Climate Change and Its Effects

The video explains how the sun's rays are absorbed and re-emitted as heat, with greenhouse gases like water vapor and carbon dioxide trapping this heat, leading to global warming. Human activities, particularly fossil fuel burning, have increased atmospheric carbon dioxide by 40% since 1900, raising global temperatures by 0.8℃. Recent climate changes include ocean warming, sea level rise, and reduced ice cover. If emissions remain unchecked, further warming of 2.6℃ to 4.8℃ is expected by century's end, impacting societies and nature. For more information, visit royalsociety.org/climatechange or nas-sites.org/americasclimatechoices.

What happens to some of the sun's rays when they reach the Earth's surface?

• They are absorbed and re-emitted as heat.

• They are converted into wind energy.

• They are absorbed by the oceans only.

• They are reflected back into space.

Which gases are primarily responsible for trapping heat in the atmosphere?

• Hydrogen and helium

• Methane and ozone

• Oxygen and nitrogen

• Water vapour and carbon dioxide

By what percentage have human activities increased atmospheric carbon dioxide since 1900?

• 30%

• 40%

• 50%

• 20%

What has been the increase in global average surface temperature since 1900?

• 1.5℃

• 0.8℃

• 0.5℃

• 1.2℃

What is the expected range of further warming by the end of this century if emissions continue unchecked?

• 1.0℃ to 2.0℃

• 4.0℃ to 6.0℃

• 2.6℃ to 4.8℃

• 3.0℃ to 5.0℃