INTRODUCTION ABOUT OCEAN CURRENTS TYPES OF OCEAN CIRCULATION FACTORS THAT CAUSE & AFFECT OCEAN CURRENTS EFFECT OF OCEAN CURRENT RELATION OF OCEAN CURRENT WTH MARINE LIFE AND CLIMATE CHANGE

1. By: Anamika Raj
BSc. Botany Hons Part - 2
Roll no. : 662
Exam Roll No.: 18SBOT037575

2. Content :
• Introduction about ocean currents
• Types of Ocean Circulation
• Factors that cause and affect ocean currents
• Effect of Ocean Currents
1. Ocean Current & Marine life
2. Ocean Current & Climate Change
• References

3. OCEAN
CURRENTS
Ocean currents, abiotic features of the environment, are
continuous and directed movements of ocean water.
INTRODUCTION:

4. * Types Of Ocean Circulation
• Wind-driven circulation forced
by wind stress on the sea surface
fueled by energy from sun.(
Surface Currents)
• Thermohaline circulation driven
by the variations in water density
imposed at the sea surface by
exchange of ocean heat and water
with the atmosphere.(Deep
Currents)
Fig : Ocean Circulation

5. * Factors that cause and
affect Ocean Currents
• Wind Energy
• Solar Energy
• Density differences in water masses
caused by temperature and salinity
differences
• Gravity
• Events like earthquake & storm
Fig: Surface & Deep
Currents

6. **Effect of Ocean Currents
• Transfer heat from tropical (warmer) to polar
(colder) regions.
• Influence local and global climate.
• Provide oxygen to deep sea.
• Biological influence
1. Influences food webs and reproduction of marine
organisms (MARINE ECOSYSTEM).
2. Many species with limited mobility are dependent on this
"liquid wind" to bring food and nutrients to them and
to distribute larvae and reproductive cells.

7. Continuation...
• These currents support the
growth of phytoplankton
and seaweed which provide
the energy base for higher
consumer in the food chain,
including fish, marine
mammals, and humans.
Fig : Marine ecosystem

8. Plankton connectivity and
island biogeography • Many plants and animals in the
ocean drift during one or more
stages in their life.
• Phytoplankton, zooplankton,
bacteria and viruses spend their
entire life drifting.
• Currents results in reduction of
oceanographic distances and
shape population genetic structure
& the evolution of species through
the impact of drifting life stages
on the rates of gene flow.
Fig Showing: Phytoplankton
Ocean Currents and Marine life

9. Ocean Currents mediate evolution in island lizard
Fig: After
Hurricane in the
Bahamas island
Brown anoles : Hit more
often by tropical storms
and had larger toepads Green anoles : Have smaller toepads
and may not hit by tropical storms
Fig : Before
Hurricane in the
Bahamas island

10. • Patterns of gene flow among Island
population of Anlois lizard are best
explained by prevailing ocean currents and
over- water dispersal has evolutionary
consequences.
• Across island, Divergence in fitness related
morphology decreases with increasing gene
flow.
Ocean Currents have influence on
the adaptive radiation of Anlois
lizard

11. Fig : Tortoise are carried by
ocean currents to colonize new
areas
Fig :Eggs, larvae, and young drift
passively with the current,
although migration of adult fish
toward breeding grounds is
usually against the current.
Continuation..

12. Ocean Currents & Climate
Change
• Ocean currents acts a conveyor belt
• It transport warm water and precipitation
from the equator toward the poles and cold
water from the poles back to the tropics.
• Thus, ocean currents regulate global climate
• It helps to counteract the uneven distribution
of solar radiation reaching Earth’s surface.
• Without currents in the ocean, regional
temperatures would be more extreme—super
hot at the equator and frigid towards the
pole.
Fig: Ocean currents

13. References...
• https://oceanexplorer.noaa.gov/facts/climate.html#:~:text=O
cean%20currents%20act%20much%20like,solar%20radiati
on%20reaching%20Earth%27s%20surface.
• https://www.britannica.com/science/migration-animal/Fish
• https://www.sciencedirect.com/science/article/pii/S0960982
217300775
• Current biology magazine
• https://wildlife.org/hurricanes-can-shape-lizard-evolution/

14. THANK YOU