Unit 3 - Climate Change Flashcards
Albedo:
The proportion of radiation reflected by a surface
High albedo- ice, snow, clouds
Low albedo- water, vegetation, sand
Climate:
Set of environmental conditions averaged over many years
Weather:
Set of environmental conditions encountered from day to day
Convection:
Cold air sinks, warm air rises, causing convection. Therefore the transfer of energy by the movement of particles of a fluid (gas or liquid) due to density differences. Since warmer fluids are less dense than cold ones, they rise above the cold fluids. This movement causes convection currents.
Name all of the Earth’s tropics from North to South:
Arctic circle, Tropic of Cancer, equator, Tropic of Capricorn, Antarctic circle
Explain the relationship between the tilt of Earth’s axis, seasons and distribution and concentration of sunlight on its surface:
The reason for seasons is all because of the Earth’s tilt. The earth travels in a loop around the sun each year. Summer happens in the hemisphere tilted towards the sun, therefore the light rays are hitting that location directly. Winter happens in the hemisphere tilted away from the sun, as the light rays have longer to travel and more time to scatter.
Describe the distribution of the suns energy that is absorbed and reflected and factors that affect it:
Energy affecting climate comes from the sun. 30% is reflected and 70% is absorbed. When energy is absorbed it is converted from visible light to heat. Little amounts radiate back into space, but most is trapped by the atmosphere by greenhouse gases including CO2, methane, water, ozone and nitrous oxide. Therefore the factors that affect absorption of energy are the greenhouse gases.
Greenhouse effect:
The greenhouse effect is a natural phenomenon has been around for millions of years. It keeps the earth from experiencing extreme temperature fluctuations and keeps average temperature higher than it would be without the effect. Greenhouse gases include: CO2, methane, water, ozone and nitrous oxide.
Describe the global convection currents and explain how they give rise to global winds:
Cold air sinks and warm air rises, causing convection. Air always flows from an area of high pressure to an area of low pressure which is experienced on the surface as wind.
What causes high pressure, and what weather is associated with it?
High pressure is caused from air sinking, and there will be fair weather.
What causes low pressure, and what weather is associated with it?
Low pressure is caused from air rising. As water vapour rises in the atmosphere this causes cloud formation and precipitation
Phyosynthesis:
The process by which green plants and some other organisms use sunlight to convert food into carbon dioxide and water. (Sink) Energy + Carbon dioxide (CO2) + water > sugars + oxygen
Respiration:
Burning of fuels, (source) done by decomposers
Source:
Processes that add CO2 to the atmosphere eg. Respiration, combustion, decomposition, volcanic eruptions
Sink:
Processes that remove CO2 out of the atmosphere or out of circulation eg. Photosynthesis, solution, mineralization
Combustion:
Burning of fuels (source)
Solution:
(Sink) a mixture of two or more substances
Dissolution:
When one substance dissolves in another substance.
Eccentricity: (Milankovitch cycle)
The shape of earths orbit around the sun. Th duration of this process lasts 100,000 years long.
Tilt: (Milankovitch cycle)
The earth tilts back-and-forth on its axis, the angle increases as seasons change. The duration of this process is 41,000 years long.
Precession of tilt (wobble): (Milankovitch cycle)
The earth spins on its axis, it slowly wobbles and the angle stays about the same. This process lasts 26,000 years.
Continental drift:
The theory explaining the slow movement of the large plates of earths crust. It affects the climate because it changes the distribution of land around the globe. It exists in all time frames.
Volcanic eruptions:
The sudden occurrence of a violent discharge of steam and volcanic material. The timeframe of this process is very short.
When all three Milankovitch cycles are combined, how many years are used up with in the cycles altogether?
Together these three cycles combine to cause 100,000 year cycles in Earth’s climate.