By Paul Roberts / For The Herald
Water is a defining characteristic of life. Where there is water, there is life, and without water life as we know it does not exist. Nothing is more fundamental to human wellbeing than access to fresh water. Climate change is altering that essential balance.
The effects of climate change present challenges and stresses to natural water systems, disrupting historically reliable weather and hydrological patterns. The net effect is reducing the supply of fresh water. At the same time, population growth is increasing demand for potable water, irrigation for agriculture and industrial uses.
In 2018 NASA released a study tracking fresh water resources around the globe. The study gathered data to track how fresh water is changing and distinguished shifts in water storage caused by natural variability from trends related to climate change and human impacts. Jay Famiiglietti of NASA’s Jet Propulsion Laboratory in Pasadena, Calif., said: “What we are witnessing is major hydrologic change. We see a distinctive pattern of the wet land areas of the world getting wetter — those are the higher latitudes and the tropics — and the dry areas in between getting dryer. Embedded within the dry areas we see multiple hotspots resulting from groundwater depletion.”
According to the Fifth National Climate Assessment, published in November, human activities are altering the intensity, frequency and duration of many weather and climate patterns. In terms of water, the result can be summarized as: too much, too little, wrong place and wrong time. Warmer air holds more moisture resulting in increased precipitation, flooding and unstable soils contributing to landslides. Hot dry air pulls moisture from the atmosphere, earth and soils including plants and root systems, leaving them more vulnerable to fires, drought, wind and erosion.
Changes to water cycles pose risks to people and nature. Heavy rainfall events are expected to increase and warming increases evaporation. Groundwater supplies are also threatened by overuse. Warming temperatures and drought conditions are expected to increase demand for water in excess of what is necessary to recharge aquifers. Much of America’s farmlands including land in Washington state rely on irrigation water from aquifers.
Water supply corresponds to natural hydrological and geographic systems often defined by their source: rivers, aquifers and lakes. In many instances larger river systems cross political boundaries and rely on complex management agreements allocating scarce water resources. Examples of multi-state agreements include those governing the Columbia, Snake and Colorado rivers. Those agreements are tested as water resources decline, reservoirs dry up and demand exceeds supply.
Nature supplies water to hydrological systems in the form of precipitation: rain, snowmelt and glacier storage and release. These natural systems have evolved over thousands of years under relatively predictable hydrological cycles. As reported in recent climate assessment: “Natural and human systems have evolved under the water cycle’s historical patterns, making rapid adaptation challenging.” Climate change is altering historical precipitation patterns and cycles making them less reliable and predictable. News organizations including The Herald have widely reported diminished snowpack and precipitation this winter.
Water demand is comprised of four main groups competing for limited fresh water resources: potable water for human consumption; irrigation for crops and agricultural uses; industrial uses for manufacturing and processing; and natural resources including habitat and aquifer recharge needs. Some of these water uses, when treated, are potential sources of water re-use such as agricultural drainage and municipal and industrial wastewater.
The University of Washington Climate Impacts Group released a report this month titled: Pacific Northwest Water Year: Impacts Assessment. The report, the fourth of its kind, documents the serious impacts associated with diminishing water resources in Washington, Oregon and Idaho. It finds that in 2023, precipitation was below normal in the northwestern portion of the Pacific Northwest (virtually all of Washington state) and temperatures were above normal. Impacts on water supply, irrigation, natural resources and hydropower generation were affected by high temperatures. “Drought conditions substantially reduced water supply for many drinking water providers, especially those in western Washington.”
The study identifies lessons learned to help water managers adapt to a changing climate. First, seasonal temperature anomalies had a greater effect than precipitation on water supply during two key portions of the water year. Second, monthly and seasonal forecasts are improving, but more can be gained from better sub-seasonal forecasts. Third, seasonal fluctuations in weather require more intensive monitoring of water conditions such as soil moisture and well-water levels.
Climate change is altering our relationship with water, increasing heat, changing weather and precipitation patterns; amount and timing of rain and• snow, and accelerating glacial melting. Responding to these changes will require new ways of looking at water resources and management. Some strategies include:
• Preserving natural systems that support water storage and improve habitat such as wetlands and green infrastructure;
• Recycling and reusing water resources — also known as “One Water” — cutting across traditional utility and water system silos, expanding the menu of treatment and technology solutions to efficiently manage water resources;
• Recognizing the relationship and interdependence of food, energy and water (FEW) to address water, agriculture needs and food supply. Washington State University has done interesting work on FEW issues and the disruptions caused by climate change;
• Rethinking how we design, build and finance water infrastructure. Integrating supply, treatment, stormwater systems, reuse and recycling will become critical as water resources become more scarce. Upgrading today’s infrastructure will require new design and engineering, integrating technology with nature.
Paul Roberts is retired and lives in Everett. His career spans over five decades in infrastructure, economics and environmental policy including advising Washington cities on climate change and past Chair of the Puget Sound Clean Air Agency Board of Directors.
Eco-nomics
“Eco-nomics” is a series of articles exploring issues at the intersection of climate change and economics. Climate change (global warming) is caused by greenhouse gas emissions — carbon dioxide and methane chiefly — generated by human activities, primarily burning fossil fuels and agricultural practices. Global warming poses an existential threat to the planet. Successfully responding to this threat requires urgent actions — clear plans and actionable strategies — to rapidly reduce GHG emissions and adapt to climate-influenced events.
The Eco-nomics series, to be published every other week in The Herald, is focusing on mitigation and adaptation strategies viewed through the twin perspectives of science and economics. Find links to the series thus far at tinyurl.com/HeraldEco-nomics.
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