Arguably the most important question for humanity in the 21st century is how we will adapt to climate change. While climate change is a multifaceted problem that is going to wreak all kinds of havoc on Earth and its life, humans will inevitably need to focus on preserving resources that are most fundamental to sustaining us. Water is foremost among them. The inorganic compound covers 71 percent of the Earth's surface and is without question one of the most vital resources. Humans cannot survive for more than three days without consuming it, and water is essential to growing and raising the plants and animals that humans rely on for food. Since only three percent of Earth's water is freshwater, and less than half of that is potable (safe for drinking), it would be a very bad thing if climate change made potable water more scarce.
"Climate change is making dry regions drier — and wet regions wetter."
Unfortunately, experts say that is exactly what is happening.
Water is becoming scarce both in quantity and quality, explains East Carolina University associate professor of geology Dr. Alex K. Manda in an email to Salon. Manda added that we can expect "reduction in precipitation amounts due to changing climate, persistent drought conditions [and] excessive withdrawals of groundwater from aquifers." Meanwhile, the quality of freshwater is diminishing, too, owing to "saltwater intrusion [and] pollution of water resources."
Dr. Michael E. Mann can attest to this from his own experience. A professor of Earth and Environmental Science at the University of Pennsylvania, Mann and a team of scientists studied the so-called "water tower" of Asia, the Tibetan Plateau — a natural feature so massive and significant that 2 billion people rely on water from its downstream flow. According to their research, "in a 'business as usual' scenario, where we fail to meaningfully curtail fossil fuel burning in the decades ahead, we can expect a substantial — that is, nearly 100% loss — of water availability to downstream regions of the Tibetan Plateau," as Mann explained in the report. This will imperil the water supplies for "central Asia, Afghanistan, Northern India, Kashmir and Pakistan by the middle of the century."
Nor will the issues be limited to potability.
"One thing we know is that stronger hurricanes and more severe flooding events can wreak havoc on factories and refineries, releasing hazardous chemicals into the environment, as we've seen in Houston, Louisiana, and Alabama," Mann told Salon by email.
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Dr. Ali S. Akanda, an associate professor and graduate director of civil and environmental engineering at the University of Rhode Island, spoke to Salon by email about a different dimension of the climate change/water problem — one of extremes getting more extremes.
Humans rely on irrigated agriculture so heavily that it accounts for roughly 90 percent of our species' total water consumption.
"In short, climate change is making dry regions drier — and wet regions wetter," Akanda says. As such, "the water scarcity problems are getting worse ... we are seeing longer and warmer drought cycles, and over larger geographic areas." He mentioned that urban development is exacerbating water scarcity issues that are already being worsened by warming temperatures (Phoenix, for instance, may in the near future be close to uninhabitable). "Human practices are also playing a major role as urbanization is intensifying the demand in many arid regions where water is already scarce (Dubai, Los Angeles, etc.) and also due to civil unrest and conflicts which are destroying the infrastructure and limiting supplies (Yemen, Ethiopia, etc)."
Humans rely on irrigated agriculture so heavily that it accounts for roughly 90 percent of our species' total water consumption, and is responsible for 40 percent of our total food consumption. Despite that, we are just beginning to figure out ways to meet the biggest challenges caused by our impending water scarcity crisis. Dr. Lorenzo Rosa, the Principal Investigator at Carnegie Institution for Science at the Department of Global Ecology at Stanford University, specializes in this problem and referred Salon to his 2022 report for the journal Environmental Research Letters. As Rosa explains, because our population is expanding, humans will need to expand irrigated agriculture to underutilized rainfed croplands in order to meet future global food demand. Yet we've only begun to quantify how to make irrigation sustainable, despite it being "one of the land management practices with the largest environmental and hydroclimatic impacts." Rosa's study detailed the areas where sophisticated policies will be necessary, ranging from global food security and water quality to energy use and water storage infrastructure.
"Agricultural interventions adopted under current climate conditions may be ineffective under future global warming," Rosa writes. "By the end of the century, freshwater limitations could require the reversal of 60 million hectares from irrigated to rainfed. However, climate change is altering rainfall patterns in a way that will exacerbate water-stress over 70 million hectares of currently rainfed croplands, which provide food for 700 million people worldwide." Even worse, climate change will increase the intensity and length of heat waves, so people will be hotter even as crop yields go down.
While humanity's water future is bleak, it is not hopeless. Akanda, for one, had plenty of policy suggestions.
"There are many," Akanda wrote to Salon. "First and foremost, governments need to do a far better job of risk communication — sharing the science, explaining the details and the potential impacts on food, health, and livelihoods to the affected public." Akanda said another focus should be in forecasting, and sharing resources in that realm. "For example, in a big river basin, all the riparian countries should invest together in a basinwide forecasting scheme instead of unilateral developments," he opined.
Akanda also advocated for better disaster management and contingency planning, all of which "goes without saying," but added that "those are all post-event responses. Governments need to be proactive and preemptive ... armed with early warning systems and efficient plans for adaptation and protection."
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