Water and climate: the great challenge for the future

The rise in global temperatures is just one of the many facets of “climate change”, a term adopted by the scientific community in place of “global warming” for its ability to reflect the complexity of systemic interactions on Earth (IPCC, 2021). The dynamics of the hydrological cycle are crucial to understanding the implications of a planet undergoing warming (Huntington, 2006 and Allan & Soden, 2022). We are facing a new hydrological year, which in Spain begins on October 1 and ends on September 30, a period that requires us to pay close attention to unprecedented disruptions in climate patterns and in the availability of water resources (Pörtner et al., 2022).

The sun, which warms the Earth’s surface and atmosphere, drives the circulation of water from the oceans to the atmosphere, from where it falls back to the land as rain, much of which returns to the oceans, thus forming the water cycle. However, when the atmosphere retains more heat due to the increase in greenhouse gases, the normal rhythm of these life-sustaining cycles is disrupted.

In the Iberian Peninsula, the effects of climate change are evident: rainfall is irregular and scarce, evaporation intensifies, and droughts become more prolonged, increasing water stress in a historically vulnerable region. Seasonal cycles, once well defined, are now unpredictable, complicating the planning and management of water resources.

This situation aligns with what the IPCC describes as an “intensification” of the water cycle, marked by more frequent and severe extreme weather events. Storms are more destructive and droughts more prolonged, posing new and difficult-to-predict climate challenges in various regions of the planet.

Another of the most concerning and often unseen impacts is the rise in sea level, caused by the thermal expansion of the oceans and ice melt, which has led to the salinization of groundwater (Oppenheimer et al., 2019). In addition, floods—becoming increasingly frequent and severe—are affecting urban drainage systems and drinking water supplies, facilitating the spread of pathogens that thrive in warmer environments (WHO, 2020).

A sustainable alternative: regenerative agriculture

In the agricultural sector, climate change is reducing crop productivity and increasing irrigation demand, which in turn intensifies pressure on freshwater resources, of which agriculture already consumes more than 70% globally (FAO, 2017). In this context, regenerative agriculture emerges as a transformative strategy. This approach promotes soil sustainability by maintaining fertility through nature’s own resources, without the use of pesticides or chemical fertilizers and by combining agriculture and livestock farming with grazing animals to fertilize the land.

This approach, which prioritizes soil health, biodiversity, and the restoration of natural water cycles, offers a sustainable alternative to conventional agricultural methods, which often rely on intensive water use and chemical inputs (LaCanne & Lundgren, 2018). Regenerative agriculture can not only reduce the need for irrigation by improving water retention in soils, but also contribute to carbon sequestration, helping to mitigate some of the effects of climate change (Gattinger et al., 2012).

In the field of energy generation, the decline in water levels in hydroelectric reservoirs, due to prolonged droughts, could increase dependence on fossil fuels (van Vliet et al., 2016).

At the same time, droughts and other climate-related disasters are driving migration toward urban areas worldwide, often to cities that lack adequate water infrastructure, increasing the exploitation of illegal and unsustainable water sources (Rigaud et al., 2018).

In summary, the connection between water and climate is undeniable, and each annual hydrological cycle underscores the urgency of addressing this relationship. On a warming planet, effective water management is not only vital but essential for our long-term survival. Climate change is redefining water policy, forcing us to rethink its management in an increasingly unpredictable world. The adoption of practices such as regenerative agriculture becomes an imperative necessity to ensure the sustainability of freshwater resources, which are fundamental to our food systems and survival.