World Water Day has been marked annually on March 22 since 1993. It is an annual UN observance focusing on freshwater, primarily to support the sixth Sustainable Development Goal: Water and sanitation for all by 2030. Every year, the UN releases the World Water Development Report, and for more than 10 years, the report has covered different thematics. This year’s report is on mountains and glaciers. According to the UN’s current report, mountains and glaciers supply half the annual freshwater flows - around 55 to 60 per cent - and two-thirds of irrigated agriculture may depend on mountain waters. Additionally, mountains and highlands reduce the risk of erosion and landslides, cool local temperatures and produce high-value products such as medicinal plants. However, due to climate change and rapidly rising global temperatures, many of these benefits are at risk. According to the World Glacier Monitoring Service, the world has been losing tonnes of ice mass. Nearly 80 per cent of the greatest losses - "negative mass balances" - have been recorded since 2010. In 2024, the world lost more than 1.2 tonnes per square metre of ice, the highest amount in the past three decades. Since 1950, it has accumulated a mass balance of minus 27.4 tonnes per square metre or the loss of more than 30 metres of glacier-wide ice thickness. The regions more affected are Central Europe and the Southern Andes. Melting glaciers are also responsible for rising tides. By 2023, two-thirds of sea level rises were due to melting glaciers. According to the European Space Agency, between 2000 and 2023, ice loss contributed 18mm to global sea levels. Although the mountains of the Arab region are often overlooked, these areas have an essential role in providing water, in the form of snowmelt, for agriculture, particularly in sustaining crops during the summer when rainfall is limited. It is also responsible for communities and centres of economic activity in tourism and industry. Mount Lebanon (extending nearly the entire length of Lebanon) and the High Atlas Mountains (stretching through Algeria, Morocco, and Tunisia) are the main providers of water in the region. Snowfall accumulates in several mountains over winter. As the weather warms up during the spring, the melting snow feeds into streams, reservoirs and aquifers at lower elevations. Nonetheless, due to climate change, seasonal snowfall and overall precipitation are expected to decrease, affecting snow cover duration, depth, and the availability of freshwater resources. These expected reductions together with projected population growth will lead the Arab region to struggle with water-related issues such as sanitation and hygiene and fall below the absolute water scarcity threshold by 2050. For this reason, scientists in the UAE are working to develop more effective desalination and water treatment in the Gulf. <a href="https://www.thenationalnews.com/opinion/comment/2025/03/21/the-worlds-water-crisis-is-growing-and-scientists-in-the-gulf-are-finding-solutions/" target="_blank"><u>Nidal Hilal</u></a>, a professor of engineering and the director of NYU Abu Dhabi Water Research Centre, works on membrane technology and nanotechnology for water purification. At the Water Research Centre, teams work to improve membrane design to reduce energy and carbon emissions when treating water and heavy metal removal from wastewater, a relevant issue in water-scarce regions. Also, the team has manufactured the first UAE-made membrane for reverse osmosis, focused on water properties in the Arabian Gulf. Considering 70 per cent of water usage goes to agriculture, they use membrane technology to reclaim wastewater for this sector.