Climate Change: Understanding the Basics
Explore how climate change works, how it affects everyday life, and what climate projections can tell us.
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Questions with solutions-
1. Velg riktig svar.
What do these long-term patterns describe?
A coastal town has wet winters and dry summers when weather records are averaged over several decades.
- The town's climate
- The town's weather forecast for next week
- The town's most extreme recorded storm
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- The town's climate
Climate includes typical conditions, seasonal patterns, and variability over many years—not just average temperature.
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2. Fyll inn det tomme feltet.
How do greenhouse gases affect Earth's energy?
Greenhouse gases allow much of the Sun's light to pass through but absorb some of the ___ that Earth gives off.
- visible light
- infrared radiation
- ultraviolet radiation
Think about the energy released by a warm surface.
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Greenhouse gases allow much of the Sun's light to pass through but absorb some of the infrared radiation that Earth gives off.
This natural greenhouse effect keeps Earth warmer than it would be without these gases. Adding more greenhouse gases increases warming.
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3. Velg riktig svar.
Why does burning these fuels increase atmospheric carbon dioxide?
Coal, oil, and natural gas contain carbon that was stored underground for millions of years.
- It removes carbon dioxide by using up atmospheric oxygen.
- It transfers atmospheric carbon into long-term underground stores.
- It moves carbon from underground stores into the air.
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- It moves carbon from underground stores into the air.
During burning, carbon in the fuel combines with oxygen to form carbon dioxide.
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4. Fyll inn det tomme feltet.
Even without adding water from melting land ice, warmer oceans can raise sea levels because seawater ___ as it warms.
- expands
- contracts
- becomes denser
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Even without adding water from melting land ice, warmer oceans can raise sea levels because seawater expands as it warms.
Warmer seawater takes up more space. This thermal expansion and melting land ice both contribute to sea-level rise.
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5. Velg riktig svar.
Which action is an example of climate change adaptation?
A coastal town raises flood walls, adds solar panels, and insulates homes to reduce heating fuel use.
- Adding solar panels
- Raising flood walls
- Reducing heating fuel use
Which action helps the town deal with climate impacts rather than reduce their causes?
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- Raising flood walls
Adaptation reduces harm from climate impacts. Mitigation addresses the causes, mainly by reducing greenhouse gas emissions.
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6. Velg riktig svar.
What happens as more carbon dioxide dissolves in seawater?
The ocean absorbs some of the carbon dioxide released into the atmosphere.
- The water becomes less acidic.
- The water's acidity stays unchanged.
- The water becomes more acidic.
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- The water becomes more acidic.
Dissolved carbon dioxide forms a weak acid. This change can make it harder for some marine animals to build shells.
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7. Velg riktig svar.
How can this affect rainfall during storms?
Warmer air can contain more water vapor before becoming saturated.
- It can make heavy rainfall more intense.
- It guarantees more rainy days in every region.
- It makes heavy rainfall less intense by keeping water in the air.
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- It can make heavy rainfall more intense.
More available moisture can increase rainfall intensity. However, local rainfall also depends on winds and weather patterns, so some regions can become drier.
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8. Fyll inn det tomme feltet.
When bright sea ice melts, it exposes darker ocean water. The darker surface absorbs more sunlight, which can cause ___ warming.
- less
- no further
- additional
Bright ice reflects more sunlight than dark ocean water.
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When bright sea ice melts, it exposes darker ocean water. The darker surface absorbs more sunlight, which can cause additional warming.
This is a reinforcing feedback: an initial change triggers effects that strengthen that change.
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9. Velg riktig svar.
What gives the most complete comparison of their greenhouse gas emissions?
Two buses travel the same route for the same number of years. One runs on diesel; the other runs on electricity.
- Only emissions released from their exhaust pipes during use
- Emissions from manufacturing, energy supply, use, and disposal
- Emissions from manufacturing and disposal, excluding energy use
Consider what happens before, during, and after the buses are used.
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- Emissions from manufacturing, energy supply, use, and disposal
A life-cycle comparison includes more than exhaust emissions. For an electric bus, the way its electricity is generated also matters.
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10. Velg riktig svar.
What has the company achieved for its current carbon dioxide balance?
A company cuts most of its carbon dioxide emissions, then removes an amount equal to what it still releases.
- No carbon dioxide released at all
- More carbon dioxide removed than released
- Net-zero carbon dioxide emissions
Separate the amount released from the final balance after removals.
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- Net-zero carbon dioxide emissions
Net zero means releases and removals balance. It does not mean emissions have stopped or past emissions have been erased.
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11. Velg riktig svar.
Which conclusion is supported by this comparison?
Climate simulations using only natural influences do not reproduce the global warming observed in recent decades. Those that also include human influences match the trend much better.
- Human influences help explain recent global warming.
- Natural influences alone explain the recent warming trend.
- Human influences affect short-term weather but not long-term climate.
Notice which simulations better match the changes that have actually been measured.
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- Human influences help explain recent global warming.
Human greenhouse gas emissions are the main driver of recent global warming. Natural influences still affect the climate.
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12. Velg riktig svar.
Why can both projections be scientifically useful?
Two climate projections use the same model but different future emission pathways. They show different amounts of warming by the end of the century.
- They record two warming trends that have already occurred.
- They explore outcomes under different assumptions about future emissions.
- They show that future warming is independent of emissions.
A projection describes what could happen under particular conditions.
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- They explore outcomes under different assumptions about future emissions.
A projection depends on its assumptions; it is not an observation of the future. Different pathways help show how future emissions can affect climate risks.