glaciers melting

Glaciers Melting: Why Earth Depends On Ice

Jane Marsh - February 25, 2023

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Anyone who drinks water, eats seafood, or lives on land should care about glaciers melting. The impact of melting glaciers and icebergs has a ripple effect that reaches every inch of the planet. From food supplies to shrinking shorelines and even the history of the planet, here’s a look at why Earth and humanity depend on ice. 

Glaciers Melting and Exponential Warming

Most people have heard the stories of glaciers melting in Antarctica and seen the pictures of polar bears slowly losing their habitats. The issue of glaciers melting is much bigger than many people realize, though. It goes far beyond the loss of snowy environments for polar bears and penguins. The Earth itself needs glaciers and has relied on them for millennia. 

Glaciers play a critical role in the way our planet handles heat. It may sound ironic, but the world’s icy regions actually get a lot of sunlight. Since they are covered in white ice and snow, though, the sunlight is reflected back into space rather than absorbed. Glaciers act as a heat mirror for the planet, similar to the shiny foil covers people put in their car windshields to keep out heat. 

So, as the glaciers diminish in size due to melting, there is less white surface area to reflect heat away from the planet. As a result, more heat is absorbed by the surrounding ocean water. That warm water then helps melt the glaciers even more, speeding up a vicious cycle. Ultimately, the result is exponentially melting glaciers and exponentially rising temperatures. 

Those rising temperatures don’t just make for a balmy summer for the polar bears, either. Glaciers are the heat mirror for the whole planet. As they melt and keep out less heat, the entire planet will heat up more. 

Water, Currents, and Flooding

Glaciers melting results in accelerating global warming, but why should the average person be concerned about that? A lot of people wouldn’t mind warmer winters, after all. There are a number of negative side effects that occur when glaciers melt, which can dramatically change the entire planet, including human civilization. 

It is important to remember that glaciers are essentially giant ice cubes. Glaciers are caps of ice frozen on top of solid ground while icebergs are islands of ice floating at sea. Both are melting today. Both contain massive amounts of frozen water. 

The world’s largest glacier, the Lambert Glacier in Antarctica, is 250 meters long, almost as wide as the state of New York. It is also 2,500 meters deep. That is a monumental amount of ice and it’s all in just one glacier. It is worth keeping in mind that water molecules contract when they freeze into solid ice, so when ice melts into liquid water, it actually expands to take up more volume than it does when frozen. 

Shrinking Shorelines

This means that if the world’s glaciers all melted, it would release an enormous amount of water into Earth’s oceans. Humans would notice, too. Scientists estimate that if all of the world’s glaciers and ice sheets completely melted away one day, the world’s sea level would rise almost 200 feet in total. That’s equivalent to the height of an average 14-storey building. Such a change in sea level would take decades, but would dramatically reshape our planet in the process. 

As sea level rises, shorelines shrink inland, reducing the amount of dry land not covered by ocean water. This alone should concern humans, since we need dry land to live on and, equally importantly, farm on. Less land means less space for the agricultural resources the human population relies on for food. 

Keep in mind, as mentioned above the glaciers melting would result in an accelerating rise in global temperatures. So, while farmable land is shrinking in size due to sea level rise, temperatures are also getting warmer. In some regions, this will result in significant severe weather and flooding. In other areas, the opposite will happen, with regions like the American Southwest experiencing crippling droughts due to accelerated evaporation. 

Both severe weather and droughts will further endanger global food supplies due to lack of sufficient farmable land. In fact, glaciers melting will even impact the amount of drinking water available to humans. Our freshwater supply relies in part on runoff from glaciers as they slowly melt each year. A little bit of melting and refreezing is normal. If all glaciers completely melted away, though, those supplies of drinkable runoff water would disappear. 

Impact On Wildlife

Anyone who enjoys eating sushi or fish should be concerned about glaciers melting. As of 2017, fish are estimated to account for nearly 20% of animal proteins consumed by humans. The fish that make up a large portion of the global food supply are part of a fragile ecosystem reliant on fragile environments. Glaciers melting would cause irreparable damage to the world’s ocean habitats. 

For example, sea level rise would result in less sunlight reaching previously shallow parts of the ocean, including coral reefs. The world’s reefs are rich ecosystems that support thousands of species. Without adequate sunlight, though, reef life would die off. This alone would cause a ripple effect throughout the entire ocean. We are already seeing the impact of dying reefs today due to coral bleaching caused by climate change. As species die off, other species lose their food sources. Ultimately, this leads to humans losing our food sources. 

Additionally, the world’s oceans would all heat up. With no ice to help keep the planet cool or provide streams of chilled water in ocean currents, temperatures would go up in all ocean regions. This change in temperature would further damage marine ecosystems, since ocean plants and animals have evolved to survive in specific conditions. 

The End of Ice Ages

Finally, it is worth understanding the long-term impact of glaciers melting. The problem isn’t just about a little less ice and land for humans. Melting glaciers cause chaos in marine ecosystems, diminish livable and farmable land for humans, and impact the availability of food and drinking water. The exponential heating caused by climate change and melting glaciers is so severe that it is reshaping the natural climate cycles of our planet. 

Earth has gone through an estimated five separate ice ages. These are periods that are the opposite of what we are experiencing now – the growth of glaciers causes exponential cooling. There are a number of factors that trigger ice ages, including the position of the Earth relative to the Sun. However, human activity has caused such severe emissions that the next ice age has been delayed by an estimated 50,000 years. 

To put that into perspective, interglacial periods, one of which we are in now, are only supposed to last about 10,000 to 20,000 years. The last ice age had a profound impact on Earth. As glaciers eroded rocks and moved over the Earth, they spread nutrients from the ground and formed rivers and lakes. These side effects of the last ice age helped early humans thrive in prehistoric times, giving rise to civilization as we know it today. 

Humans have survived on Earth for millions of years, through multiple ice ages and interglacial periods. However, industrialization from just the last few hundred years has devastated our planet’s normal climate mechanisms to such a degree that we have forever altered the course of history for everything on Earth. Glaciers melting are a warning of the long-term damage that climate change could cause if humans don’t do something to fix what we started. 

Glaciers Melting: A Global Challenge

Glaciers melting aren’t just a biodiversity issue or an arctic issue or a biology issue. Melting glaciers are causing a domino effect of powerful changes all over our planet that could potentially devastate life on land and water alike if something does not change. Luckily, there are people all over the world developing new technologies and policies that will help repair our climate and slow glacial melting.

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About the author

Jane Marsh

Starting from an early age, Jane Marsh loved all animals and became a budding environmentalist. Now, Jane works as the Editor-in-Chief of Environment.co where she covers topics related to climate policy, renewable energy, the food industry, and more.