Le changement climatique, un constat ! MaP#10

Le Réveilleur

26 Sept 201512:03

Summary

TLDRThis episode of Mise au Point addresses climate change, explaining its distinction from global warming. The host emphasizes the rise in average global temperatures and other climate variations, including precipitation changes, desertification, and increased flooding. The video highlights the overwhelming scientific consensus on human-driven climate change, contrasting this with public skepticism, often fueled by political and economic interests. It stresses the urgency of understanding climate science and addressing misinformation, encouraging viewers to engage with the issue. Future episodes will delve deeper into the physical mechanisms behind climate change.

Takeaways

🌡️ Climate change refers to long-term shifts in global temperatures, including both warming and cooling trends.
🌍 Global warming specifically denotes the long-term increase in Earth's average surface temperature, while climate change encompasses a broader range of shifts including precipitation patterns and extreme weather events.
🌊 Oceans play a critical role in climate change by absorbing a significant amount of excess heat, leading to thermal expansion and contributing to sea-level rise.
🏔️ The melting of ice, particularly in Greenland, is a visible indicator of climate change, with billions of tons of ice loss annually equating to the weight of over 28 million Eiffel Towers.
🌳 Climate change impacts extend to ecosystems, affecting the distribution of plant and animal species, as well as causing desertification and altering precipitation patterns.
🔍 The scientific consensus is clear: 97% of scientists agree that climate change is real and largely a result of human activities, despite a gap between this consensus and public perception.
🌐 The Intergovernmental Panel on Climate Change (IPCC) synthesizes scientific findings to inform policymakers and the public, reinforcing the scientific consensus on human-induced climate change.
🏛️ There is a significant disconnect between the scientific community's understanding of climate change and the public's perception, influenced in part by misinformation spread by certain media, corporations, and political groups.
💼 Economic interests, particularly in the fossil fuel industry, have been identified as a driving force behind climate change denial, as acceptance of climate change challenges their profitability.
🌱 Addressing climate change requires societal changes, including shifts in consumption, energy production, and transportation, emphasizing the need for collective action and policy changes to mitigate its impacts.

Q & A

What is the difference between 'global warming' and 'climate change' as explained in the script?
-'Global warming' refers specifically to the rise in average temperatures of the Earth's oceans and atmosphere. 'Climate change' is a broader term that includes changes in weather patterns, such as alterations in precipitation, increased frequency of droughts and floods, and desertification, beyond just temperature increases.
Why do scientists prefer to use the term 'climate change' rather than 'global warming'?
-Scientists prefer 'climate change' because it encompasses a wider range of phenomena, not just temperature increases. This term includes changes in precipitation patterns, ocean levels, and the frequency of extreme weather events, which are all crucial aspects of the changing climate.
How do oceans contribute to the global warming process?
-Oceans absorb a significant amount of the excess energy from global warming due to their large thermal capacity. They warm up more slowly than the atmosphere, but they store much more energy, contributing to long-term climate change impacts.
What is the significance of thermal expansion in the context of rising sea levels?
-Thermal expansion refers to the increase in water volume as it warms. This process is responsible for more than half of the observed rise in sea levels, alongside melting glaciers and ice sheets.
How much ice is Greenland losing annually due to climate change?
-Greenland is losing approximately 287 billion tons of ice per year, which is equivalent to the weight of over 28 million Eiffel Towers.
What is the scientific consensus on the human contribution to climate change?
-The vast majority (97%) of climate scientists agree that climate change is real and largely caused by human activities, such as the burning of fossil fuels and deforestation.
Why is there a significant gap between scientific consensus and public opinion regarding climate change?
-The gap is largely due to misinformation spread by certain industries and political groups that have economic interests in maintaining fossil fuel consumption. This disinformation has led to confusion and skepticism among the public, despite the overwhelming scientific evidence.
What role do industries like oil and gas play in promoting climate skepticism?
-Industries such as oil and gas, particularly companies like ExxonMobil and Koch Industries, have a vested interest in denying climate change because it threatens their business models. These companies fund climate change denial movements to delay societal recognition and regulation of their activities.
What does the speaker suggest is necessary to bridge the gap between scientific understanding and public perception of climate change?
-The speaker emphasizes the need for better public education on climate science and increased dissemination of factual information. They suggest that clear communication and public outreach, including sharing scientifically backed content, can help bridge this gap.
Why is understanding climate change important for society, according to the speaker?
-Climate change has direct consequences on society, such as altering energy consumption, production methods, and transportation. It also has political implications, as acknowledging climate change challenges certain economic systems. Understanding it is essential for shaping policies and preparing for future societal impacts.

Outlines

00:00

🌍 Introduction to Climate Change

The video introduces the concept of climate change, distinguishing between terms like 'global warming' and 'climate change.' While global warming refers to the increase in average temperatures of oceans and the atmosphere, climate change encompasses various phenomena, such as changes in precipitation, desertification, and increased frequency of natural disasters like floods and droughts. The presenter chooses to focus on the broader term, 'climate change,' for a more comprehensive view. There is also a discussion on the scientific consensus around climate change and its strong connection to human activities.

05:00

📈 Scientific Data on Rising Temperatures

The paragraph delves into the empirical evidence of rising global temperatures. It emphasizes that the increase is observed over decades and averages across the planet. This section also highlights that temperature variations are not uniform across regions or timeframes. The video includes a NASA-provided visualization, showcasing the temporal and spatial temperature changes, particularly over oceans, which store significant amounts of excess energy. The rising ocean temperatures are also linked to rising sea levels, due to both ice melting and thermal expansion.

10:03

❄️ Glacial Melting and Sea-Level Rise

The paragraph focuses on the melting of glaciers, especially in Greenland, which loses 287 billion tons of ice annually. This loss is quantified by comparing it to the weight of 28 million Eiffel Towers. The melting glaciers contribute to sea-level rise, which is exacerbated by the thermal expansion of the oceans. The section also references various indicators of climate change, such as changes in precipitation patterns and increased occurrences of droughts and floods.

📊 Scientific Consensus and Public Opinion

This paragraph addresses the overwhelming scientific consensus that climate change is driven by human activity. It mentions the role of the IPCC (Intergovernmental Panel on Climate Change) in synthesizing climate research for policymakers and the general public. However, there is a stark contrast between scientific understanding and public perception, with a significant portion of the population still skeptical, especially in countries like the United States and France. The presenter aims to bridge this gap by educating the public on the realities of climate change.

🔬 Science, Politics, and Climate Change

Here, the focus shifts to the politicization of climate change. The presenter notes how economic and political interests, particularly in industries reliant on fossil fuels, fund climate change skepticism. Companies like ExxonMobil and Koch Industries are mentioned as key players delaying climate action for economic gain. The presenter criticizes this disinformation campaign, which works against societal interests and future well-being, calling for open discussion to promote truth and awareness.

🚨 Urgent Call to Address Climate Change

This concluding paragraph is an urgent call to action. The presenter emphasizes that denying climate change is like driving toward a wall and closing your eyes, hoping it will disappear. The need to confront the reality of climate change before it's too late is stressed, and the video is framed as an introduction to a more in-depth exploration of climate science. The presenter also encourages viewers to share the video and engage in dialogue to spread awareness.

Mindmap

Keywords

💡Climate Change

Climate change refers to long-term shifts in temperatures and weather patterns. It is not just about temperature changes but includes phenomena like altered precipitation, desertification, and increased frequency of floods and droughts. In the video, climate change is the central theme, with the script emphasizing that these changes are part of a broader pattern of modifications to our climate.

💡Global Warming

Global warming is the long-term increase in Earth's average surface temperature due to human activities such as fossil fuel burning and deforestation. The script uses the term to describe the observed rise in global average temperatures over several decades, which is a key indicator of climate change.

💡Temperature Anomalies

Temperature anomalies are deviations from the average temperature. The video script discusses how these anomalies have been observed and averaged over the globe, indicating a warming trend. It mentions a NASA video showing temperature variations from blue (cooler) to red (warmer), illustrating the spatial and temporal changes.

💡Ocean Heat Content

Ocean heat content refers to the thermal energy stored in the ocean. The script explains that oceans absorb a significant amount of heat due to their large heat capacity, which is much greater than that of the atmosphere or land. This concept is crucial for understanding how global warming works since oceans play a major role in moderating climate.

💡Sea Level Rise

Sea level rise is the increase in the height of the average sea surface. The video mentions sea level rise as a consequence of both the melting of ice and the thermal expansion of oceans. The script provides an example of how thermal expansion alone accounts for more than half of the observed sea level rise.

💡Glacier Mass

Glacier mass refers to the amount of ice contained within a glacier. The script uses the example of Greenland's glaciers to illustrate how the mass of glaciers is decreasing, with Greenland losing billions of tons of ice annually, which is a significant indicator of climate change.

💡Precipitation Patterns

Precipitation patterns are the distribution and frequency of rainfall or other forms of precipitation. The video script discusses how climate change affects these patterns, leading to more droughts and floods in different regions. This is an important aspect of climate change as it impacts agriculture, water resources, and ecosystems.

💡Desertification

Desertification is the process by which fertile land becomes desert, typically as a result of drought, deforestation, or inappropriate agricultural practices. The script mentions desertification as one of the phenomena associated with climate change, indicating how it can lead to land degradation and loss of habitat.

💡Scientific Consensus

Scientific consensus refers to the collective judgment, position, and opinion of the scientific community on a particular subject. The script emphasizes the overwhelming agreement among scientists that climate change is real and largely caused by human activities, contrasting this with public opinion that may be influenced by misinformation.

💡Climate Sceptics

Climate sceptics are individuals or groups who question the scientific consensus on climate change. The script discusses how even the most vehement sceptics have shifted their focus from denying climate change to disputing the link between human activities and climate change, reflecting a change in the nature of the debate.

💡Anthropogenic

Anthropogenic means caused by human activity. In the context of the video, anthropogenic climate change refers to the role of human activities in causing climate change. The script argues that there is a well-established scientific theory supporting the idea that human activities, such as burning fossil fuels, are significantly contributing to climate change.

Highlights

Climate change refers to the long-term shifts in temperatures and weather patterns on Earth.

Global warming is a part of climate change, indicating an increase in the average temperatures of oceans and the atmosphere.

Climate change includes phenomena like changes in precipitation, desertification, and increased frequency of floods and droughts.

The scientific community widely agrees on the human-induced nature of climate change.

The video provides a visual representation of global temperature changes over time.

Oceans are warming and accumulating a significant amount of heat energy.

Sea level rise is attributed to both melting ice and thermal expansion of oceans.

Greenland's glaciers are losing mass, with a current annual loss of 287 billion tons of ice.

Climate change indicators include changes in precipitation patterns, frequency of droughts and floods, and shifts in species distribution.

Despite the scientific consensus, there is a gap between public perception and the reality of climate change.

97% of scientists agree that climate change is real and caused by human activities.

Public opinion varies, with a significant portion of the population being climate change skeptics.

The video addresses the economic and political implications of climate change.

Some industries fund climate change denial to protect their economic interests.

The video emphasizes the importance of acknowledging and addressing climate change for the future of society.

The speaker calls for a reduction in the gap between scientific understanding and public perception of climate change.

The video serves as an introduction to a series that will delve deeper into the science behind climate change.