Climate Change Flashcards
All 22 cards in this deck
What do tree rings tell scientists about past climate?
Each year's ring thickness shows the growing conditions — thicker rings mean warmer, wetter years.
Which parts of the world are projected to experience the greatest temperature rise by 2100?
High latitudes — areas north of 60°N (the Arctic) — warm most; the tropics warm least.
True or false? Arctic sea ice extent in September has increased since 1980.
False. It has fallen — roughly 3 million km² smaller by 2016 than in 1980.
How do orbital changes act as a natural cause of climate change?
The Earth's orbit stretches, and its axis tilts and wobbles (Milankovitch cycles), changing how much solar energy reaches Earth over tens of thousands of years.
How does volcanic activity act as a natural cause of climate change?
Large eruptions throw ash and sulfur dioxide into the atmosphere, reflecting sunlight back to space and causing short-term cooling.
How does solar output act as a natural cause of climate change?
The Sun's energy output varies with sunspot activity in cycles of about 11 years, so slightly more or less heat reaches Earth.
How does the use of fossil fuels cause climate change?
Burning coal, oil and gas releases carbon dioxide, which traps outgoing heat and strengthens the greenhouse effect (the enhanced greenhouse effect).
How does agriculture contribute to climate change?
Livestock and flooded rice paddies release methane, and fertilisers release nitrous oxide — both powerful greenhouse gases.
How does deforestation contribute to climate change?
Fewer trees absorb less carbon dioxide, and burning or rotting timber releases the stored carbon back into the atmosphere.
True or false? Natural factors such as volcanic activity are the main cause of global warming since 1950.
False. Recent rapid warming is mainly caused by human greenhouse gas emissions; natural factors explain longer-term Quaternary changes.
Give three effects of climate change on people.
Water supplies become less reliable in drought-prone areas; crop yields fall, threatening food supply; heat stress and diseases such as malaria spread, and people migrate away from flooded or arid areas.
Give three effects of climate change on the environment.
Ice sheets and glaciers melt, sea levels rise and flood low-lying coasts, ecosystems and species' habitats shift or are lost, and extreme weather becomes more frequent.
How might climate change affect the distribution, frequency and intensity of tropical storms?
Warmer oceans spread the area above 27°C further from the Equator, so storms may form in new regions; overall numbers may not rise much, but a greater proportion will be high-intensity (category 4–5) storms.
How does alternative energy production help mitigate climate change?
Replacing fossil fuels with renewables such as wind, solar and hydro produces electricity with almost no carbon dioxide emissions.
What is carbon capture and storage (CCS) as a mitigation strategy?
Carbon dioxide from power stations and industry is trapped before it reaches the atmosphere and piped into stores such as old oil and gas fields deep underground.
How does planting trees help mitigate climate change?
Growing trees absorb carbon dioxide during photosynthesis, acting as a carbon sink (afforestation).
Name an international agreement on climate change and what it aims to do.
The Paris Agreement (2015) — countries set their own targets to cut emissions and keep global warming well below 2°C, aiming for 1.5°C.
How can changing agricultural systems help people adapt to climate change?
Growing drought-resistant or new crop varieties, changing planting dates, and using irrigation or shade so farming can continue in altered conditions.
How can water supply be managed as an adaptation to climate change?
Reduce demand with metering and efficient appliances, and increase supply with reservoirs, water transfer schemes, rainwater harvesting or desalination.
How can the risk from rising sea levels be reduced as an adaptation to climate change?
Build or raise sea walls and flood barriers, restore mangroves and salt marsh, and avoid building on, or relocate from, low-lying coasts.
True or false? Building higher sea walls to cope with rising sea levels is an example of mitigation.
False. It is adaptation — it responds to the effects rather than reducing the causes of climate change.
True or false? Mitigation needs international cooperation to work, while adaptation can be done locally.
True. Emissions affect the whole atmosphere, so cuts need global agreements, but adaptation schemes protect particular places.