Climate change in 60 seconds | The Royal Society

The Royal Society

10 Dec 201401:40

Summary

TLDRThe Earth's surface absorbs sunlight and re-emits it as heat, some of which is trapped by greenhouse gases like carbon dioxide and water vapor. Human activities, particularly burning fossil fuels, have raised atmospheric carbon dioxide levels by 40% since 1900, causing a 0.8°C rise in global temperature. This has led to ocean warming, sea level rise, shrinking snow and ice cover, and Arctic sea ice decline. If emissions continue unchecked, global temperatures could increase by 2.6°C to 4.8°C by the century's end, with significant consequences for both humanity and the environment.

Takeaways

🌞 The sun's rays reach Earth's surface, with some absorbed and re-emitted as heat.
🌍 Greenhouse gases like water vapor and carbon dioxide absorb and re-radiate some of this heat.
📈 An increase in greenhouse gases leads to more heat being trapped, warming the Earth.
🔥 Human activities, particularly burning fossil fuels, have increased atmospheric carbon dioxide by 40% since 1900.
🌡️ Global average surface temperature has risen by 0.8°C over this period.
🌊 Oceans have warmed, contributing to additional climate changes in recent decades.
🌊 Sea levels have risen due to climate change.
❄️ Snow and ice cover in the northern hemisphere has decreased, with a decline in Arctic sea ice.
⚠️ Unchecked emissions could lead to a temperature rise of 2.6°C to 4.8°C by the end of this century.
🚨 Even at the lower end of this temperature increase, there would be serious consequences for human societies and the natural world.

Q & A

What happens to the sun's rays when they reach the Earth's surface?
-Some of the sun's rays are absorbed by the Earth's surface and re-emitted as heat.
What role do greenhouse gases play in trapping heat?
-Greenhouse gases, such as water vapor and carbon dioxide, absorb and re-radiate some of the heat, preventing it from escaping into space.
How have human activities affected the concentration of greenhouse gases?
-Human activities, especially the burning of fossil fuels, have increased atmospheric carbon dioxide concentrations by 40% since 1900.
How much has the global average surface temperature increased since 1900?
-The global average surface temperature has increased by 0.8℃ since 1900.
What other climate changes have occurred in recent decades?
-Recent decades have seen ocean warming, rising sea levels, decreasing snow and ice cover in the northern hemisphere, and a decline in Arctic sea ice.
What are the projected consequences if greenhouse gas emissions continue unchecked?
-If emissions continue unchecked, global warming of 2.6℃ to 4.8℃ is expected by the end of this century.
What impact would even a low-end increase in temperature have?
-Even a low-end temperature increase of 2.6℃ would have serious implications for both human societies and the natural world.
How does the increase in carbon dioxide affect sea levels?
-The increase in carbon dioxide contributes to the warming of the oceans, which causes sea levels to rise due to thermal expansion and melting ice.
What is happening to snow and ice cover in the northern hemisphere?
-Snow and ice cover in the northern hemisphere is decreasing, which contributes to further warming as reflective ice surfaces are replaced by darker, heat-absorbing surfaces.
Where can additional information about climate change be found?
-More information about climate change can be found at royalsociety.org/climatechange or nas-sites.org/americasclimatechoices.

Outlines

00:00

🌞 The Sun’s Energy and Greenhouse Gases

This paragraph explains how the sun’s rays, upon reaching the Earth, are absorbed and re-emitted as heat. Greenhouse gases like water vapor and carbon dioxide play a significant role by absorbing and re-radiating some of this heat back into the atmosphere. The increased concentration of these gases causes more heat to be trapped, leading to a warming Earth.

🔥 Human Impact on Carbon Dioxide Levels

This section highlights how human activities, particularly the burning of fossil fuels, have drastically increased atmospheric carbon dioxide concentrations by 40%, with most of this rise occurring since 1900. The burning of fossil fuels is identified as the primary driver of this increase.

🌡️ Rising Global Temperatures

This paragraph discusses the global average surface temperature increase of 0.8℃ since the rise in carbon dioxide levels began. It suggests that the rising temperatures are a direct consequence of increased greenhouse gases in the atmosphere, pointing to the broader issue of climate change.

🌊 The Effects on Oceans and Ice

This segment identifies several impacts of climate change: the warming of the oceans, rising sea levels, diminishing snow and ice cover in the northern hemisphere, and the significant decline of sea ice in the Arctic. These effects highlight the extent of climate change in recent decades.

🚨 The Consequences of Unchecked Emissions

Here, the paragraph warns that if greenhouse gas emissions continue at their current rate, the Earth’s temperature could rise by an additional 2.6℃ to 4.8℃ by the century's end. Even at the lower end of this projection, the consequences would be severe for both human societies and the natural world.

📚 Where to Learn More About Climate Change

The final paragraph encourages readers to seek more information on climate change from reputable sources, including the Royal Society and the National Academies of Sciences. It provides links to these resources for a deeper understanding of the issue.

Mindmap

Keywords

💡Greenhouse gases

Greenhouse gases, such as water vapor and carbon dioxide, are compounds in Earth's atmosphere that trap heat by absorbing and re-radiating it. In the video, they are key to understanding how human activities, especially the burning of fossil fuels, have led to an increase in these gases, causing the Earth's atmosphere to warm.

💡Carbon dioxide

Carbon dioxide (CO2) is a primary greenhouse gas emitted through human activities, particularly the burning of fossil fuels. The script notes that human activities have increased atmospheric carbon dioxide levels by 40% since 1900, making it a significant contributor to climate change and global warming.

💡Fossil fuels

Fossil fuels, such as coal, oil, and natural gas, are energy sources formed from ancient organic matter. The video highlights that burning fossil fuels is the main cause of increased atmospheric carbon dioxide levels, which accelerates climate change and global warming.

💡Global warming

Global warming refers to the long-term increase in Earth's average surface temperature due to human activities, especially the release of greenhouse gases. The video states that the Earth's surface temperature has increased by 0.8℃ since 1900, largely because of the enhanced greenhouse effect.

💡Sea level rise

Sea level rise is the increase in the average level of the world's oceans, driven by melting ice and the thermal expansion of seawater as it warms. The script identifies rising sea levels as one of the observable effects of climate change, threatening coastal communities and ecosystems.

💡Ocean warming

Ocean warming refers to the increase in the temperature of the ocean's surface waters. The video mentions that the warming of oceans is one of the consequences of climate change, which affects marine life, ocean currents, and weather patterns.

💡Snow and ice cover

Snow and ice cover refers to the layer of frozen water that covers parts of the Earth's surface, including glaciers and ice caps. The video explains that climate change has caused a decrease in snow and ice cover in the northern hemisphere, which contributes to rising sea levels and disrupts ecosystems.

💡Arctic sea ice decline

The decline of Arctic sea ice is the reduction in the area and thickness of ice in the Arctic Ocean. The video highlights this as an important indicator of global warming, showing how higher temperatures are causing the rapid melting of sea ice, with significant impacts on wildlife and global climate systems.

💡Emissions

Emissions refer to the release of substances, particularly greenhouse gases, into the atmosphere. The script warns that if emissions, especially from burning fossil fuels, continue unchecked, the planet could warm by an additional 2.6℃ to 4.8℃ by the end of the century, which would have serious consequences for both human society and the environment.

💡Climate change

Climate change is the long-term alteration of temperature and weather patterns, primarily caused by human activities such as burning fossil fuels. The video discusses the various manifestations of climate change, including global warming, sea level rise, and decreased snow and ice cover, stressing the urgency of addressing these changes.

Highlights

The sun's rays reach Earth's surface, where some are absorbed and re-emitted as heat.

Greenhouse gases like water vapor and carbon dioxide absorb and re-radiate some of this heat.

Increased levels of greenhouse gases in the atmosphere trap more heat, causing global warming.

Human activities, especially fossil fuel burning, have increased atmospheric carbon dioxide by 40% since 1900.

Global average surface temperature has risen by 0.8°C since the start of the 20th century.

Warming of the oceans is a clear indication of recent climate changes.

Sea levels have risen due to climate change, contributing to coastal erosion and flooding.

Snow and ice cover in the northern hemisphere has been decreasing in recent decades.

Arctic sea ice has also declined, a significant indicator of climate change.

If greenhouse gas emissions continue unchecked, further warming of 2.6°C to 4.8°C is expected by the end of this century.

Even the lower estimate of warming would have serious implications for human societies and natural ecosystems.

Higher levels of warming would lead to more drastic impacts on global climate systems.

The effects of climate change are already observable in extreme weather patterns and natural disasters.

Governments and societies need to address greenhouse gas emissions to mitigate the worst impacts of climate change.

For more information, visit royalsociety.org/climatechange or nas-sites.org/americasclimatechoices.