One of the biggest impacts of climate change is on water, which in turn affects sustainable development and security. But in contrast to internationally coordinated information about rising temperatures, data on water resources is patchy and incomplete.
This year’s World Water Day and World Meteorological Day are therefore both dedicated to Climate and Water. One of the underlying themes is that we can’t manage what we don’t monitor and measure – a message which has become unfortunately too familiar in the ongoing COVID19 pandemic.
World Meteorological Day showcases the essential contribution of National Meteorological and Hydrological Services to the safety and well-being of society. This work continues 24/7 despite the challenges and constraints of the pandemic.
In a message, UN Secretary-General António Guterres said that the hydrological cycle is often taken for granted. “But it lies at the heart of many of our global Sustainable Development Goals — from ending hunger, to ensuring health and well-being, enabling productive industries, sustaining thriving communities and unlocking the potential of affordable and clean energy for all.”
“We need to manage climate and water in a more coordinated and sustainable manner to address the urgent need for improved forecasting, monitoring and management of water supplies and to tackle the problem of too much, too little or too polluted water. We cannot manage what we do not measure. Improved hydrological monitoring and forecasting are vital to underpin effective water management policies and flood and drought early warning services,” he said.
Every drop counts
Water is life. On average, a human being cannot survive more than three days without water. Amid the COVID-19 pandemic, an estimated 3 billion people worldwide lack basic handwashing facilities.
Over two billion people live in countries experiencing high water stress, while around four billion people face severe water scarcity for at least one month every year. By 2050, the world’s demand for fresh water will be 20 to 30% higher than it is today.
Most rivers and freshwater bodies are transboundary, and decisions by one country on water resource management often have implications for other countries, thus making water a potential source of both peace and conflict.
Climate change and water
Climate change is impacting snow cover and the “water towers of the world” – the snow and ice on mountains that feed fresh water supplies. Key glaciers have been melting for more than three decades, according to international monitors, leading to an increase in short-term hazards like landslides and avalanches and a long-term decrease in water security for future generations.
A much greater proportion of annual precipitation is now falling in extreme precipitation events rather than spread more evenly throughout the year, increasing the risk of flash floods, one of the deadliest natural hazards.
In many parts of the world, seasonal rainfall patterns are becoming more erratic, affecting agriculture and food security and the livelihoods of millions of people.
The multi-agency Statement on the State of the Global Climate 2019, coordinated by WMO, said that after a decade of steady decline, hunger is on the rise again – over 820 million people suffered from hunger in 2018.
The food security situation deteriorated markedly in 2019 in some countries of the Greater Horn of Africa due to climate extremes, displacement, conflict and violence. Exceptional dryness in March and April was followed by unusually heavy rainfall and floods in October-December, contributing to the worst desert locust outbreak in decades.
According to the climate statement, more than 6.7 million new internal disaster displacements were recorded between January and June 2019, triggered by floods and tropical cyclones in Southeast Africa, South Asia and the Caribbean. This number was forecast to reach close to 22 million in 2019, up from 17.2 million in 2018. Of all natural hazards, floods and storms contributed most to displacement.
Count every drop
Climate and water data underpin the management of surface-water supplies and disaster risk reduction. These include calculations of the frequency and duration of heavy rainfall, the probable maximum precipitation and flood forecasting.
And yet, at a time when it is needed more than ever before, the capacity to forecast, monitor and manage water is fragmented and inadequate.
Climate and water both lie at the heart of the Sustainable Development Goals – the package of 17 crosscutting themes adopted by the international community in 2015. With just 10 years remaining until the 2030 target for achieving the goals, WMO is stepping up its efforts.