Water Crisis: Climate Change and the Water Cycle
As the effects of climate accelerate, so do the stories of drought across the globe. Not just drought, but ‘unprecedented’ drought, ‘mega-drought,’ the type that dries up rivers and reservoirs, that slows streams to a trickle, that empties aquifers and leave farmers staring at a cloudless sky and hoping for rain. We are in the midst of a water crisis.
At a recent Climate Cafe Multifaith, Dr. Olivia Miller, a water scientist and hydrologist with the USGS, joined in to lead a conversation so we could learn more about water. This article includes a video of her presentation, information about climate change and the water crisis, and words of hope.
The tremendous gift of water. A flower replenishes from morning dew turned to water in its petals.
Photo by Tattyan.
Lakes and rivers are running dry. From the Platte River in Nebraska, to the Mississippi, to the Colorado River, to the reservoirs of Oregon—what happened to our water? There are a few things, and Dr. Miller walked us through them, starting with rising levels in of CO2 in the atmosphere and the impact of those rising levels on the planetary water cycle. The water news, frankly, isn’t great. However, while Dr. Olivia talked about the challenges we face, she also spoke to solutions and reasons to be hopeful.
Human activity during the industrial age included pumping, transporting and burning massive amounts of fossil fuels for energy. In the last hundred years, the outcome of this activity caused rising levels of CO2 in the atmosphere, a gas that acts like a blanket or greenhouse, reflecting and trapping heat on the earth. This is our starting place. Dr. Miller likens the rising heat as similar to heating up a kettle of water on the stove. She explains, “what happens when you put a tea pot on a hot stove? You're adding heat to this kettle of water, and it boils. This is basic physics. When you add a lot of heat to Earth's system, you're going to get a reaction, it's going to change. You're changing the system.”
Many have seen this graph which shows the rise of CO2 in our atmosphere since the 1960s. Adding CO2 is like adding a blanket around the earth, trapping heat and heating things up. Levels of CO2 in our atmosphere haven’t been this high for about 4 million years.
Keeling Curve from: NOAA Global Monitoring Laboratory
This heat, every a single degree—even a portion of a degree—impacts the entire climate system, including the water cycle. Right now the rising heat can already be measured at a global average of 1.2°C. It is imperative to keep warming below 1 .5°C (which is 2.7°F) to prevent more worsening effects. While a degree or two seems small, to the climate system it is anything but. “When we're talking about long term average changes of a degree, that is a big deal. That's your whole climate system,” explains Dr. Miller. That higher temperature is “changing everything that is affected by your system.”
Heat, then, is effecting the whole system, including the water system. Dr. Miller explains that prior climate changes over millions of years were big, slow changes, changes of the earth in relationship to the sun, such as the 100,000 year pattern of “orbital cycles,” or the “axis changes” in the tilt of the earth, or even “this kind of funny wobble around the axis on a 23,000 year timescale.” These are the usual drivers of periods of heat or cooling—including ice ages. They are incremental and slow and do effect the oceans and circulation.
Contrary to the slow rhythms of earth’s natural systems, the burning of fossil fuels has been like a sudden burst of energy and heat, with a fast CO2 rise causing chaotic and destructive consequences to the planet. The sudden rise is shifting foundational climate systems away from a system that is perfect as a home for humans and toward something we do not yet know. “We're the Goldilocks planet where we have all of these perfect conditions for us, and all of the other amazing creatures on our planet, to exist,” explains Dr. Miller. “for our modern life, the way that all of our modern systems and our society is, we're used to climate working in a certain way.”
In this video, Dr. Olivia Miller explains how CO2 can impact our climate system and water cycle, leading to droughts, floods, and changes to the climate.
A big part of that ‘certain way’ is water. The climate cycle and the water cycle are intertwined, just as is the relationship between heat and CO2 levels in the atmosphere. Explains Dr. Miller, our atmosphere and our water system are “intimately linked…. You can't separate the two. You can't have a water cycle without the climate system.”
The water cycle is the same one we studied in grade school. The sun shines down on the earth and earth absorbs that heat. The heat warms up the ocean, lakes, and earth. The heat also evaporates water from those same places. Much water is evaporated from the ocean, but also from soil, forest, and plants, as well. The evaporated water becomes vapor in the atmosphere. That vapor is often visible as clouds, and returns to earth as precipitation, rain, sleet, snow, or hail.
The water cycle in its simplicity is how water moves around the planet. It could be viewed as a circle from ocean to air to rain. A balanced water cycle means that water is drawn up into the atmosphere as vapor, then rained back down in the right amounts, recharging aquifers, replenishing lakes and hydrating the soils, plants, forests, and animals. Water can also fall as snow, building up snowpack in mountain ranges and packing onto glaciers. Snowpack is important to the summer months as when it melts, fresh, ice-cold water keeps the streams flowing. Our “goldilocks” planet has had just the right cycle of heat, water vapor and rain to keep the plants, animals, and humans healthy and happy for millions of years. But this is now changing.
At its most basic, the water cycle is about water, air and heat. Heat energy is what causes water to evaporate into vapor. More heat means more evaporation, not just from oceans but from land, drying out forests and the soil. More water in the atmosphere means heavier storms on a thirstier planet.
See an image of the water cycle from the USGS. Image: Milford Sound on New Zealand’s South Island, by Ed Maughan.
What happens to this perfect balance when you add heat? Returning to Dr. Miller’s example, burning fossil fuels means we have put the kettle on the gas stove and turned up the flame. In the kettle, the water starts to boil. But what happens when that kettle is earth?
When we add heat to our water cycle a few things happen. Everything gets warmer overall, including oceans, lakes and streams. The atmosphere also gets warmer, and warm air can hold more water vapor. This can mean there is more water in the air, so that when it rains, it can be a downpour. We see these downpours globally with devastating floods. Adding heat also causes more evaporation, and not just from the ocean but from the soils, farmland crops, and forests, as well, sort of like steam from a kettle. Eventually, the kettle on the stove is going to run dry—bone dry. The extra heat means the earth gets drier because more water is evaporated. This is why soils and farms and forests are so dry.
The dry soils, plants, animals and forests are also thirsty, so when it does rain, they drink up all the water they can. This means there is less water as run off in the reservoir, and less seeping into the groundwater. Unfortunately, the heat and evaporation has also made things thirstier. So at a time when more water is needed than ever—and we are using more water, with more demands on water now—reservoirs are emptier than ever. The water cycle, then, becomes a water crisis cycle of heat, dryness, drought, deluge and flood.
In Oregon’s Rogue River Basin, a rich agricultural area of orchards and wineries, reservoirs today stand almost empty, at 23%, 10%, 6%, 4%, and 2% respectively.
The "teacup" diagram depicts current water levels of seven reservoirs, as well as flow measurements for key stream points in the Rogue Basin. See the US Bureau of Reclamation.
In the American Southwest, as in many other parts of the world, the water cycle is changing because climate is changing. The extra heat in the atmosphere is contributing to drought and deluge, where sometimes there is too little and other times there is too much. In the Southwest, while flooding does occur, the most pressing challenge comes from far too little rather than too much. Snowpack and glaciers are melting. Forests are drying out. Lakes are evaporating down to dry, silty soil. And reservoirs are running dry.
This is where ‘scenarios’ come in. What happens next? To try to figure that out, water scientists like Dr. Miller turn to scenario planning. They take the key factors, and plan around what could happen. In addressing the water crisis, the rising CO2 levels in the atmosphere are a central concern. The higher the levels of CO2 get, the warmer the planet will get, and the worse the crisis will get. A lot of what happens next depends very much on how we humans choose to respond to the problem. Will we stop using fossil fuels? How long will we allow emissions levels to rise?
The heat is a one cause of the trouble, and human action/inaction is another. But also, what happens when there isn’t enough water in lakes, streams, forests and soils is that wildfire increases, food production is imperiled, native plants and species are displaced, or struggle to adapt, and, in the American west, energy production is also at risk because a lot of generation comes from hydropower. Says Dr. Miller, “we have this climate system that's affecting our water system, that is then in turn affecting our energy generation system. So it's this kind of cascade of effects.”
The Glen Canyon Dam in Arizona was built to hold water in Lake Powell, and serves as part of the Colorado River watershed, a critical part of water delivery and hydropower generation for a number of western states. Record low water levels in Lake Powell threaten both water AND power supply for millions of people and millions of acres and farmland due to rising heat and ongoing drought.
Image by Gary Yost.
The thing is, the water cycle is a life cycle. When we cause damage to the water cycle, there are rebounding repercussions around the planet. Dr. Miller explains, “there's this interplay of where humans are and where we use water and how our natural system is responding. There are also ecosystem responses. The species that live in in these areas, they're used to certain amounts of streamflow or water.” Widespread change like we are experiencing is daunting, but also, as Dr. Miller notes, “really kind of any change is hard to adapt to.”
Adaptation, though, is now immediately necessary. Adaptation will be both large and small, but will include really big important things such as food production. Arizona and California have been powerhouses of fruit and veggie production, and that requires water. Plants are also sorted into ‘hardiness zones’ based on tolerance to heat and cold and climate. Dr. Miller explains, “if you plant something out of its zone, that plant is not going to be very happy.” Dr. Miller’s charts show that “historical or current climate or hardiness zones” are changing. “As our climate changes, those zones are going to change.”
So what to do? Yes, adaptation. Yes, stop burning fossil fuels. And also, restoration is an opportunity that brings tremendous promise to improve things for the better. Dr. Miller shared the uptick in innovation and clean technologies being developed and deployed at every level. And she also talked about nature-based solutions that work with ecosystems to restore moisture and help support healthy water cycles.
Dr. Miller shared one particular example of nature based solutions, the reintroduction of beavers. “Beavers build dams that make little ponds that sustain wetlands and help groundwater recharge, help stream water, recharge groundwater aquifers.” Beaver dams are a natural way to ensure water “actually goes underground so it's available in drier periods.” Even reestablishing something as adorable as beavers, however, can still be contentious. Change is hard. The good news is that even human-made beaver ponds can help.
Restoration of natural systems can be a boost for the water cycle. Beavers are being restored to watersheds—and humans are getting in on the act—to build dams in local waterways to recharge groundwater and replenish riparian and other systems.
Image by Svetozar Cenisev
We humans are in a new era, and the water cycle is going to be different. We can meet this time with a determination to learn about our earth and its systems, restore wounded and damaged places, renew our practices and life ways so that we prioritize sustainability, and ensure that as we do so, we are especially looking out for those who will be most vulnerable during this era of change.
Dr. Miller is a scientist with charts and data points that detail the challenges we face. Yet she still has optimism to share. She reminds us that humans have navigated great change before, and can do it again. “You know, we've gone through an energy revolution before. We used to burn trees and whale blubber, and we went through this industrial revolution where we switched our energy resources to fossil fuels, and… it brought us all of these modern comforts.” She acknowledges that the era of energy made a lot of innovation possible, and wonders what could be next. “I wonder what the next energy revolution can look like with more renewable energy. What are the improvements in our lives that that can bring? I find that I get hope from that.”
In this video, Dr. Olivia Miller speaks to what gives her hope.
Links to learn more:
USGS National Climate Change Viewer
What will climate feel like in 60 years?
The Carbon Map: https://www.carbonmap.org/
A story map of Disappearing Glaciers.
From the USGS: How much water do you use at home? and How much water does it take to grow a hamburger?
Climate explained: what the world was like the last time carbon dioxide levels were at 400ppm
For more articles, also news and information, see the Faiths4Future blog page.
Olivia Miller is a Research Hydrologist at the U.S. Geological Survey, Utah Water Science Center. Her work focuses on modeling streams and stream water quality, with a particular interest in how climate change impacts water. She grew up in Portland, Oregon, and now lives in Salt Lake City, Utah. In her spare time, she enjoys spending time outdoors camping, biking, and skiing.
Rev. Richenda Fairhurst is here for the friendship and conversations about climate, community, and connection. She organizes the Climate Cafe Multifaith as a co-leader of Faiths4Future. Find her in real life in Southern Oregon, working as Steward of Climate with the nonprofit Circle Faith Future.