Flashcards in Climate Change Deck (46)
What is the definition of Weather?
The environmental conditions such as wind, pressure, temp, amount of precipitation, etc. in a specific place at a specific time.
The characteristic pattern of weather conditions within a region, including average monthly temps, precipitation, wind velocity and other conditions averaged over a long period of time. (Years)
Definition: Solar Activity
The amount of radiation the earth recieves from the sun is not constant. These variations in solar radiation may have an affect on the earths climate.
What does the sun have to do with our weather?
It is the driving force of our weather systems. It provides the energy that produces wind, rain and other factors of climate.
The flucuation of the Earths orbit around the sun due to the gravitational attraction to other planets. Over a cycle of 100 000 years the earths orbit changes from being almost circular to more eliptical.
The tilt of the Earth on its axis changes by approximately 2.4 degrees over a period of 41000 years. The greater the tilt, the greater the temp difference between summer and winter.
Because the earth is not a perfect sphere it wobbles on its axis.
SInce the earths surface is curved a beam of light illuminates different sized areas at different latitudes. The equator absorbs more energy and the poles absorb less.
The fraction of incident light or electromagnetic radiation that is reflected by the surfaces of an object, such as from back into space. It is the objects ability to reflect light.
Is the earths solid crust. it is composed of massive sections of solid rock. These sections are known as tectonic plates. Every year these plates move a few centimetres. This causes changes to both land and water masses which in turn, affects air and water circulation. Changes in air and water circulation affect water patterns.
Defenition: Volcanic Eruptions
Tectonic plate movement is responsible for volcanic activity. When volcanoes erupt, they spew ash and particulate matter into the atmosphere. These particles called aerosols reflect solar radiation and thus have a cooling effect on the global climate.
A thin layer of gases that surround a planet or moon.
What does the earths atmosphere consist of?
Consists primarily of nitrogen approx 78% and oxygen approx 21%.
What are gases that absorb and re-emit infrared radiation?
What are some gases that dont absorb and re-emit heat?
Nitrogen and oxygen. They do not to the natural greenhouse effect that keeps out planet warm enough for life.
Layers of the atmosphere
The atmosphere has been divided into 5 sections: The troposphere, stratosphere, mesosphere, thermosphere, and exosphere. Weather occurs mainly in the troposphere and lower stratosphere.
The Greenhouse Effect
The proccess by which gases build up thermal energy in the atmosphere by absorbing infrared radiation from the earths surface
What are some natural greenhouse gases?
Water vapour, CO2, methane, nitrous oxide, and ozone. There are 2 sources of ozone. - Ground level that contributes to greenhouse gases, and stratospheric ozone that protects us from UV rays.
What are some man made Greenhouse gases?
Chlorofluorocarbons (CFC's), and excess co2 from the burning of fossil fuels.
What is the anthropogenic greenhouse effect?
The increase in global average temperature, as a result of an increase in greenhouse gases due to human activities.
The movement of air from an area of high pressure to an area of low pressure.
What does wind effect?
Wind effects the movement of ocean currents, and precipitation patterns.
Defenition: prevailing winds
Winds that blow in fairly constant directions that cover large areas around the world.
Definition: Jet streams
High altitude winds that travel long distances at very high speeds. Jet streams may carry warm, moist or dry air or cool.
Definition: Heat resevoirs
Water stores more heat than air. Water has a large specific heat capacity. Therefore water heats up slowly and releases heat slowly. water acts as a buffer to temp. changes in the atmosphere. Land masses near large bodies of water are warmer in the winter than more inland areas.
How does solar energy travel?
It travels through space as electromagnetic radiation.
What type of radiation keeps our planet and the things on it warm?
transfer of energy, including thermal energy, as electromagnetic radiation. This energy can travel through a vacuum. It can be absorbed, reflected or refracted.
The transfer of thermal energy between 2 objects that are in direct physical contact. Thermal energy always moves from a region of high temperature to an area of lower temperature.