Water is vital to climate and nature protection. Will it last?

By Mariana Mazzucato, Ngozi Okonjo-Iweala, and Johan Rockström, Co-Chairs of the Global Commission on the Economics of Water.

The climate crisis is at a critical juncture, and there is a missing piece in the debate that requires urgent attention: Water.

Often overlooked in climate discussions, it in fact is indispensable to achieving the Paris Agreement goal of keeping global temperature rise to less than 1.5 degrees Celsius above pre-industrial levels.

Failure to act on water-related issues imperils our ability to make progress on reducing emissions. And adapting to climate impacts is largely about managing water-related extremes.

In a year marked by extreme events from China to India to Libya that show the worrying new trend of “once-in-a-century” or “unprecedented” floods and droughts becoming the norm, it is evident that the water cycle is spinning out of balance.

Every 1 degree Celsius of global mean temperature rise adds about 7% additional moisture to the atmosphere, drying soils, increasing evaporation, supercharging the water cycle and making rainfall more erratic.

To keep 1.5C alive, massive investments in water are needed to guarantee the stability of the global water cycle.

For example, the viability of the planet’s largest carbon stores - wetlands and forests - is closely tied to stable rainfall, but also to the protection of the world’s aquifers, more than half of which are being depleted faster than they can replenish.

In addition, numerous strategies for removing planet-warming carbon dioxide back out of the atmosphere, such as planting forests and burning biomass for energy, with emissions captured, hinge on the availability and responsible management of water.

Any action taken to safeguard the water cycle is, by extension, an action to protect the climate and bolster efforts to hold the 1.5C temperature limit.

The flip side of this is that continued inaction on climate change also intensifies the threat to the water cycle.

Land use change (through e.g. deforestation and wetland depletion) is not only a source of carbon emissions but is also upsetting freshwater availability as much of the planet’s rainfall is generated through moisture from vegetation on land.

A destabilized water cycle will further disrupt rainfall patterns, drive more frequent and more intense water-related disasters, cause material damage and pose growing threats to human and food security.

In short, we need a more holistic approach on the global water crisis.

Firstly, collective action is essential, as no single country, region, or city can tackle the global water crisis in isolation.

Secondly, addressing water challenges requires an economy-wide perspective since all sectors and economic actors rely on water, with agriculture and industries such as textiles contributing significantly to water use and pollution.

Lastly, equity, efficiency, and resilience considerations must be integrated into water solutions, given their relevance to all Sustainable Development Goals (SDGs), including poverty reduction and gender equality.

As co-chairs of the Global Commission on the Economics of Water, we argue that in order to safeguard the water cycle, we must put water at the centre of our economy and our economics, govern the water cycle as a global common good and recognise there is no single policy that will achieve this goal in one stroke.

Solutions must cut across sectors. Mission-oriented economic strategies can mobilize all relevant ministries, sectors, and stakeholders around specific water-related goals, and outcomes-oriented instruments and institutions can help us achieve them. Patient, long-term, and directed finance is also essential to make sure these solutions can succeed.

Economic policies must also be designed with a sharp focus on water conservation and efficiency. It is high time to phase out harmful agricultural subsidies that drive over-extraction and over-use of water. From supporting soy production in the Amazon to palm oil plantations in Southeast Asia, it is time to rethink practices that worsen water scarcity.

In addition, we must recognize trade as a critical lever for action on the water crisis, as it can allow water-stressed nations to import water-intensive crops rather than exacerbate their own water scarcity by growing them locally.

Smart policy mixes can unlock progress not just on water, but also on climate threats.

All the Intergovernmental Panel on Climate Change (IPCC) scenarios that hold to the Paris 1.5C limit assume a major transition in the global food system, from currently emitting some 4 billion tons of CO2 per year to becoming a global carbon sink of some 5 billlion tons of CO2 per year within 30 years.

This is a major undertaking, requiring massive additional biomass to be grown and managed properly in agricultural landscapes. It can be done but will fail without large volumes of freshwater – potentially twice the amount of water used in irrigation globally today.

Furthermore, crucially, focusing more of our attention on water is also critical for efforts to build a more equitable future, as communities underserved by water or otherwise economically challenged will be hardest hit by water extremes caused by climate change.

Water can serve as a connector across sectors and between the global agendas. Collective water action is the key to a just, inclusive and climate-resilient future, where no one is left behind – and the time to get started with building this future is now.

Mariana Mazzucato is a professor in the Economics of Innovation and Public Value at University College London (UCL), Ngozi Okonjo-Iweala is the director-general of the World Trade Organisation (WTO), and Johan Rockström is the director of the Potsdam Institute for Climate Impact Research (PIK). All three authors are Co-Chairs of the Global Commission on the Economics of Water.