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Water flow in Mediterranean rivers to fall by 34 percent by the end of the century, study predicts

ScienceDaily (March 17, 2016)

The rising global average temperature induced by climate change will cause regions such as the Mediterranean Basin to become drier and more arid, in turn directly affecting the availability of water. A study has revealed that river flows in this zone will decrease in headwaters, on average, by as much as 34% by the year 2100 — a figure that will reach 50% during the autumn months.

2015 was the warmest year on record : the global average temperature was 1 ºC hotter than those recorded during pre-industrial times according to the World Meteorological Organization. In fact, 15 out of the 16 hottest years occurred during the 21st century and this trend will continue into the coming decades. According to experts, we will see a rise in temperatures between 2.7 and 3.5 ºC by the year 2100 if this tendency persists.

In this context, the climate will become increasingly dry and arid in the Mediterranean Basin — an area that is believed to be one of the most vulnerable regions to climate change on our planet. Forecasts also predict a major drop in water availability.

In order to understand how rivers and ecosystems will react, a team of scientists from Catalonia analysed the impacts of increasing aridity on the territory. In the study, published in the ’Hydrological Sciences Journal’, the researchers evaluated the main effects of climate change on three medium-sized basins in Catalonia : the Fluvià, Tordera and Siurana rivers.

The results reveal that river flows will suffer generalised reductions between 2076 and 2100, proving more severe in the headwaters of basins with humid conditions (Fluvià and Tordera), where water flow will fall by approximately 34% on average. While the river flow of the most arid basin (Siurana) will drop by 25% on average, the most drastic climatic scenario for the Fluvià River is a reduced river flow of up to 48%.

Story Source  : Plataforma SINC

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