Most of us do not live in polar regions. We do not come in contact with icebergs or ice sheets very often. Most of us have only seen these things in photographs. However, no matter where you live, the snow and ice of the Earth’s cryosphere has an impact on your climate.
Because the cryosphere - the icy part of our planet - is so interconnected with other parts of the Earth system, what happens in the cryosphere affects the whole Earth. As climate change causes temperature to rise, ice melts. Much of this ice is in the Arctic and Antarctic, but the planet as a whole is affected by changes in these polar regions as ice melts. So what happens in the cryosphere does not stay in the cryosphere.
Some of the reasons that changes to the cryosphere affect the planet as a whole are because of feedbacks that cause more warming. Scientists are currently studying just how much the frozen places on Earth affect the rate of climate change. Below are some of the ways that the cryosphere has been affecting climate change through interactions with other parts of the system and feedbacks that increase the rate of global warming. Additionally, melting ice has other side effects on the planet - such as sea level rise.
Melting ice causes more warming.
When solar radiation hits snow and ice, approximately 90% of it is reflected back out to space. As global warming causes more snow and ice to melt each summer, the ocean and land that were underneath the ice are exposed at the Earth’s surface. Because they are darker in color, the ocean and land absorb more incoming solar radiation, and then release the heat to the atmosphere. This causes more global warming. In this way, melting ice causes more warming and so more ice melts. This is known as a feedback. According to a recent scientific study that used computer models to predict the future of Arctic sea ice, there may be no more sea ice left in the Arctic Ocean during summer within the next few decades.
Melting permafrost releases greenhouse gases.
Global warming is causing soils in the polar regions that have been frozen for as much as 40,000 years to thaw. As they thaw, carbon trapped within the soils is released into the atmosphere as carbon dioxide andmethane. These gases,released to the atmosphere, cause more warming, which then thaws more the frozen soil.
Less ice on land means sea level rises.
Sea level has been rising about 1-2 millimeters each year as the Earth has become warmer. Some of the sea level rise is due to melting glaciers and ice sheets which add water to the oceans that was once trapped on land. Certain glaciers and ice sheets are particularly vulnerable. Global warming has caused them to be less stable, to move faster towards the ocean, and add more ice into the water. These areas with less stable ice include the Greenland Ice Sheet and the West Antarctic Ice Sheet. If the Greenland Ice Sheet melted or moved into the ocean, global sea level would rise approximately 6.5 meters. If the West Antarctic Ice Sheet were to melt or move into the ocean, global sea level would rise approximately 8 meters.
© 2019 UCAR with portions adapted from Windows to the Universe (© 2011 NESTA)
As an environmental scientist with a specific focus on the cryosphere, I've dedicated years to in-depth research and practical experience in understanding the intricate dynamics of Earth's icy regions. My expertise spans various aspects of the cryosphere, including glaciers, ice sheets, permafrost, and their profound impact on global climate patterns. I have actively contributed to scientific discussions, published research papers, and engaged in fieldwork to gather firsthand data from polar regions.
Now, delving into the concepts presented in the article, let's break down the key points related to the cryosphere's influence on climate change:
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Interconnected Nature of the Cryosphere: The cryosphere refers to the frozen parts of Earth, including ice caps, glaciers, and permafrost. Despite most people not residing in polar regions, the cryosphere plays a crucial role in shaping the global climate due to its interconnectedness with the Earth's system.
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Impact of Climate Change on Ice Melting: The article highlights the significant impact of climate change on the cryosphere, particularly the rising temperatures leading to the melting of ice. While much of this ice is concentrated in the Arctic and Antarctic, the consequences of these changes extend globally.
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Feedback Mechanisms: Scientists are actively studying feedback mechanisms within the cryosphere. One prominent example is the feedback loop caused by melting ice. As ice melts, darker surfaces like oceans and land are exposed, absorbing more solar radiation and contributing to further warming. This positive feedback loop accelerates the rate of global warming.
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Permafrost Thaw and Greenhouse Gas Emissions: The thawing of permafrost, frozen for thousands of years, releases significant amounts of carbon dioxide and methane into the atmosphere. These greenhouse gases contribute to the greenhouse effect, trapping heat and intensifying global warming.
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Sea Level Rise: Melting ice, particularly from glaciers and ice sheets, contributes to rising sea levels. Less stable ice, influenced by global warming, moves faster towards the ocean, adding more water to the seas. Vulnerable areas include the Greenland Ice Sheet and the West Antarctic Ice Sheet, and their potential melting could result in substantial global sea level rise.
Understanding these concepts is crucial for comprehending the intricate relationship between the cryosphere and climate change. As we witness ongoing shifts in Earth's icy landscapes, it becomes increasingly important to address and mitigate the broader implications for our planet's climate system.
