Menu

Javascript is not activated in your browser. This website needs javascript activated to work properly.
You are here

Human freshwater footprint larger than expected shows new study in Science

Dams and irrigation systems mean that human consumption of water is increasing at a far greater rate than was originally thought, according to a study carried out as part of a research thesis by the researcher Fernando Jaramillo, who is employed at the University of Gothenburg and is also part of BECC. The results are published in Science.
Photo: Fernando Jaramillo and Navarino Environmental Observatory.
Photo: Fernando Jaramillo and Navarino Environmental Observatory.

The study carried out by the researcher Fernando Jaramillo, which is now being published in Science, was part of his thesis at Stockholm University, although the thesis was completed in part during the time he held a post-doctoral position at the University of Gothenburg, where he now also works part-time.

“It is an established fact that dams and irrigation systems serve to regulate water, and the local impact they have on rivers and water ecosystems is well known. However, this study shows us that dams and irrigation systems are also major consumers of water when seen from a global perspective,” says Fernando Jaramillo, who is employed by both Stockholm University and the University of Gothenburg.

The new study shows that dams and irrigation systems consume significantly more fresh water than has previously been thought and, moreover, they have a global impact. An increase in both evaporation and the transpiration of water in plants is accelerating the rate of water loss in the atmosphere and means that there is less water available on land.

“The small things we do on the surface of the Earth can have a huge global impact. In the past of the impact of human activity has been underestimated. This impact has indeed been greater than that we have seen in the form of climate change,” says Fernando Jaramillo.

A hundred years of studying the use of water

Photo: Fernando Jaramillo
Photo: Fernando Jaramillo
Fernando Jaramillo and his research colleagues have studied data from 1901 to 2008 relating to climate, hydrology and water use in a hundred large catchment basins spread throughout the world.

The results have raised the previous estimate of the global human footprint in terms of fresh water consumption by nearly 20 percent. The total increase in the loss caused by humankind of fresh water in the atmosphere is calculated at 4,370 sq m3 per year.

“That is the equivalent of two thirds of the annual river flow of the entire Amazon River, which is in a league of its own as the world’s largest catchment basin,” says co-author Gia Destouni, who is based at Stockholm University.

Nevertheless, it has still not been established how much water this involves at global level.

“We need first to quantify and identify the most important incentives for water consumption and to understand the impact this has, in order that we can address the future challenges relating to climate change that result from greenhouse gas emissions and water availability”.

Article in Science: Jaramillo, F., Destouni, G., 2015. Local flow regulation and irrigation raise global human water consumption and footprint. Science 350, 1248–1251. doi:10.1126/science.aad1010

Text by Carina Eliasson, University of Gothenburg

Latest articles

18/09/2017
Application for BECC Research Funding
Application for BECC Research Funding
13/09/2017
Highlights from ClimBEco
Highlights from ClimBEco
29/06/2017
7 Open BECC research positions summer 2017
7 Open BECC research positions summer 2017
21/06/2017
BECC Theme meetings August-September
BECC Theme meetings August-September
21/06/2017
BECC Call for Research Funding 2018-2020
BECC Call for Research Funding 2018-2020