ESS Flashcards
Earth Systems
The Earth is made up of 4 distinct yet connected systems: atmosphere, biosphere, lithosphere, and the hydrosphere.
Atmosphere
The layer of gases surrounding the Earth
Biosphere
The part of the Earth composed of all the living organisms on the planet including plants, animals, bacteria, etc.
Lithosphere (geosphere)
The part of the Earth composed of all the rocks, minerals, molten magma found on the surface and underground. Includes only non-living stuff
Interaction
These spheres interact together to influence factors such as landscape, soil formation, change in temperature, biodiversity, and salinity. For example, the interaction of spheres influence temperature differences. The mountain ranges of the lithosphere interact with the low air pressure of the atmosphere and the snowy precipitation of the hydrosphere to produce an icy climate. This climate drives adaptations vital for organisms of the biosphere.
Hydrosphere
The part of the Earth composed of all the water (solid, liquid, and gas) on Earth.
Liquid water (oceans, rivers, lakes, underground, etc), solid water (ice caps, glaciers, etc), and water vapour (clouds, rain, snow, etc)
Cryosphere – frozen water part of Hydrosphere
The carbon cycle
The path through which carbon is exchange between the 4 Earth Spheres by the processes of respiration, combustion, photosynthesis, decomposition, and fossilisation.
Respiration
The process of producing energy from sugar and oxygen and releasing CO2 and water in the process.
Combustion
Combustion is a high temperature chemical reaction between a fuel and an oxidant, producing Carbon dioxide and water in the process.
Photosynthesis
The process where green plants and certain other photosynthetic organisms transform carbon dioxide, water, and sunlight into oxygen and glucose.
Decomposition
Decomposition is the process by which dead organic substances are broken down into simpler organic or inorganic matter such as carbon dioxide, water, simple sugars and mineral salts.
Fossilisation
Fossilisation is the process of an animal or plant dying off and lithifying to form rock, storing carbon for long periods of time. Carbon is released back into the atmosphere when the fuel is burned.
How is Carbon cycled in the 4 Earth Spheres?
Carbon dioxide in the atmosphere is converted into glucose and oxygen during photosynthesis by plants, moving from the atmosphere to the biosphere. These plants respire which releases Carbon dioxide back into the atmosphere and also pass on Carbon to animals as they feed on it. When a plant or animal dies, they decompose which releases Carbon dioxide back into the atmosphere or fossilise to form rocks which is a part of the lithosphere, storing carbon for long periods of time before being burned and releasing Carbon dioxide back into the atmosphere. Marine plants and animals of the hydrosphere also conduct these processes.
Weather
Weather is the short-term change in atmosphere with respect to its effects on life form and human activities. It is thought of in terms of wind, temperature, precipitation, storm, humidity, etc.
Climate
Climate describes the predominant long-term pattern in weather in a particular region.
The natural greenhouse effect
The natural process that maintains Earth’s ideal surface temperature for plants and animals. When solar radiation from the sun reaches the Earth’s atmosphere, which includes heat in the form of infrared waves, some of it is reflected back to space, some of it is absorbed by the land and oceans, and some are trapped by greenhouse gases.
Greenhouse gases (GHGs) include: carbon dioxide, water vapour, methane, ozone, and nitrous oxide.
The greenhouse effect in cars
Solar radiation which includes visible light passes through a car glass/window due to its short wavelengths. Some of it is reflected back out but some are absorbed and re-radiated in longer wavelengths in the form of infrared waves which is heat. Infrared waves are unable to escape through glass and hence is trapped.
Thermohaline circulation
Deep-ocean currents driven by differences in water density due to differences in temperature and salinity.
Ocean water in polar regions gets very cold and forms sea ice which leaves salt behind. The surrounding cold and salty ocean water sinks as density increases until it can rise to the surface near the equator. Warm and less salty surface water from the equator is pulled in to replace the sinking water, which in turn eventually becomes cold and salty enough to sink. This creates the deep-ocean current and global conveyer belt that help redistribute heat around the globe.
Gyres
A large system of swirling surface currents, driven by the Coriolis effect in wind, tides, and differences in temperature and salinity. These currents help redistribute heat and warmth around the globe.
carbon sink
A carbon sink is any feature of the environment that absorbs and/or stores carbon, keeping it from the atmosphere.
4 main carbon sinks:
Soil: contains organic matter and decomposed organic matter of fossil fuels
Forest/plants: take in large amounts of Carbon dioxide via photosynthesis
Rocks: contains limestone, chalk, and carbonates
Oceans: contains dissolved CO2 and carbonates in shells of marine organisms
Global climate is influenced by a number of factors, including:
Latitude and the Earth’s tilt, Surface covering (water, land, ice, vegetation), Topography (mountains, plains)
Climate change
Climate change refers to major changes in the predominant long-term patterns of weather caused by natural variability and human activity.
Evidence of climate change in geological past
Fossilized plants and animals that normally live in certain environments have been found at much higher or lower latitudes than they could survive at today. This serves as evidence that climate change occurred in different parts of the globe.
Ice-ages: a period in Earth’s history when the ice on the polar caps significantly expands due to a lowering of the Earth’s global temperatures.
Inter-glacial periods: a period of warmer temperatures between ice ages where glaciers retreat and sea levels rise.
Natural causes include changes in the Earth’s orbit, the intensity of the sun, the circulation of the ocean and the atmosphere, and volcanic activity.
Latitude and the Earth’s tilt
At the equator, the sun’s rays are perpendicular to the Earth’s surface, exposing it to more heat.
At the poles, the sun’s rays are spread across a wider area, heating it up less than at the equator.
Global winds are caused by differences in atmospheric pressure due to the uneven heating of the Earth by the sun. Wind carries heat, moisture, pollutants and pollen to new areas.
Earth’s tilt causes six-month winter difference in northern and southern hemisphere.