Climate change in the Andes is shrouded in myths that risk concealing the real issues
It’s a myth that rising temperatures and the melting of glaciers in the Andes is the main factor influencing water availability.
This finding emerges from an investigation by the Consortium for Sustainable Development of the Andean Ecoregion (CONDESAN), which addresses the myths and truths about the relationship between water resources and climate change in the Andes.
Bert De Bièvre, hydrologist and principal researcher for the study, says that while climate change does influence reduced water supply, it is not the sole cause.
Water shortages in the Andes can also be attribute to increased water demand; the deterioration of watersheds and ecosystems that affect the capacity of regulation and flows in the dry season; as well as natural climate variability.
An uncertainty in the link between climate change and water security is expected rainfall patterns. “We have no idea of how rains might behave in the future. No one can demonstrate that rainfall patterns have changed or will change, and there are no similarities between the predictions made so far,” De Bièvre says.
Another uncertainty is that the volume of water the basins provide is decreasing drastically. This is because our perception of decline is based on the increasing demand for the water resource, the decrease of flow in the dry season, and local degradation.
What is also a certainty is that some ecosystems are now occurring higher in the Andes than they usually do, along with their hydrological properties. This is because the altitudinal limits between ecosystems are determined by average temperatures which are increasing as a result of global warming.
Another certainty is that temperature has and will increase significantly, and in the case of the Andes this increase is much greater. “The temperature will increase more at altitude than at sea level, approximately doubling at 3000 metres.”
“A proper analysis of what we know and what we do not know gives us the basis to design actions and projects efficiently. We must rely on this to make things right and not reinvent the wheel each time,” concludes De Bièvre.
By Alejandra Visscher