2.4 Green house effects and ocean currents Flashcards
not die (16 cards)
What are greenhouse gases and examples.
Gases that trap heat close to Earths surface. Water vapor, CO2, methane, ozone.
What is the greenhouse effect
The warming of Earth caused by greenhouse gases
What is enhanced greenhouse effect (climate change, global warming)
The impact on the climate from the additional heat retained due to
the increased amount of greenhouse gases that humans have released
into the earths atmosphere since the industrial revolution
What type of radiation does the sun project
Short wave radiation
What is the effect of short wave radiation
Is absorbed by clouds and earths surface and radiated back out into space as long wave radiation (heat). Greenhouse gases alow SWR to pass through.
Effects of long wave radiation?
However some greenhouse gases (water vapor CO2) absorb the out-going long wave radiation (heat) and they re-emit the heat in all directions including the Earth’s surface thus trapping heat closer to the surface keeping Earth warm.
What are ocean currents
Are continuous movements of ocean water. The circulation plays an important role in determining the climate of many different regions. Currents can be at the surface or deep in the ocean.
Main causes of currents are:
Wind, variations in salinity, temperature, the rotation of earth on its own axis, the gravitational pull of the sun and moon.
Describe surface currents
Wind pushes surface water until it reaches land, and flows either left or right. Can form circular patterns or a large system of rotating ocean currents aka gyre.
Describe the different gyres in different hemispheres
Northern Hemisphere -> clockwise
Southern Hemisphere -> anti clockwise
Describe deep ocean currents (salinity and density of water)
Deep currents begin at poles very cold water. As sea ice forms, water gets saltier due to salt not freezing and gets left behind in the water. As this saltier denser water sinks, it is replaced by surrounding water = formation of deep current. While this cold water moves along bottom of ocean towards equator, becomes less dense and warmer rising to surface again.
What is Thermohaline circulation
When surface and deep water currents interact to form. It is the movement of ocean currents due to differences in temperature and salinity in different regions of water. Important as it evenly distributed heat around the world.
What is the gulf stream
Current that makes western Europe warmer in winter. Also part of Thermohaline circulation. Stream feeds into North Atlantic Drift and Norweigian Currents and into labarador and Greenland seas. Cold artic winds cool stream water increasing density and creates cold deep current that flows to antarctica
What is the use of phytoplankton
Used as the first link in all food chains of the ocean.
What is phytoplankton where do they live
A microscopic photosynthertic organism:bacteria. Lives near surface as rely on sunlight for photosynthesis=most marine life lives on surface
How does thermohaline circulation help
- Bring organic matter from deep ocean to surface
- To take oxygen rich water down to decomposer organisms that live in the depths of the ocean.
Without ocean currents, rising of nutrients and sinking of oxygen and waste will stop and collapse ecosystem.
