What is Climate Change? Crash Course Geography #14

Summary

The video script discusses the impact of human-induced climate change, particularly the rapid melting of glaciers like Iceland's Okjokull. It emphasizes the global responsibility to address carbon emissions, highlighting corporate and individual contributions. The script explores the science behind climate change, differentiating between climate change and global warming, and discusses the historical context and driving forces behind these changes. It also addresses the disproportionate effects of climate change on different regions and communities, urging collective action for mitigation and adaptation.

Takeaways

• 🧊 The Okjokull glacier in Iceland, which was over 800 years old, was declared dead in 2014 due to climate change.
• 🌍 The loss of Okjokull was commemorated with a plaque in 2019, marking the first monument dedicated to a glacier lost to human-induced global warming.
• ☀️ Rising temperatures correlate with increased carbon dioxide levels in the atmosphere, which are influenced by human activities.
• 🏭 In 2019, about half of the total US emissions were from corporate sources like power plants and oil and gas production facilities, indicating their significant role in emissions.
• 🌱 Individual actions on climate change matter, but the responsibility for emissions is not evenly distributed, with corporations contributing a substantial share.
• 🌍 The Earth's climate is complex, and understanding it involves studying who and what is emitting carbon dioxide and the geographical impacts of a warming planet.
• 📉 Glaciers around the world have dramatically shrunk, with Muir Glacier in Alaska showing significant reduction when compared images from 1941 and 2004.
• 🌡️ Global warming and climate change are closely related but distinct concepts; the former refers to the rise in average temperatures, while the latter involves changes in weather patterns over time.
• 🌿 Climate change can be caused by natural factors or human activities, with the current period of warming largely attributed to human-induced factors.
• 🌍 The Earth's climate has undergone significant changes many times, with ice core data providing evidence of past atmospheric conditions and climate shifts.
• 🌿 Human activities, particularly since the mid-20th century, have caused most of the Earth’s warming, leading to anthropogenic global warming.

Q & A

What significant event occurred at Okjokull glacier in Iceland?

Okjokull glacier, which was around 800 years old, was officially declared dead in 2014 by Icelandic geologist Oddur Sigurðsson. In 2019, a plaque was installed to commemorate its loss, marking the first monument dedicated to a glacier lost to human-induced global warming.

How does the melting of glaciers relate to rising carbon dioxide levels?

Rising temperatures, which are correlated with rising carbon dioxide levels in the atmosphere, cause ice and snow to melt faster. The carbon dioxide generated by human activities can have a global impact, including on glaciers.

What is the difference between climate change and global warming as described in the script?

Climate change refers to the change in average weather patterns in a region over a long period of time, which can be natural or human-induced. Global warming, on the other hand, specifically refers to the increase in the average surface temperature of the planet, primarily due to human activities that increase greenhouse gas emissions.

How do changes in precipitation affect glaciers?

Glaciers depend on the amount of precipitation they receive each year. If less snow accumulates, glaciers lose more ice at their bottom edge than they can replace at the top, leading to a net loss of ice.

What role do hydrosphere and its regional patterns play in glacier dynamics?

The hydrosphere, and its regional patterns, which depend on temperature and wind patterns over distant oceans, influence the amount of precipitation that falls on glaciers. This, in turn, affects the rate of glacier growth or retreat.

What are some of the driving forces behind climate change according to the script?

The driving forces behind climate change include orbital causes, volcanic activity, changes in albedo due to surface reflectivity, impacts from celestial bodies like asteroids, continental and oceanic rearrangements, and changes in greenhouse gases in the atmosphere.

How do ice core data help scientists understand past climates?

Ice core data provide a record of past atmospheric conditions by capturing tiny air bubbles in each layer of ice. Scientists can analyze these bubbles to determine the chemical composition of past atmospheres and estimate climates going back at least 400,000 years.

What is the significance of the 400 parts per million mark for atmospheric carbon dioxide levels?

In 2016, global atmospheric carbon dioxide levels passed the 400 parts per million mark, which is higher than at any time in the past million years. This indicates an enhancement of the natural greenhouse effect, leading to more heat being trapped in the lower atmosphere and contributing to global warming.

Why are materially rich countries and materially poorer countries affected differently by climate change?

Materially rich countries are often the main producers of greenhouse gas emissions, while materially poorer countries are more likely to bear the impacts of climate change, such as becoming climate refugees or facing threats from rising sea levels, due to their geographical vulnerabilities and lack of resources to adapt.

What actions can individuals and societies take to address human-induced climate change?

Individuals can make a difference through personal choices, while corporations and governments need to be held responsible for their policies and large-scale emissions. Reducing emissions, adapting to changes, and integrating solutions into society are key actions to mitigate the effects of climate change.