Course review
Review each learning objective in this topic, then open its concept explanation or question set.
Learning objective
• Human activities increase atmospheric CO₂, methane, and other greenhouse gases • Fossil fuels, cement, agriculture, deforestation, and land-use change are major sources
Start with the concept explanation, then practise to create mastery evidence.
Learning objective
• Positive feedback amplifies warming after an initial climate change • Examples include ice-albedo loss, permafrost methane, ocean CO₂ release, and wildfire feedback
Start with the concept explanation, then practise to create mastery evidence.
Learning objective
• Boreal forests can shift from carbon sinks to carbon sources • Warming, drought, reduced snowfall, browning, insects, and fire increase tipping-point risk
Start with the concept explanation, then practise to create mastery evidence.
Learning objective
• Melting landfast ice and sea ice alters breeding, feeding, and resting habitat • Emperor penguins and walruses illustrate species dependent on ice timing and extent
Start with the concept explanation, then practise to create mastery evidence.
Learning objective
• Ocean warming strengthens stratification and can reduce nutrient upwelling • Reduced upwelling lowers phytoplankton productivity and food supply
Start with the concept explanation, then practise to create mastery evidence.
Learning objective
• Species ranges can shift poleward, upslope, or contract as climate zones move • Montane birds and North American tree species show changing distribution limits
Start with the concept explanation, then practise to create mastery evidence.
Learning objective
• Warming causes coral bleaching by disrupting coral-zooxanthellae mutualism • Ocean acidification suppresses calcification, threatening reef biodiversity and collapse
Start with the concept explanation, then practise to create mastery evidence.
Learning objective
• Carbon sequestration captures and stores atmospheric carbon dioxide • Afforestation, agroforestry, forest regeneration, and peatland rewetting increase carbon stores
Start with the concept explanation, then practise to create mastery evidence.