– WIKIMEDIA – Archivo
SANTA CRUZ DE TENERIFE, 8 Jun. (EUROPA PRESS) –
A study by the University of La Laguna (ULL) has investigated the long-term impact of climate change and human activity on the natural water resources of the Canary Islands.
The findings indicate that water availability is expected to gradually decline throughout the 21st century, driven by a rise in average temperatures, evapotranspiration, and stable or decreasing precipitation levels.
The research, titled ‘Island water stress: analyzing Canary Islands’ hydrological response to climate change’, was published in Environmental Monitoring and Assessment and coordinated by Professor Juan Carlos Santamarta Cerezal, a researcher in the Department of Agricultural and Natural Engineering at the University of La Laguna. It focuses on the climatic water balance, also referred to as potential.
This indicator relies solely on climatic factors and is computed from two variables: precipitation, which contributes water to the land, and evapotranspiration, which removes it.
Thus, it does not include inputs such as desalination, measuring specifically the water that the climate makes available independently, as stated in a note from ULL.
This makes it particularly useful for isolating the effects of climate change on water resources.
The research team adapted the FICLIMA methodology for the Canary Islands to project how the climatic water balance will change.
This technique translates global climate models to a highly detailed local scale, capturing the unique features of a region with complex topography and numerous microclimates.
The analysis provides a resolution of 100 metres, marking the first time such detail has been available for the archipelago. It is based on international climate models from the Sixth Report of the United Nations Intergovernmental Panel on Climate Change (IPCC).
Projections are made for three timeframes: short (2021-2050), medium (2040-2070), and long-term (2071-2100), under various greenhouse gas emission scenarios, ranging from the most optimistic to the most critical.
HIGH WATER DEMAND IN TOURISM AND AGRICULTURE
This climatic pressure is compounded by human activity, particularly population growth and the substantial water demands of tourism and agriculture.
The general trend observed in the projections indicates a decline in the climatic water balance, which becomes more pronounced as the century progresses.
The analysis also highlights that these changes will be significantly affected by altitude, noting that coastal areas of the archipelago already exhibit a null climatic water balance, which will increase water stress across the entire territory.
The western islands currently have the highest availability of water.
However, predictions estimate more pronounced percentage declines, relative to the higher current availability on these islands.
In the case of El Hierro, projections suggest reductions in the climatic water balance of between 50% and 75% by the end of the century, depending on intermediate and critical emission scenarios.
On the other hand, models for Tenerife estimate approximately a 50% reduction, equivalent to a decrease of between 50 and 100 litres per square metre of available water.
Meanwhile, the historically arid islands of Fuerteventura and Lanzarote already start from an extremely low climatic water balance, making them more vulnerable to increasing temperatures and declining precipitation.
GRAN CANARIA: NEAR COMPLETE EXHAUSTION OF RESERVES
For Gran Canaria, projections indicate a near-complete depletion of reserves, currently limited to small mountainous areas in the north and centre.
While each island has its unique characteristics, the overall trend for the archipelago points to a decreasing climatic water balance.
The researchers emphasise that the study provides valuable data for more efficient resource management, particularly in light of the rising competition for water among high-demand sectors such as tourism and agriculture.
Strategies already contributing to alleviate scarcity include seawater desalination, the reuse of wastewater, and improvements in storage and distribution.
Nevertheless, according to the authors, these methods still encounter efficiency and energy consumption challenges.
As a result, the study proposes measures such as enhancing industrial water production by integrating renewable energy to reduce dependence on fossil fuels; implementing efficient irrigation techniques and drought-resistant crops; establishing integrated planning for the tourism sector; encouraging cooperation among islands and regions; and incorporating climate resilience into hydrological planning.
According to this research, adopting adaptive policies and an integrated, sustainable approach to water management will allow the Canary Islands to better cope with future shortages and ensure the long-term viability of both natural ecosystems and human activities.
The results can be accessed through the publicly available SICMA-Canarias platform, which provides a view of local climate change scenarios in the archipelago.
This project has recently been awarded the 2026 Chris Binnie Award for Sustainable Water Management.
