Explain why glaciers are melting due to climate change.

Global temperature rise and accelerated melting of glaciers

For over a century, the average temperature on Earth has been rising rapidly, primarily due to human activity. This global increase is causing accelerated melting of glaciers all around the planet. Glaciers melt when they lose more mass through melting than they gain from snowfall. With higher temperatures, the melting season becomes longer each year, and glaciers no longer have the time to regenerate. Several major alpine glaciers have already lost more than half of their volume in a century. In polar regions, annual melting is also skyrocketing: the Greenland ice sheet is now losing billions of tons of ice each year. This rapid melting is directly causing a rise in sea levels worldwide.

Reduction of albedo effect and amplification of glacier melting

Ice acts as a giant mirror by reflecting a significant portion of the solar light received back into space. This is what is called the albedo effect. The problem is that the less ice there is, the more dark ocean or exposed rocks there are. These dark surfaces absorb much more solar radiation, converting that energy into heat and causing local temperatures to rise even further. This creates a sort of vicious circle: the more ice melts, the hotter the planet gets—and the hotter it gets, the faster the ice melts. This phenomenon thus significantly accelerates the loss of ice on our planet, particularly at the poles and in mountain glaciers.

Consequences of ocean warming on marine glaciers

When the oceans warm, it melts the marine glaciers from below: this basal melting weakens their stability, accelerates their detachment, and thins the ice shelves that support them. If these ice shelves lose volume, the entire glacial flow from the continent speeds up, leading to a rapid rise in sea level. Studies show, for example, in Antarctica that warm water can penetrate under the glacial tongues, accelerating their melting and threatening the stability of glaciers previously considered stable. These phenomena create a kind of irreversible domino effect: the more the oceans warm, the more the glaciers weaken and fracture.

Impacts of precipitation and climate changes on glacier balances

Precipitation plays a key role in the balance of glaciers. Normally, the snow that falls at high altitudes feeds these glaciers by making them grow, which is called the glacial balance. However, with climate change, precipitation is increasingly falling as rain, even at high altitudes, rather than as snow. As a result, instead of accumulating to strengthen the glaciers, this water accelerates their melting and reduces their thickness. Various climate changes are also disrupting usual precipitation patterns. Some regions are now experiencing prolonged drought periods, while others face short bursts of intense precipitation. In both cases, this harms the proper development of glaciers and undermines their long-term stability.

Human activities as an aggravating factor of the glacier melting phenomenon.

Our greenhouse gas emissions related to transport, industry, and agriculture intensify glacier melting. The combustion of fossil fuels releases carbon dioxide (CO₂) and methane, two gases that are very effective at trapping heat and thus warming the atmosphere. The result: temperatures rise, ice melts faster, and the entire natural cycle is disrupted. The massive deforestation of forests, true "CO₂ traps," only worsens the problem, as it further reduces our capacity to absorb this gas. Not to mention air pollution, with our soot particles settling directly on the icy surface, making it darker, decreasing its reflective power, and significantly accelerating its disappearance.