An ocean is a massive body of saline water that is present in the highest quantity on Earth.
- Oceans cover around 71% of Earth’s surface.
- It contains 97% of Earth’s water ( salty water ).
# NOTE : –
In actual there is only one single connected ocean.
TYPES OF OCEANS
The different types of oceans are :
- Pacific ocean ( the largest of all )
- Atlantic ocean
- Indian ocean
- Antarctic ocean or Southern ocean
- Arctic ocean
# SIZE OF OCEANS
Pacific > Atlantic >Indian >Antarctic > Arctic Ocean
WHAT IS OCEAN ACIDIFICATION ?
Ocean acidification is mainly due to our : –
- anthropogenic activities and
- Some natural activities.
The ocean absorbs more than 25% of the carbon we deposit in the atmosphere .
WHY OCEAN IS GETTING ACIDIC ?
The ocean is getting much more acidic than before due to : –
- Our increased emissions, so more CO2 enters into the oceans.
The rate of ocean acidification is about : –
100 times greater than that experienced by marine ecosystems millions of years ago.
Since the beginning of Industrialization : –
- Ocean has become 30% more acidic.
If we continue to burn more and more fossil fuels and place more carbon into the atmosphere then : –
- The ocean will become more acidic.
According to a recent report : –
If we continue to do so then by the end of 21st century , the ocean will be : –
150% more acidic which oceans have not experienced for more than 20 million years.
As the ocean acidifies, some organisms adapt but some do not.
# HARMFUL EFFECTS
Even a small change in acidity level of water can have harmful effects on marine life , affecting : –
- Reproduction and
# IMPACT OF OCEAN ACIDIFICATION
The impacts observed are : –
- Coral reefs which are vital for marine life are likely to get eroded very quickly.
- Ocean acidification will also threaten the planktons which is a key to the survival of larger fish.
- Fish species suffer a condition called acidosis ,affecting their survival.
- There will be difficulty for life to sustain.
# OTHER ANIMALS
Other shelled animals like : –
- Urchin will face trouble building their shells in more acidic waters.
WHAT ARE THE MAJOR THREATS TO THE OCEAN ?
The major threats to ocean are : –
- Illegal fishing
- Lack of protection
- Influence of Industries and Tourism
- Impact of shipping
- Effects of offshore oil drilling
- Dumping of waste
WHAT IS THE STATE OF GLOBAL OCEAN ?
The world ocean assessment examined the state of oceans and the ways in which human benefits from it.
It studied the following human pressures on the ocean : –
- Climate Change ( ocean acidification changing salinity and oxygen content )
- Human disturbance such as capturing fishes.
- Demand for ocean space
Inputs to the ocean such as : –
- Toxic substances
Underwater noise from : –
- Sonar and
- Seismic waves
# WORLD OCEAN ASSESSMENT CONCLUSION
- Human impacts on ocean are no longer minor.
- No part of ocean today is completely free from human interference.
- The impacts of human activities have pushed ocean’s carrying capacity almost to its limit.
- Climate change.
- Over-exploitation of marine living resources.
- It can lead to Overfishing.
# CONSERVE THE OCEAN
The ocean can be conserved by : –
- Take action to eliminate plastics from entering the ocean.
- Combat for illegal fishing .
- Monitor progress for a healthy ocean.
- Stop the disposal of solid waste.
- Increase protection level.
- Limit the growth of industries and emissions from them.
- Oceans should not be used as a battleground or testing fields.
- Ensure recycling of wastes.
- Not harming the animals for fun like collecting shells , making accessories.
” WATER WATER EVERYWHERE BUT NOT A DROP TO DRINK,