Clean Energy

Frequently Asked Questions

• What is the greenhouse effect?
• What is climate change?
• Why are the concentrations in greenhouse gases changing?
• What are probable impacts of climate change?
• What can we do about it?

What is the greenhouse effect?

Some gases such as water vapor, carbon dioxide, methane, and nitrous oxide, play an important role in the energy balance of the Earth. They act like the glass roofs and walls in a greenhouse and trap heat within the Earth’s atmosphere. Without these gases, the surface temperature of the Earth would be about 35 degrees Celsius lower. This process is called the greenhouse effect and the gases involved are called greenhouse gases.

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What is climate change?

Climate change refers to the variation in the Earth's global climate or regional climates over time. It describes changes in the variability or average state of the atmosphere - or average weather - over time scales ranging from decades to millions of years. These changes may come from internal processes, be driven by external forces or, most recently, be caused by human activities.

Recent climate changes have been attributed to global warming, which is caused by the increase in atmospheric concentration of greenhouse gases, trapping more heat near the Earth’s surface. Global warming affects regional climate events such as rainfall patterns, evaporation, and cloud formation change.

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Why are the concentrations in greenhouse gases changing?

The natural concentrations of greenhouse gases, such as carbon dioxide (CO₂), methane (CH₄) and nitrous oxide (N₂O), are regulated by the Earth and its biosphere through uptake and release by natural cycles and through destruction in the atmosphere.

However, since the industrial revolution, the emissions of these gases have been significantly increased over a relatively short time mainly due to burning of fossil fuel, industrial processes, and increase in agriculture activities. Moreover, other 'non-natural' greenhouse gases were introduced such as the chlorofluorocarbons (CFCs), which are quite persistent in the atmosphere. At the same time, the ability of the Earth to absorb the major greenhouse gas - CO₂ is being reduced by unsustainable use of land and forests.

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What are probable impacts of climate change?

Based on computer models, scientists came to the conclusion that global warming will result in an increase in average global surface temperature, average global sea level rise, and a global increase in precipitation.

These changes will have an impact, among others, on

• Coastal areas (inundation of coastal lands including low-lying atolls, erosion of beaches and coastlines)
• Forests (geographical range, decrease of forest health and production)
• Agriculture (change in crops, change in yield, increased irrigation demands)
• Health (increase in diseases, weather related mortality)
• Water resources (change in supply, reduction of quality)

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What can we do about it?

Reduce the emissions of greenhouse gases by using energy more efficiently, switching to cleaner technologies, and looking for new resources.

• Using energy more efficiently, not only in electricity generation, but also in industrial processes and in transport can reduce CO₂ emissions
• Use of clean technologies, such as wind, solar, as well as proper use of biomass and biogas as fuel will result in reduction of greenhouse gases concentration in the atmosphere
• New fuel resources, such as hydrogen, might result in almost zero-emission energy generation

Not only in the energy sector can reductions be achieved but also in the agricultural and social sectors, especially for CH₄.

Restore Earth's capacity to absorb CO₂ by reforestation and afforestation. Although this will take some time considerable, amounts of CO₂ can be fixated.

Adapt to potential effects of climate change. Although it is not certain what kind of local changes climate change will result, several no-regret options can already be taken, some of them with no or minimal additional financial resources.