and  weigh  shells   2.  Place  untreated  shells    

in  vinegar  and  seawater   3.  Observe  experiment     and  pre-­‐treated  shells   4.  Remove,  dry,  and  weigh     expt’l  and  control  shells   5.  Test  strength  of  all  shells  

Laboratory  Follow-­‐up   Obstacles during the lab Give details! What was hard and why?

Solutions How can we make this lab easier to understand?

Now what?

Ocean  Acidifica.on  –  the  basics   1) Why carbon dioxide (CO2) is important •  •  • 

CO2 has increased in the atmosphere. The oceans have absorbed more CO2. The amount of CO2 in the oceans has greatly increased.

2)  The ocean’s chemistry has changed •  • 

A decrease in pH = acidification A decrease in CO32- ions — shell-building material

3)  Changes in chemistry affect biology! • 

Shelled organisms are affected (snails, clams, mussels, crabs…)

4)  We can already see effects, and yet we don’t know all of the outcomes •  • 

Laboratory studies Field studies

Field studies show ecosystem changes

VENT

You can already see effects and we don’t know all of the outcomes

Chi.n  

If ocean chemistry is changing world-wide, why should WE care??? If we change these… If we change these… these we change these Coccolithophorid (phytoplankton)

We eat these

and these…

and these… Pteropod (zooplankton)