As they go, it seemed like a dry and dreary Earth Day, caught in a raft of stories about falling river levels and drought and other impending weather extremes provoked by a changing climate.
Lots of link and air time was devoted to reports about the latest findings by researchers at the National Center for Atmospheric Research showing that the supplies of fresh water are flowing away from the planet’s thirty populations and toward the sparely peopled polar regions.In the American west, where the drumbeat of drought continues to reverberate, the story shared space with a new advertising pitch by the State of California: “Save Our Water,” and a study by Scripps scientists warning that some of the 27 million people who rely on supplies from the Colorado River are going to face shortages in the years ahead, even without climate change. (That’s Hoover Dam, courtesy of the Bureau of Reclamation, holding back a shrinking Lake Mead.)
Across the Atlantic, the stories came on the heels of a report by Oxfam International that the number of people impacted by extreme weather has doubled in the last 30 years and warning that aid agencies could be overwhelmed by climate-related disasters within the decade.
The new NCAR study is the most comprehensive of its kind — an analysis of 50 years of data and modeling work that measures the flow of 925 rivers that carry 73 percent of the world’s running water. While an earlier, smaller study had suggested streamflow in the world’s rivers might rise with global warming, the new study shows a net loss in freshwater flowing into the world’s oceans.
In the Guardian, Susanne Goldenberg quoted author Aiguo Dai that the NCAR analysis “settles the question regarding long-term trends in global streamflow.” Co-author Kevin Trenberth in her account says hardest hit will be Africa, where rainfall will likely be heavier, causing more floods, but less frequent, prompting more droughts.
For the BBC, Matt McGrath noted the link to climate change, which is altering rainfall patterns, and the warning from the scientists that falling water levels “will have a major impact as the human population grows.”
For the Christian Science Monitor, Peter Spotts ably led with the Scripps study of the Colorado, quoting research Tim Barnett’s description of the river as “the life’s blood of today’s modern Southwest society and economy.” The Scripps researchers estimate that by 2050, it says here, even without climate change, the Bureau of Reclamation will be unable to meet delivery schedules 40 percent of the time. If runoff falls by 20 percent, shortfalls will occur 88 percent of the time.
For the Arizona Republic, Shaun McKinnon noted that the gloomy outlook by the Scripps team foresees Colorado shortages even without climate change. “The result in either case would be tough choices among water agencies about who gets water and who gives it up,” McKinnon writes.
For the AP, Randolph E. Schmid, reporting the rivers story from Washington, quotes the director of the Chesapeake Biological Lab at the University of Maryland that many of the major rivers where streamflows are falling “have large populations and drought-stressed ecosystems.”