When people search for information about climate change, Iceland offers some of the clearest and most visible examples of a warming world. Home to some of Europe’s largest glaciers, the country provides a firsthand look at how rising temperatures are reshaping ice, mountains, rivers and coastal landscapes.

These changes are particularly noticeable around Vatnajökull, where outlet glaciers are retreating, new lagoons are forming and familiar glacier features can change from one season to the next. For those of us who work on the glacier throughout the year, these are not simply changes described in scientific reports—they are changes we observe directly.

At Local Guide of Vatnajökull, our team has guided visitors across the region’s glaciers since 1991. Through guided glacier hiking and seasonal ice cave tours, we help visitors explore this constantly changing environment while learning how glaciers form, move, retreat and shape the surrounding landscape.

Climate change is happening across the globe, but few places demonstrate its effects as clearly as Iceland. Understanding what is happening here can help us better understand the wider changes facing glaciers and communities around the world.

What Is Climate Change?

Climate change refers to long-term changes in the Earth’s temperatures and weather patterns. Scientists monitor the climate over many decades because individual weather events do not represent long-term trends.

Throughout the Earth’s history, natural processes such as changes in solar activity and major volcanic eruptions have caused periods of warming and cooling over thousands or even millions of years. However, since the Industrial Revolution in the 18th century, human activity has become the primary driver of climate change.

The main cause is the burning of fossil fuels such as coal, oil and natural gas. These activities release carbon dioxide (CO₂) and other greenhouse gases into the atmosphere. Like a blanket wrapped around the Earth, these gases trap heat and cause global temperatures to rise.

The warming may seem small on paper, but its effects can be seen almost everywhere on Earth.

Climate Change Around the World

Over the 20th century, the Earth’s average surface temperature increased by approximately 0.8°C, with even greater warming in Arctic regions.

This increase in temperature is already having widespread consequences, including:

• Melting glaciers and sea ice

• Rising sea levels

• Changes in vegetation and ecosystems

• Shifting migration patterns of birds and wildlife

Climate change is also making many extreme weather events more frequent or intense. Floods, heatwaves, droughts and wildfires are becoming increasingly common in many parts of the world.

These changes threaten food production, increase risks in vulnerable regions and are expected to displace millions of people as weather-related disasters become more severe. As resources become scarcer, both people and wildlife may face increasing competition for water, land and food.

Here in Iceland, these global changes are impossible to miss. Glaciers have shaped the country’s landscapes for thousands of years, and today they are among the clearest indicators of a warming climate.

Iceland: A Country Shaped by Ice

Around 10% of Iceland is covered by glaciers, making them one of the country’s defining natural features. Unfortunately, Iceland’s glaciers are retreating rapidly as temperatures continue to rise.

Several smaller glaciers have already disappeared entirely. One of the best-known examples is Okjökull in western Iceland, which officially lost its status as a glacier in 2014. The next glacier expected to disappear is Hofsjökull Eystri, a small glacier in eastern Iceland.

This is not only an Icelandic story. The same process is affecting glaciers around the world.

How Do Glaciers Form?

To understand why glaciers are shrinking, it helps to understand how they form in the first place.

Glaciers develop when more snow accumulates each year than melts during the summer. Over time, the accumulated snow is compressed into dense glacial ice.

It might seem impossible, but glaciers are constantly moving. As a glacier grows thicker, the immense weight of the ice causes it to deform. Rather than behaving like a completely rigid solid, glacier ice slowly flows downhill, somewhat like very thick caramel.

While new ice continues to form high in the mountains, warmer temperatures at lower elevations cause the glacier to melt.

For glaciers to develop, two conditions are essential:

• Sufficient snowfall throughout the year

• Temperatures low enough that the snow does not completely melt during summer

In Iceland, these conditions typically exist above approximately 900–1,200 metres above sea level, depending on the region.

Whether a glacier advances or retreats depends on its mass balance: the difference between the ice gained through snowfall and the ice lost through melting.

Iceland’s Changing Glaciers

It is easy to think of glaciers as permanent. They are anything but. Glaciers flow, crack, melt, grow and retreat. Like rivers, they are dynamic and constantly changing—just on a much slower timescale.

Although today’s retreat is strongly linked to human-driven climate change, Iceland’s glaciers have never been completely static. Throughout history, they have advanced and retreated as the climate changed.

Following the settlement of Iceland in the 9th century, the climate was generally warmer than during the centuries that followed, and the country’s glaciers were considerably smaller.

Around the 14th century, the climate entered a cooler period known as the Little Ice Age. During the next 500 years, Iceland’s glaciers expanded significantly, reaching some of their largest extents in historical times.

Since the end of the Little Ice Age approximately 120 years ago, Iceland’s glaciers have been retreating almost continuously, interrupted only by brief periods of growth. The last notable advances occurred during the 1990s.

Changes can also be observed over much shorter periods. Routes used for glacier hiking may need to change as the surface melts, crevasses open or close, and access points gradually move.

Ice caves are even more temporary. They form, transform and sometimes disappear within a single season. This is why glacier hiking routes and locations visited during ice cave tours must be assessed regularly rather than treated as permanent attractions.

The Impact on Vatnajökull National Park

The effects of climate change in Iceland are especially visible in Vatnajökull National Park, where the landscape is constantly being reshaped by moving and retreating ice.

As outlet glaciers become shorter and thinner, they provide less support to the surrounding mountainsides. This can increase the likelihood of rockfalls and landslides as previously ice-supported slopes become unstable.

Local glacier guides witness many of these changes from season to season. Areas that were once easily accessible may require different approaches, while new crevasses, meltwater channels and ice formations appear elsewhere.

At Local Guide, our glacier hiking routes and ice cave tours are therefore selected according to current conditions. Safety, accessibility and the quality of the experience guide each decision, which means the exact route and natural features visited may change throughout the season.

Glacier retreat can create landscapes of extraordinary beauty, but that beauty often carries a more complex environmental story.

As glaciers retreat, meltwater fills some of the valleys left behind, creating glacier lagoons scattered with floating icebergs.

The most famous is Jökulsárlón, where bright blue icebergs drift towards the Atlantic Ocean while seals can sometimes be seen swimming between them. It is one of Iceland’s most photographed locations—and for good reason.

Yet Jökulsárlón has not always been here. Just over a century ago, the lagoon did not exist.

It began to form as Breiðamerkurjökull, one of Vatnajökull’s largest outlet glaciers, retreated during the first half of the 20th century. The lagoon continues to grow as the glacier retreats further inland.

Jökulsárlón is therefore both an extraordinary natural attraction and one of the clearest visible consequences of the retreat of Breiðamerkurjökull.

Beyond the Ice: Wider Consequences

The retreat of Iceland’s glaciers does not only affect the scenery. It also changes the way Iceland itself behaves.

As massive ice caps lose volume, the tremendous weight pressing down on the Earth’s crust is reduced. This allows the land beneath to slowly rebound, rising by as much as four centimetres per year in some parts of Iceland.

This uplift is already affecting coastal communities such as Höfn in southeast Iceland, where changes to the height of the land in relation to the sea create new challenges for harbours and infrastructure.

Scientists are also studying the possible connection between glacier loss and volcanic activity. As the weight of the ice decreases, pressure on underground magma systems may also change. Over long periods, this could influence volcanic activity beneath and around Iceland’s ice caps.

The consequences of glacier retreat therefore extend far beyond the ice itself, affecting Iceland’s geology, ecosystems, waterways and local communities.

Looking Ahead

These changes are already happening, but scientists are also looking decades into the future to understand what may lie ahead.

Climate models suggest that Vatnajökull could lose approximately 25% of its current ice volume over the next 50 years. Looking further ahead, projections indicate that within the next 200 years, only small ice caps may remain on Iceland’s highest mountains.

If Vatnajökull were to melt completely, it would contribute approximately one centimetre to global sea-level rise. While that may sound small, Vatnajökull is only one glacier among many worldwide. Its potential contribution highlights the cumulative impact of glacier loss across the planet.

Exactly how quickly these changes happen will depend partly on future greenhouse gas emissions and the steps taken worldwide to limit further warming.

Why Climate Change in Iceland Matters

The glaciers of Iceland are more than spectacular natural attractions. They are powerful indicators of our changing climate.

Their retreat tells a story that extends far beyond Iceland’s borders, connecting changes around Vatnajökull with the wider challenges facing glaciers, ecosystems and communities around the world.

Understanding the relationship between climate change and Iceland’s glaciers helps us appreciate both the scale of these changes and the importance of reducing greenhouse gas emissions. Every retreating glacier reminds us that climate change is not a distant possibility—it is already transforming landscapes today.

For many visitors, joining a guided glacier hike or ice cave tour is a once-in-a-lifetime experience. It provides an opportunity not only to see the ice up close, but also to learn how glaciers move, how natural ice features form and why routes and conditions change from year to year.

At Local Guide of Vatnajökull, we have explored these glaciers with visitors since 1991. Our local guides choose each route according to the conditions on the day, helping guests experience this remarkable environment safely and responsibly.

The glacier you walk on and see today will not look exactly the same in ten, twenty or fifty years. That makes every visit extraordinary and uniquely connected to a particular moment in the glacier’s history.