Section 3 Flashcards
What creates the natural greenhouse effect?
The water vapour in the atmosphere.
Which gases cause the enhanced greenhouse effect? How are they released into the atmosphere?
Carbon dioxide, methane, nitrous oxide.
They are released into the atmosphere through human activity.
What is GWP?
Global warming potential; it’s a measure of the relative ability to trap thermal energy in the atmosphere.
When measuring GWP, what gas is used as a reference for comparison to other GHGs?
carbon dioxide
What is the persistence of a gas?
How many years each gas will remain in the atmosphere.
How have ice core samples helped develop our knowledge about climate change?
The analysis of ice core samples (to give us an idea about the distant past) and atmospheric conditions have shown the levels of all three greenhouse gases in Earth’s atmosphere are increasing.
Since what time has the carbon dioxide level in the atmosphere been increasing?
Since the industrial revolution in the late 18th century.
What is a carbon source?
Any process that releases carbon into the atmosphere.
What are fossil fuels and what are they formed from? Why are they bad for the environment?
Fossil fuels are formed from the remains of living organic material, so they contain a lot of carbon. When burned, they release carbon dioxide and nitrous oxide into the atmosphere.
True or false: modern agriculture does not contribute to the level of greenhouse gases.
False
What are carbon sinks? Why has the amount of them been decreasing?
Things that remove carbon dioxide from the atmosphere; forests (photosynthesis removes carbon dioxide from the atmosphere). The human need for fuel and land for agriculture and industrialization has decreased the amount of carbon sinks.
How has the level of atmospheric carbon dioxide increased by 32% over the last 200 years?
The combination of increased use of fossil fuels and the decrease in available carbon sinks.
What are halocarbons? Where are they usually found?
They are another class of man made chemicals that can trap thermal energy in the atmosphere. they can be found in refrigerators and air conditioners.
Name four pieces of evidence for global warming (besides the increase of average global temperatures).
- flowers blooming earlier in the northern hemisphere
- more extreme weather events like ice storms and floods
- snow cover in polar regions decreasing
- increased avg. level and temp. of Earth’s oceans
What is the general circulation model (GCM)? What do they focus on?
- computer model of climate on a global scale
- GCM’s focus on the mechanisms of thermal energy transfer in the atmosphere, the complex factors that influence them, and how they are changing. These changes obviously have major implications for climate on different parts of Earth.