Greenland Lakes and Climate Change

In 2022, over 7,500 lakes in western Greenland underwent drastic changes. These lakes, once known for their clear blue waters, began emitting carbon and deteriorating in water quality. A recent study published in the *Proceedings of the National Academy of Sciences* marks the rapid transformation of these lakes following extreme weather events. The changes occurred within months rather than over centuries, marking an unprecedented shift.

Extreme Weather Events

In late 2022, warmer temperatures caused snowfall to turn into rain. This unusual weather pattern was driven by atmospheric rivers. These are narrow regions in the atmosphere that transport amounts of water vapour. The increased rainfall led to the thawing of permafrost, releasing organic carbon and other elements into the lakes.

Impact on Lake Properties

As the elements washed into the lakes, their physical, chemical, and biological properties changed. The lakes’ colour, odour, and taste altered by July 2023. The increased organic material affected drinking water treatment processes, leading to potentially carcinogenic byproducts.

Effects on Phytoplankton

The transformation of the lakes reduced sunlight penetration. This adversely affected phytoplankton, which play important role in carbon dioxide absorption through photosynthesis. With less light, the phytoplankton’s ability to consume carbon dioxide diminished.

Carbon Emissions Increase

The lakes transitioned from being carbon sinks to sources of carbon dioxide. Emissions from these lakes rose by 350%. This shift is alarming as it contributes to the overall increase in atmospheric carbon levels.

Global Context

The findings coincide with another study indicating a collapse in carbon absorption by terrestrial ecosystems. In 2023, forests and soils absorbed less carbon than in previous years. As natural carbon sinks weaken, atmospheric carbon levels are expected to rise sharply, exacerbating climate change.

Future Projections

Climate models predict that atmospheric rivers will become more frequent and intense by the end of the 21st century. This will likely affect regions beyond Greenland, including western North America and eastern Asia. The implications of these changes are deep for global climate patterns and biodiversity.

Significance of the Study

This study sheds light on the rapid impacts of climate change on freshwater ecosystems. It puts stress on the urgent need for climate action. The transformation of Greenland’s lakes serves as a warning of the broader consequences of rising temperatures and changing weather patterns.

Questions for UPSC:

1. Discuss the significance of atmospheric rivers in global climate patterns.
2. Explain the role of phytoplankton in carbon cycling and its implications for climate change.
3. Critically examine the impact of climate change on freshwater ecosystems and biodiversity.
4. With suitable examples, discuss the relationship between permafrost thawing and greenhouse gas emissions.

Answer Hints:

1. Discuss the significance of atmospheric rivers in global climate patterns.

1. Atmospheric rivers are narrow bands of moisture in the atmosphere that transport large amounts of water vapor, influencing precipitation patterns.
2. They contribute to freshwater supplies in various regions but can also lead to extreme weather events like flooding.
3. With climate change, atmospheric rivers are projected to become more intense and frequent, impacting weather systems globally.
4. They play important role in redistributing heat and moisture, affecting temperature and precipitation patterns across continents.
5. About atmospheric rivers is essential for predicting climate impacts and managing water resources effectively.

2. Explain the role of phytoplankton in carbon cycling and its implications for climate change.

1. Phytoplankton are microscopic organisms that perform photosynthesis, absorbing carbon dioxide from the atmosphere and producing oxygen.
2. They act as carbon sink, sequestering carbon in oceanic and freshwater systems.
3. Changes in light availability, such as those caused by lake transformations, can diminish phytoplankton’s ability to absorb CO2.
4. Reduced phytoplankton populations can lead to increased atmospheric carbon levels, exacerbating climate change.
5. Maintaining healthy phytoplankton populations is vital for global carbon cycling and mitigating climate impacts.

3. Critically examine the impact of climate change on freshwater ecosystems and biodiversity.

1. Climate change alters temperature and precipitation patterns, affecting the physical and chemical properties of freshwater bodies.
2. Changes in water quality, such as increased organic material and altered nutrient levels, can harm aquatic life and biodiversity.
3. Freshwater ecosystems are sensitive to temperature changes, which can lead to species migration, population declines, and loss of biodiversity.
4. Extreme weather events can disrupt breeding cycles and habitat availability for aquatic species.
5. Protecting freshwater ecosystems is essential for maintaining biodiversity and ensuring clean water supplies for communities.

4. With suitable examples, discuss the relationship between permafrost thawing and greenhouse gas emissions.

1. Permafrost is a layer of permanently frozen soil that contains large amounts of organic carbon; thawing releases this carbon as greenhouse gases.
2. As temperatures rise, thawing permafrost contributes to increased emissions of carbon dioxide and methane, potent greenhouse gases.
3. Examples include the Siberian tundra, where thawing has led to methane emissions, intensifying climate change effects.
4. Thawing permafrost can also destabilize landscapes, affecting infrastructure and ecosystems, leading to further emissions.
5. Mitigating permafrost thawing is crucial for reducing greenhouse gas emissions and combating climate change.