The oceans are getting acidified! How? Why? What can we do?
For answers... Check the Presentation out
(Just a bit more informative than my previous one)
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BASIC CONCEPT
Ocean acidification is the continuous decrease in the pH of the Earth's
oceans, caused by the diffusion of carbon dioxide (CO2) from
the atmosphere.
About 30–40% of the carbon dioxide released by humans into the
atmosphere dissolves into oceans, rivers and lakes. To
achieve chemical equilibrium, some of it reacts with the water to
form carbonic acid.
Before a few decades, the ocean water was basic. With time acidity of
the ocean water is rising.
4. HOW ACIDIC ARE THE OCEANS
The oceans are not acidic but, in fact, slightly basic.
Acidity is measured using the pH scale, where 7.0 is said to
be neutral, with higher levels called "basic" and lower levels called
"acidic".
Historical global mean seawater values are approximately
8.16 on this scale, making them slightly basic.
For example, pure water has a pH of 7.0 (neutral), whereas
household bleach has a pH of 12 (highly basic) and battery acid has a pH
of zero (highly acidic).
However, even a small change in pH may lead to large
changes in ocean chemistry. Over the past 300 million years, global
mean ocean pH values have probably never been more than 0.6 units
lower than today (6). Ocean ecosystems have thus evolved over time in
a very stable pH environment, and it is unknown if they can adapt to such
large and rapid changes.
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5. THE OCEAN IS A CARBON SINK
•THE OCEAN ABSORBS CO2 FROM THE
ATMOSPHERE
•PHYSICAL AND BIOLOGICAL PROCESSES MOVE
SOME OF THE CARBON TO THE DEEP OCEAN
WHERE IT IS STORED
•THE CAPTURE AND
STORAGE OF CARBON
IS KNOWN AS
CARBON SEQUESTRATION
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Our ocean
captures and
stores carbon
6. HOW MUCH CO2 CAN THE OCEAN ABSORB?
• THE TOTAL AMOUNT OF ANY GAS SEAWATER CAN ABSORB
DEPENDS ON TEMPERATURE AND SALINITY
• SALINITY IS A MEASURE
OF THE DISSOLVED SALT
CONTENT OF WATER
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Temperature
or
Salinity
Amount of gas
seawater can absorb
7. CARBON DIOXIDE IN THE OCEAN
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•Carbonate is used by marine organisms
like this pteropod (marine snail) to create
the compound calcium carbonate
•When dissolved in water, carbon dioxide
forms carbonic acid that primarily dissociates
into bicarbonate and hydrogen ions
•Some of the excess hydrogen ions combine
with carbonate, decreasing carbonate
availability to marine organisms.
8. IMPACTS ON OCEANIC CHEMISTRY
• Marine animals are unable to
survive.
• Destruction of food web
• Several ocean goods and
services are likely to be damaged
by future ocean acidification, (like
pearl industry)
• Calcification
• Vulnerable shelled animals
• Increasing the growth rate of the
sea star, Pisaster ochraceus
11. HUMAN CONTRIBUTIONS TOWARDS THIS
SUCCESSIVE ACIDIFICATION
TRANSPORTATION, INDUSTRY AND THINGS WE DO AT HOME,
LIKE USE ELECTRICITY, HAVE CONTRIBUTED TO RISING CO2
EMISSIONS TO THE ATMOSPHERE, WHICH ARE THEN
ABSORBED BY THE OCEAN
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13. PRESERVATION
• SOME PROGRAMS WORKING FOR OCEANIC ACIDIFICATION ARE:
1. OCEAN ACIDIFICATION PROGRAM (OAP) BY NATIONAL OCEANIC AND ATMOSPHERIC
ADMINISTRATION (NOAA)
2. UK OCEAN ACIDIFICATION (UKOA) PROGRAMS AND RESEARCHES
3. PRECISION MEASUREMENT AND EQUIPMENT LABORATORY (PMEL) WHICH IS ANOTHER SUB-
DIVISION OF NOAA.
• STEPS TAKEN BY THESE PROGRAMS:
1. CREATING PUBLIC AWARENESS
2. CONDUCTING RESEARCHES THAT HELP IN MAXIMUM EXPANSION OF KNOWLEDGE AND TAKING
APPROPRIATE ACTIONS FOR REDUCTION IN THIS OCEAN ACIDIFICATIONS.
3. DRAFTING PLANS FOR FUTURE REDUCTION OF THE SAME WITH SEVERAL OTHER CO-
OPERATIONS.
• TILL DATE NO STEPS HAVE BEEN TAKEN AS SUCH FOR THE REDUCTION OF THE ACIDIFICATION.
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Photo: NOAA
14. OUR CONTRIBUTION TOWARDS
REDUCTION
• WE CAN ADOPT THE FOLLOWING MEASURES FOR OUR CONTRIBUTION
TOWARDS THE REDUCTION OF OCEANIC ACIDIFICATION:
1. WE CAN REDUCE OUR CARBON FOOTPRINT BY: SWITCHING TO ENERGY
EFFICIENT PRODUCTS, DROPPING THE TEMPERATURE OF OUR WATER
HEATERS FROM 60O C TO 400 C AND BY SWITCHING OF APPLIANCES AT
THE PLUG POINT.
2. BY PLANTING TREES THROUGH PROCESSES LIKE REFORESTATION AND
AFORESTATION.
3. REDUCING OUR VEHICLE USE WHICH IS A MAJOR CAUSE FOR EMISSION
OF CARBON-DIOXIDE.
4. BY USING THE THREE R’S OF WASTE MANAGEMENT
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