Impacts of Climate Change
Glacial Retreat: Higher global temperatures lead to a negative mass balance in glaciers and ice caps, meaning they lose more ice through melting and calving than they gain through snowfall.
Thermal Expansion: As ocean temperatures rise, water molecules move more vigorously and take up more space, contributing significantly to global sea level rise alongside meltwater input.
Permafrost Degradation: The thawing of frozen ground in high latitudes destabilizes infrastructure and releases stored greenhouse gases like methane (), further accelerating the warming process.
Water Security: The depletion of aquifers and the loss of reliable glacial meltwater threaten the availability of clean water for drinking, sanitation, and industrial use.
Agricultural Vulnerability: Shifts in rainfall patterns and increased frequency of extreme heatwaves can lead to crop failure, reduced yields, and increased food prices globally.
Health Risks: Warming climates expand the range of disease vectors like mosquitoes and increase the incidence of water-borne diseases following extreme flooding events.
| Feature | Mitigation | Adaptation |
|---|---|---|
| Primary Goal | Reducing the causes of climate change (e.g., cutting emissions) | Adjusting to the effects of climate change (e.g., building sea walls) |
| Timeframe | Long-term global benefit | Immediate to medium-term local benefit |
| Example | Transitioning to renewable energy | Developing drought-resistant crop varieties |
Weather vs. Climate: Weather refers to short-term atmospheric conditions (hours to days), whereas climate is the long-term average of these conditions over decades.
Eustatic vs. Isostatic Change: Eustatic change refers to global sea level rise due to water volume changes, while isostatic change refers to local land level changes relative to the sea.
Link Physical to Human: When discussing an impact like 'melting glaciers', always follow through to the human consequence, such as 'loss of seasonal irrigation water for downstream communities'.
Identify Feedback Loops: Look for opportunities to explain how one impact (like permafrost melt) creates a cycle that worsens the original cause (methane release leading to more warming).
Use Specific Terminology: Distinguish between 'water stress' (difficulty finding water) and 'water scarcity' (physical lack of water) to demonstrate higher-level understanding.
Check for Multi-causality: Remember that human activities like over-abstraction of groundwater often exacerbate the impacts of climate-induced drought.
Ozone vs. Greenhouse Effect: A very common error is confusing the hole in the ozone layer (which allows UV radiation in) with the greenhouse effect (which traps infrared heat). They are distinct phenomena.
Local vs. Global: Do not assume that a cold winter in one specific location disproves global warming; climate change refers to the shift in global averages and increased variability.
Sea Ice vs. Land Ice: Remember that melting sea ice (like the Arctic) does not significantly raise sea levels because it is already displacing its own weight; melting land ice (Antarctica/Greenland) is the primary contributor.