Ecology: Climate change
Assessing claims—assessment of the claims that human activities are producing climate change
Understandings:
• Carbon dioxide and water vapour are the most significant greenhouse gases.
• Other gases including methane and nitrogen oxides have less impact.
• Carbon dioxide and water vapour are the most significant greenhouse gases.
• Other gases including methane and nitrogen oxides have less impact.
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• The impact of a gas depends on its ability to absorb longwave radiation as well as on its concentration in the atmosphere.
• The warmed Earth emits longer wavelength radiation (heat).
• Longer wave radiation is absorbed by greenhouse gases that retain the heat in the atmosphere.
• The warmed Earth emits longer wavelength radiation (heat).
• Longer wave radiation is absorbed by greenhouse gases that retain the heat in the atmosphere.
Global temperatures and climate patterns are influenced by concentrations of greenhouse gases.
• There is a correlation between rising atmospheric concentrations of carbon dioxide since the start of the industrial revolution 200 years ago and average global temperatures. Application: Correlations between global temperatures and carbon dioxide concentrations on Earth. Is there evidence to show this correlation? Watch the video for an interesting experiment... |
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Recent increases in atmospheric carbon dioxide are largely due to increases in the combustion of fossilized organic matter.
Ozone depletion is not the cause of the enhanced greenhouse effect.
Ozone depletion is not the cause of the enhanced greenhouse effect.
Theory of knowledge:
The precautionary principle is meant to guide decision-making in conditions where a lack of certainty exists. Is certainty ever possible in the natural sciences? |
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Application: Evaluating claims that human activities are not causing climate change.
International-mindedness:
Release of greenhouse gases occurs locally but has a global impact, so international cooperation to reduce emissions is essential.
Release of greenhouse gases occurs locally but has a global impact, so international cooperation to reduce emissions is essential.
So what is the debate? What do you think?
Read below for more information what we know about climate change now. |
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Application: Threats to coral reefs from increasing concentrations of dissolved carbon dioxide.
Application: The symbiotic relationship between Zooxanthellae and reef-building coral reef species.
Application: The symbiotic relationship between Zooxanthellae and reef-building coral reef species.
HHMI biointeractive activity: Corals get their energy in part from microscopic symbiotic algae that live inside their cells. These algae, called zooxanthellae, produce sugar and other nutrients through photosynthesis. When ocean temperatures rise beyond a certain threshold, the symbiont’s photosynthetic machinery may be damaged and produce harmful reactive oxygen molecules, causing the corals to eject the algae. Without their golden-brown colored symbionts, corals becomes a ghostly white in a process called bleaching and eventually die.
Watch the following before completing the activity: Download the student activities from this site. The activity looks at analyzing and graphing real data on coral bleaching and rising ocean temperatures. You will need the
data from the link on the right. |
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