ClassX Video Lessons Arctic amplification: How the albedo effect speeds up global warming | Jon Gertner
The Arctic is heating up much faster than the rest of the world. This is called “Arctic amplification.” Since the pre-industrial era, the Arctic’s temperature has gone up by about 2 degrees Celsius, while the global average increase is only 1 degree Celsius. This rapid warming is especially noticeable in places like Greenland and Siberia.
One of the biggest problems caused by this warming is the huge drop in Arctic sea ice over the last 20 years. This ice floats on the ocean around the North Pole and has shrunk by about one-third to one-half. Losing this ice is one of the most significant changes to Earth’s environment since humans have been around.
When the ice melts, it changes how the Earth reflects sunlight. Normally, ice reflects sunlight back into space, but when it melts, the dark ocean water absorbs the sunlight instead. This makes the Earth warmer, causing even more ice to melt. Right now, the amount of ice melting in the summer is breaking records, with ice levels hitting new lows by late August.
Melting sea ice doesn’t raise sea levels, just like ice melting in a glass doesn’t make the water overflow. However, the melting of the Greenland ice sheet is different. When it melts, it adds water to the ocean, which raises sea levels and increases the risk of flooding. This is also happening in Antarctica, where ice loss is a big concern for global sea levels.
Greenland’s ice sheet is very sensitive to feedback loops, similar to those affecting Arctic sea ice. As the ice melts, it gets lower, making it warmer and melting even faster. Scientists have noticed that the ice sheet is getting darker, especially in the west. This is due to less snow, the growth of algae, and carbon soot settling on the ice.
When scientists visit Greenland, they see that some areas look snowy, but many parts, especially in the west, are covered in dark, dirty ice. A British research team called “Black and Bloom” is studying this and found that algae and bacteria are thriving on the ice sheet during the summer.
The darker the ice gets, the more sunlight it absorbs, which speeds up melting. This creates a cycle: as the ice gets darker, it melts faster, and as it melts, it gets even darker. This feedback loop is a big problem because the more Greenland melts, the more it will continue to melt.
The warming Arctic and the changes in sea ice and ice sheets are serious environmental issues. The feedback loops they create not only threaten the Arctic but also have major effects on global sea levels and climate stability. It’s crucial to take action to address these challenges and reduce the impacts of climate change.
Conduct a simple experiment to understand Arctic amplification. Use two bowls: one filled with ice and the other with dark-colored water. Place them under a lamp and measure the temperature change over time. Discuss why the bowl with water heats up faster and relate this to the Arctic’s warming.
Create a simulation using a shallow tray filled with water and floating ice cubes. Observe what happens when the ice melts. Discuss how this relates to the decline of Arctic sea ice and its impact on global temperatures.
Build a model using a container to represent the ocean and add ice to one side to represent Greenland’s ice sheet. As the ice melts, measure the change in water level. Discuss how this demonstrates the impact of melting ice sheets on sea levels.
Participate in a role-play activity where you act out the feedback loops in Greenland. Assign roles such as ice, sunlight, algae, and scientists. Discuss how each role contributes to the cycle of melting and its effects on the environment.
Research a specific aspect of the Arctic’s warming, such as the role of algae on ice or the impact on wildlife. Prepare a short presentation to share your findings with the class, highlighting the importance of addressing climate change.
Arctic – The region around the North Pole, characterized by cold temperatures and ice-covered seas. – The Arctic is experiencing significant changes due to rising global temperatures.
Amplification – The process of increasing the strength or intensity of a phenomenon, often used in the context of climate change to describe how certain effects can become more pronounced. – Arctic amplification refers to the rapid warming of the Arctic region compared to the rest of the planet.
Ice – Frozen water, commonly found in polar regions and as glaciers, which plays a crucial role in Earth’s climate system. – The melting of polar ice is contributing to rising sea levels worldwide.
Melting – The process of a solid substance turning into a liquid, often used to describe the thawing of ice due to increased temperatures. – The melting of glaciers is a clear indicator of climate change.
Sea – A large body of saltwater that covers most of the Earth’s surface and is vital for climate regulation. – Changes in sea temperatures can have significant impacts on marine life and weather patterns.
Levels – The height or amount of something, often used to describe the height of the sea surface relative to land. – Rising sea levels pose a threat to coastal communities around the world.
Feedback – A process in which the output or result of a system influences the operation of the system itself, often used in climate science to describe how changes can accelerate or decelerate further changes. – The melting of ice leads to less sunlight being reflected, which is a positive feedback that accelerates warming.
Climate – The long-term pattern of weather conditions in a particular region, including temperature, precipitation, and wind. – Scientists study climate to understand how it is changing over time and affecting ecosystems.
Environment – The natural world, including the air, water, and land in which living organisms exist and interact. – Protecting the environment is crucial for maintaining biodiversity and human health.
Warming – The increase in Earth’s average surface temperature due to human activities, such as burning fossil fuels. – Global warming is causing more frequent and severe weather events around the world.
