World Water Day 2025

World Water Day, celebrated on 22 March every year since 1993, is an annual United Nations (UN) observance day held on that highlights the importance of fresh water. A core focus of World Water Day is to support the achievement of Sustainable Development Goal 6: water and sanitation for all by 2030. The day is used to advocate for the sustainable management of freshwater resources and to inspire and educate people around the world to learn more about water related issues and to drive towards conservation. The theme of World Water Day 2025 is ‘Glacier Preservation’.

Key messages for World Water Day 2025

• Glaciers are melting faster than ever. As the planet gets hotter due to climate change, our frozen world is shrinking, making the water cycle more unpredictable and extreme.
• Glacial retreat threatens devastation. For billions of people, meltwater flows are changing, causing floods, droughts, landslides and sea level rise, and damaging ecosystems.
• Glacier preservation is a survival strategy. We must work together to reduce greenhouse gas emissions and manage meltwater more sustainably for people and the planet.

What is the difference between sea ice and glaciers?

Sea ice forms and melts strictly in the ocean whereas glaciers are formed on land. When glaciers melt, because that water is stored on land, the runoff significantly increases the amount of water in the ocean, contributing to global sea level rise. Depleting sea ice triggers other devastating consequences—from depleting available ice on which walrus and polar bears can hunt to changing weather systems around the world by changing ocean currents.

Today, about 10% of land area on Earth is covered with glacial ice. Almost 90% is in Antarctica, while the remaining 10% is in the Greenland ice cap. Antarctica is a landmass surrounded by ocean, and the Arctic is an ocean surrounded by landmasses. The Antarctic Ice Sheet is bigger and thicker than the ice in the Arctic. Antarctica is covered by an enormous, permanent ice sheet twice the size of Australia. The Antarctic Ice Sheet is thousands of metres thick. This glacier ice, which originally fell as snow and hardened into ice over millennia, has an average depth of 2,160 metres and is up to 4,776 metres thick in places.

Impacts of Glacier Melts

• Rising Sea Levels:
  As glaciers and ice sheets melt, the water flows into the oceans, contributing to a rise in sea levels, which can lead to coastal erosion and flooding. This has far-reaching consequences like human displacement, property damage and damage to coastal ecosystems includes wetlands and mangroves.
• Ecological Disruption:
  Melting glaciers can disrupt ecosystems, including the loss of habitat for polar species.
• Extreme Weather Events:
  Melting glaciers can disrupt ocean currents, which in turn lead to changes in temperature and precipitation patterns all over the world. When sea ice is declining, temperature increases, causing a cyclic chain of temperature increase. Melting Arctic ice weakens the polar jet stream, causing more extreme weather events, such as harsher winters in North America and Europe and heatwaves elsewhere. Melting glaciers can also lead to the formation of unstable glacier lakes which can cause floods.
• Altered Water Resources:
  Glaciers are a crucial source of fresh water for many regions, and their melting can disrupt water supplies and impact agriculture and ecosystems.

Causes of Glacier Melts

Since the 18th century, many glaciers around the world have been rapidly melting. Human activities are at the root of this phenomenon since the industrial revolution caused an increase in carbon dioxide and other greenhouse gas emissions. This has in turn raised the global temperature and as a result, glaciers are rapidly melting.

• Global Warming:
  The primary driver of glacier melting is the increase in global average temperatures. Due to rapid industrialization and deforestation, greenhouse gases in the atmosphere have increased leading to warmer atmospheric temperatures.

Effects of glacier melting and sea ice loss

What happens in these places has consequences across the entire globe. With cold water from ice melts flow into warmer ocean, ocean currents will continue to disrupt weather patterns worldwide. Fisheries will get affected due to disruption of aquatic ecosystems due to these newer elements. Coastal erosion will result in loss of landmass and will affect communities and their livelihoods. Weather patterns changes will result in heatwaves and more frequent floods and storms.

In the Arctic, as sea ice melts, wildlife like walrus are losing their home and polar bears are losing their hunting habitats. As glaciers runoff to sea, world’s freshwater resources will be further depleted as well. To mitigate global warming and save the glaciers, global net human-caused carbon dioxide (CO2) emissions must be reduced by 45% from 2010 levels by 2030, reaching net zero around 2050. "Net zero" means balancing greenhouse gas emissions with removals from the atmosphere, stopping global warming.