Tag Archives: water

Chicago invests in resilient ecological infrastructure

Leslie Kaufman in the New York Times has a good article, A City Prepares for a Warm Long-Term Forecast, that reviews Chicago’s efforts to improve its ecological infrastructure. The article describes the city’s approach to climate change adaptation:

As a first step, the city wanted to model how global warming might play out locally. …  the scientists said, Chicago would have summers like the Deep South, with as many as 72 days over 90 degrees before the end of the century. For most of the 20th century, the city averaged fewer than 15. By 2070, Chicago could expect 35 percent more precipitation in winter and spring, but 20 percent less in summer and fall. By then, the conditions would have changed enough to make the area’s plant hardiness zone akin to Birmingham, Ala. But what would that mean in real-life consequences?

A private risk assessment firm was hired, and the resulting report read like an urban disaster film minus Godzilla. The city could see heat-related deaths reaching 1,200 a year. The increasing occurrences of freezes and thaws (the root of potholes) would cause billions of dollars’ worth of deterioration to building facades, bridges and roads. Termites, never previously able to withstand Chicago’s winters, would start gorging on wooden frames. Armed with the forecasts, the city prioritized which adaptations would save the most money and would be the most feasible in the light of tight budgets and public skepticism.

… Much of Chicago’s adaptation work is about transforming paved spaces. “Cities are hard spaces that trap water and heat,” said Janet L. Attarian, a director of streetscapes at the city’s Department of Transportation. “Alleys and streets account for 25 percent of groundcover, and closer to 40 percent when parking lots are included.” The city’s 13,000 concrete alleyways were originally built without drainage and are a nightmare every time it rains. Storm water pours off the hard surfaces and routinely floods basements and renders low-lying roads and underpasses unusable.

To make matters worse, many of the pipes that handle storm overflow also handle raw sewage. After a very heavy rain, if overflow pipes become congested, sewage backs up into basements or is released with the rainwater into the Chicago River — … As the region warms, Chicago is expecting more frequent and extreme storms. In the last three years, the city has had two intense storms classified as 100-year events.

So the work planned for a six-point intersection on the South Side with flooding and other issues is a prototype. The sidewalk in front of the high school on Cermak Road has been widened to include planting areas that are lower than the street surface. This not only encourages more pedestrian traffic, but also provides shade and landscaping. These will be filled with drought-resistant plants like butterfly weed and spartina grasses that sponge up excess water and help filter pollutants like de-icing salts. In some places, unabsorbed water will seep into storage tanks beneath the streets so it can be used later for watering plants or in new decorative fountains in front of the high school. The bike lanes and parking spaces being added along the street are covered with permeable pavers, a weave of pavement that allows 80 percent of rainwater to filter through it to the ground below. Already 150 alleyways have been remade in this way.

… Awareness of climate change has filled Chicago city planners with deep concern for the trees. Not only are they beautiful, said Ms. Malec-McKenna, herself trained as a horticulturalist, but their shade also provides immediate relief to urban heat islands. Trees improve air quality by absorbing carbon dioxide, and their leaves can keep 20 percent of an average rain from hitting the pavement. Chicago spends over $10 million a year planting roughly 2,200 trees. From 1991 to 2008, the city added so many that officials estimate tree cover increased to 17.6 percent from 11 percent. The goal is to exceed 23 percent this decade.

The problem is that for trees to reach their expected lifespan — up to 90 years — they have to be able to endure hotter conditions. Chicago has already changed from one growing zone to another in the last 30 years, and it expects to change several times again by 2070. Knowing this, planners asked experts at the city’s botanical garden and Morton Arboretum to evaluate their planting list. They were told to remove six of the most common tree species. Off came the ash trees that account for 17 percent of Chicago tree cover, or more than any other tree. … So Chicago is turning to swamp white oaks and bald cypress. It is like the rest of adaptation strategy, Ms. Malec-McKenna explains: “A constant ongoing process to make sure we are as resilient as we can be in facing the future.”

On Dot Earth Andrew Revkin follows up with links to his description of Seoul and other cities that have substantially improved their ecological infrastructure.

More PhD positions in Stockholm

There are three new PhD positions in hydrology at the Department of Physical Geography and Quaternary Geology, Stockholm University, pertaining to the following projects:

  1. Nutrient sources, retention-attenuation and transport in hydrological catchments under climate change (Ref# 463-39-10)
  2. The role of permafrost, hydrological and ecosystem shifts for arctic hydro-climatic interactions and carbon fluxes (Ref# 463-40-10)
  3. Determining and mapping spatial distributions and thawing rates of inland permafrost under climatic change in the arctic/sub-arctic (Ref# 463-41-10)

Click on the links for the complete announcements.  Deadlines for applications are May 23rd.

Resilience Theory in Colombia


Does resilience thinking have any impact at all on the ground? These two very interesting examples came in via Lorena Franco Vidal at the NGO Fundación Humedales de Colombia. In January of this year, the mentioned NGO decided to initiate a climate vulnerability and resilience assessment of the Fúquene wetland complex in the east of the Colombian Andes (2,600 meters over the sea level).

According to Lorena, this work has been very much inspired by a range of publications on “the problem of fit” – that is when the dynamics of complex social-ecological systems isn’t matched by institutions and governance [e.g. Cummings et al 2006, Galaz et al 2008], as well as the Resilience Alliance workbook for scientists. In addition, the evaluation of biochemichal variables (in bottom and water sediments of the lake) are – inspired by Elinor Ostrom’s work – done by the fishermen community of the wetland. According to Lorena, this group of local stakeholders have been training monitoring for 2 years to be able to follow environmental change in the lake system.

But there is more. During 2008 and 2009, papers on “the problem of fit” as well as David Salt’s and Brian Walker’s book “Resilience Thinking”, inspired a suggested reframing of Colombian biodiversity policy towards an increased emphasis on social-ecological systems, and the need to address multilevel interactions in governance. Results of the suggested modification include, amongst other things: i) a new conceptual framework for biodiversity management, based upon the resilience thinking paradigm applied to socio-ecological systems; ii) a model that accounts for the various stability domains in which natural and social systems appear in the territory; and iii) a revision of the state – pressure – response model, in order to include new drivers of change affecting biodiversity.

The outcomes of this latter “update”, are now being used for systematic country-side consultations, and we look forward to hear more from both these initiatives!

Reconnecting floodplains to rivers to reduce systemic flood risk

In policy forum Sustainable Floodplains Through Large-Scale Reconnection to Rivers (Science DOI: 10.1126/science.1178256) by Jeffrey Opperman and others argue that managing flood plains to permit flooding can be a better choice than trying to prevent flooding.  Such a strategy switches from trying to prevent disturbances to managing disturbances.  They write that:

Flooding is the most damaging natural disaster worldwide, and the flood-vulnerable population is expected to grow in coming decades (1). Flood risks will likely increase because of both climate change (1) and shifting land uses, such as filling of wetlands and expansion of impervious surfaces, that lead to more rapid precipitation runoff into rivers. …

Flood-control infrastructure (e.g., levees) prevents high flows from entering floodplains, thus diminishing both natural floodstorage capacity and the processes that sustain healthy riverside forests and wetlands. As a result, floodplains are among the planet’s most threatened ecosystems, even though functioning floodplains—those connected to rivers—are among the most valuable ecosystems for supporting biodiversity and providing goods and services to society (6, 7). We propose that a large-scale shift in land use and policy is urgently needed to achieve economically and environmentally sustainable floodplain management. The area of floodplains allowed to perform the natural function of storing and conveying floodwaters must be expanded by strategically removing levees or setting them back from the river.

Floodplain reconnection will accomplish three primary objectives: flood-risk reduction, an increase in floodplain goods and services, and resiliency to potential climate-change impacts. Efforts should focus on strategic reconnection of large areas of floodplain currently used for agriculture, as large-scale reconnection of densely populated floodplains would be considerably more expensive. The changes we propose will confront considerable socioeconomic and political challenges, but we believe these can be overcome by promoting floodplain land uses that are consistent with private ownership and a vibrant agricultural economy. Although our specific recommendations are for the United States, this vision is applicable worldwide. Similar calls for change have been made in several countries [e.g., (8)].

Reduced Risk, Enhanced Benefit

Large-scale floodplain reconnection will reduce flood risk in two ways. First, land use within reconnected floodplains will move toward activities compatible with periodic inundation. Flood-tolerant land uses (described below) will be much less vulnerable to flood damages and therefore less likely to require disaster relief payments. Second, reconnection increases the area available to store and convey floodwaters and can reduce flood risk for nearby areas. In most of the United States, this benefit occurs haphazardly through levee failure. For example, during 2008 floods in the U.S. Midwest, a town was spared because a nearby levee protecting croplands failed, allowing floodwaters to inundate fields and alleviating pressure on the town’s levees (9). But strategic reconnection of floodplains, designed and implemented to maximize public-safety benefits, holds great promise for reducing local and regional flood risk (8). For example, a study of the Illinois River found that reconnection of 8000 hectares (ha) of floodplain would improve protection for 26,000 ha of farmland by halving the probability of inundation from major floods (10).

Large-scale reconnection of floodplains may also increase flexibility and resilience of water-management infrastructure. Globally, thousands of large, multipurpose dams provide (or are being built to provide) flood control and water supply and/or hydropower. The need for partially empty reservoirs (to store floodwaters) must be balanced with the benefits from full reservoirs (water supply, hydropower, recreation, and environmental flows to maintain healthy ecosystems). Climate-change models suggest that many regions of the world will experience increased frequency of both floods and droughts, exacerbating the challenge of balancing these multiple objectives (1). Large-scale floodplain reconnection provides floodwater storage and conveyance, reducing the need for upstream reservoirs to remain partially empty and thus increasing the benefits they could provide when full. Increased resiliency of water management systems through floodplain reconnection is a promising example of ecosystem-based adaptation to climate change.

The author’s propose that there approach is demonstrated by the Yolo Bypass in California.

Demonstrating Success: The Yolo Bypass
Flooded Yolo Bypass

Flooded Yolo Bypass

Although to date rarely implemented, this vision of large-scale floodplain reconnection is not unprecedented. California’s Yolo Bypass conveys 80% of Sacramento River floodwaters during large events, routing water away from the city of Sacramento (see figure, page 1487 ) (18). The bypass was created in the 1930s by reconnecting a 24,000-ha floodplain when it became apparent that a “levees only” approach would not sufficiently reduce flood damages (19). By conveying large volumes of floodwaters, the bypass increases the flexibility of California’s water management infrastructure. During a March 1986 flood, the bypass conveyed ~12.5 billion cubic meters (bcm) of water, more than three times the total flood-control storage volume in all Sacramento basin reservoirs (3.5 bcm). This occurred during a period when the flood-control system was operating near maximum capacity (20). Without the bypass floodplain, California would need to build massive additional flood-control infrastructure or allocate more of its already strained water-supply storage capacity to flood control.

Two-thirds of the bypass is privately owned, productive agriculture. During inundation, the bypass provides habitat for birds and native fish (18). The bypass provides additional ecosystem services, such as open space for a rapidly growing region, recreation (including revenue-producing duck-hunting clubs), and groundwater recharge (of great value as a water bank during droughts) (14).

Hydrological impact of biofuels

R. Dominguez-Faus and others analyze the impact of different biofuels on water in the USA in their article in Envir. Science and Technology, The Water Footprint of Biofuels: A Drink or Drive Issue? (doi:10.1021/es802162x).  The figure below, from the paper, shows the substantial ecological requirements (and variation) among biofuels.

Figure 1. Evapotranspiration, irrigation, and land requirements to produce 1 L of ethanol (Le) in the U.S. from different crops.

Figure 1. Evapotranspiration, irrigation, and land requirements to produce 1 L of ethanol (Le) in the U.S. from different crops.

They write:

The current and ongoing increase in biofuel production could result in a significant increase in demand for water to irrigate fuel crops, which could worsen local and regional water shortages. A substantial increase in water pollution by fertilizers and pesticides is also likely, with the potential to exacerbate eutrophication and hypoxia in inland waters and coastal areas including Chesapeake Bay and the Gulf of Mexico. This in turn would cause undue financial hardship on the fishing industry as well as negative impacts to these vital, biodiversity-rich, ecosystems. Such threats to water availability and water quality on local and national scales represent a major obstacle to sustainable biofuel production and will require careful assessment of crop selection and management options. It is important to recognize that certain crops such as switchgrass and other lignocelluosic options deliver more potential biofuel energy with lower requirements for agricultural land, agrichemicals, and water.

Climatic factors such as frequency of droughts and floods are beyond human control, but as the wide range of estimated nutrients discharged to surface waters shows, clearly some important variables are within our control. These include crop selection, tillage methods, and location. As more biofuel production is integrated into the agriculture sector it will be important to adopt land-use practices that efficiently utilize nutrients and minimize erosion, such as co-cropping winter grains and summer biomass crops. These land use choices should also focus on establishing riparian buffers and filter strips to serve a dual purpose in erosion control and biomass production. Similarly, a CRP-like program should be considered to promote cellulosic biofuel crop planting in marginal lands to prevent excess erosion and runoff while allowing producers to benefit from historically high commodity prices. CRP-like payments would then help to balance societal goals with ecological benefits and provide financial viability for the farmers making the land use choices. Finally, increasing charges for irrigation water for biofuel crops to market rates should be considered to promote fuel crop agriculture in areas where rainfall can supply the majority of the water requirements and to reflect the true value of water resources in the price of biofuels. Policies and programs should be coordinated to avoid the current situation where some efforts (ethanol subsidies, mandates) bid against other programs (CRP) though both are funded by taxpayers with the common goal of environmental protection.

A Novel for the Long Now

Imagine that we wanted our descendants to persist for 10,000 years. How could we help that to happen? This question motivates most of the research on resilience, as well as initiatives such as Clock of the Long Now < http://www.longnow.org/> and policy-oriented initiatives such as the Millennium Ecosystem Assessment <http://www.MAweb.org>. Many insights about resilience have come from research on native cultures, such as an influential volume by Berkes, Colding and Folke on Navigating Social-Ecological Systems, and many other works cited in this blog and in the journal Ecology and Society.

In Girl With Skirt of Stars, Jennifer Kitchell draws a sharp contrast between modern society and a culture that has occupied the southwest of North America for thousands of years.

Lilli Chischilly is a Navajo lawyer with a full brief of problems. Someone arranged mutilated carcasses of sibling coyotes on the hood of her battered Dodge pickup truck – no doubt a message, but of what?. Her old flame has returned to Indian Country, yet somehow he is connected to an inexplicable murder. Then she is assigned to escort a powerful politician through the Grand Canyon for a publicity stunt – obviously a set-up for a hydropower dam in a national landmark that will drown sites sacred to her people. In the shadowy background a mysterious sniper, motivated by a century-old massacre, stalks the politician. This meticulously-crafted debut novel weaves Navajo ethnography, sexual tension, political power, and the beauty of Grand Canyon country into a fast-paced story. Kitchell’s voice is confident, reflecting her deep knowledge of Navajo culture and the physical beauty of the Southwestern US.  The novel’s ending foreshadows more stories to come. I’m eager to read them.

At one moment in the novel, Lilli brings the politician into an ancient cave with petrographs that hold the key to a culture that can last for ten millennia. Will it be drowned by the dam? This encounter with deep-time resilience is the key to the novel, and perhaps the key to human persistence through the current environmental crisis.

This novel is fun to read. It evokes questions that are central to resilience thinking. It will appeal to students who are interested in natural history, ancient cultures, and connections of native people to modern life. Once you open it you will read it all the way through.

Drinking bottled water is drinking oil

ScienceNOW reports a new paper by Peter Gleick and Heather Cooley in Environmental Research Letters that compares the energy use of bottled and tapwater:

… From start to finish, bottled water consumes between 1100 and 2000 times more energy on average than does tap water.

Bottled water consumption has skyrocketed over the past several years. In 2007, some 200 billion liters of bottled water were sold worldwide, and Americans took the biggest gulp: 33 billion liters a year, an average of 110 liters per person. That amount has grown 70% since 2001, and bottled water has now surpassed milk and beer in sales. Many environmental groups have been concerned with this surge because they suspected that making and delivering a bottle of water used much more energy than did getting water from the tap. But until now, no one really knew bottled water’s energy price tag.

Environmental scientist Peter Gleick of the Pacific Institute, a nonprofit research organization in Oakland, California, and his colleague Heather Cooley have added up the energy used in each stage of bottled-water production and consumption. Their tally includes how much energy goes into making a plastic bottle; processing the water; labeling, filling, and sealing a bottle; transporting it for sale; and cooling the water prior to consumption.

The two most energy-intensive categories, the researchers reveal in the current issue of Environmental Research Letters, are manufacturing the bottle and transportation. The team estimates that the global demand for bottle production alone uses 50 million barrels of oil a year–that’s 2 1/2 days of U.S. oil consumption. Determining the energy required to transport a bottle isn’t as straightforward. Some bottles of water travel short distances, but others are imported from far-off countries, which increases their energy footprint. Gleick and Cooley found that drinking an imported bottle of water is about two-and-a-half to four times more energy intensive than getting it locally, often outweighing the energy required to make the bottle.

All told, Gleick estimates that U.S. bottled-water consumption in 2007 required an energy input equivalent to 32 million to 54 million barrels of oil. Global energy demand for bottled water is three times that amount. To put that energy use into perspective, Gleick says to imagine that each bottle is up to one-quarter full of oil.

Intensive agriculture’s ecological surprises

regime shift cartoon from TREE paperRhitu Chatterjee has written a news article Intensive agriculture’s ecological surprises in Environ. Sci. Technol. (July 2, 2008) about a paper Agricultural modifications of hydrological flows create ecological surprises (doi:10.1016/j.tree.2007.11.011) that Line Gordon, Elena Bennett and I published in TREE earlier this year.  From the article:

Previous reports have outlined ways that agriculture alters ecosystems by changing hydrology. The new study, led by Line Gordon of the Stockholm Resilience Centre, classifies these changes, or “regime shifts”, from one ecological state to another into three categories: through agriculture’s interaction with aquatic systems, as in the case of nutrient runoff; in the interactions of plants and soil, as in Australia’s salinity issues; or by influencing atmospheric processes such as evaporation and loss of water by plants (transpiration), as in the rapid drying of the Sahel in sub-Saharan Africa.

The authors “make it clear that agricultural practices result in these regime changes by altering water quality and available quantity,” says Deborah Bossio, a water expert at Sri Lanka’s International Water Management Institute.

“The increasing demand for food, feed, and fuel is placing enormous pressure on the world’s arable lands,” says ecologist Simon Donner of the University of British Columbia (Canada). Awareness of agriculture-related environmental problems has been growing in the past few years, says Bossio. But some of that awareness has been lost in the “current frenzy of global food crisis shifting the balance back toward increasing yield.”

Be it the desertification of the Sahel, the dead zone in the Gulf of Mexico, or the increasing salinity in Australia, countries all over the world are already trying to solve some of these problems. But the fixes are not quick, and the results of their efforts are often hard to predict.

Given the difficult-to-repair, or even irreparable, nature of the problems, agricultural systems must be made resilient to change, the authors argue. The new study adds to “the increasing chorus of voices” that emphasizes the need to avoid irreversible ecological damage, says Donner.

However, the science of understanding ecological regime shifts is still young, which makes it difficult to predict when the changes will manifest. “The tipping points aren’t very well understood at all,” says Bossio. Researchers first need to understand the various biophysical factors involved and how those factors interact with one another, the authors say.

For now, ecologists, agronomists, and regulators can acknowledge the problem and encourage certain practices to minimize the likelihood of some of these water-related changes. People should begin by viewing agriculture not simply as a source of food but also as a source of ecosystem services like water and biodiversity, says coauthor Garry Peterson of McGill University (Canada). For example, Australian farmers are adopting mosaic farming, which involves combining annual crops, pastures, and perennial trees into the same landscape. This restores biodiversity and hydrology and prevents the rise of salinity.

“If we don’t heed the management lessons from the past, many of which are listed in the paper, we are bound to face many more ecological surprises in the coming decades,” says Donner.

Climate change amplifies eutrophication

Hans Paerl and Jef Huisman have a perspective article in Science that reviews how climate change may promote blooms of cyanobacteria Blooms Like It Hot (320 (5872): 57 ):

Nutrient overenrichment of waters by urban, agricultural, and industrial development has promoted the growth of cyanobacteria as harmful algal blooms (1, 2). These blooms increase the turbidity of aquatic ecosystems, smothering aquatic plants and thereby suppressing important invertebrate and fish habitats. Die-off of blooms may deplete oxygen, killing fish. Some cyanobacteria produce toxins, which can cause serious and occasionally fatal human liver, digestive, neurological, and skin diseases (1-4). Cyanobacterial blooms thus threaten many aquatic ecosystems, including Lake Victoria in Africa, Lake Erie in North America, Lake Taihu in China, and the Baltic Sea in Europe (3-6). Climate change is a potent catalyst for the further expansion of these blooms.

Rising temperatures favor cyanobacteria in several ways. Cyanobacteria generally grow better at higher temperatures (often above 25°C) than do other phytoplankton species such as diatoms and green algae (7, 8). This gives cyanobacteria a competitive advantage at elevated temperatures (8, 9). Warming of surface waters also strengthens the vertical stratification of lakes, reducing vertical mixing. Furthermore, global warming causes lakes to stratify earlier in spring and destratify later in autumn, which lengthens optimal growth periods. Many cyanobacteria exploit these stratified conditions by forming intracellular gas vesicles, which make the cells buoyant. Buoyant cyanobacteria float upward when mixing is weak and accumulate in dense surface blooms (1, 2, 7) (see the figure). These surface blooms shade underlying nonbuoyant phytoplankton, thus suppressing their opponents through competition for light (8). Cyanobacterial blooms may even locally increase water temperatures through the intense absorption of light. The temperatures of surface blooms in the Baltic Sea and in Lake IJsselmeer, Netherlands, can be at least 1.5°C above those of ambient waters (10, 11). This positive feedback provides additional competitive dominance of buoyant cyanobacteria over nonbuoyant phytoplankton.

Global warming also affects patterns of precipitation and drought. These changes in the hydrological cycle could further enhance cyanobacterial dominance. For example, more intense precipitation will increase surface and groundwater nutrient discharge into water bodies. In the short term, freshwater discharge may prevent blooms by flushing. However, as the discharge subsides and water residence time increases as a result of drought, nutrient loads will be captured, eventually promoting blooms. This scenario takes place when elevated winter-spring rainfall and flushing events are followed by protracted periods of summer drought. This sequence of events has triggered massive algal blooms in aquatic ecosystems serving critical drinking water, fishery, and recreational needs. Attempts to control fluctuations in the discharge of rivers and lakes by means of dams and sluices may increase residence time, further aggravating cyanobacteria-related ecological and human health problems.