To Stop Adding to the Problem, Use Climate Positive Design

Climate Positive Design

Let’s be frank: landscape architecture projects can add to the climate crisis. If projects aren’t purposefully designed and built with their carbon footprint in mind, they may be contributing more greenhouse gas emissions to the atmosphere than they can sequester over their lifespan. Projects can incorporate too much concrete and other carbon-intensive materials, too few trees and shrubs, or require industrially-produced fertilizers or gas-powered mowers or pruners for long-term maintenance, running up long-term emissions.

Instead, landscape architects can design and build projects that are not only meant to be carbon neutral, but go further and become “climate positive,” meaning that over their lifespan they sequester more greenhouse gas emissions than they embody or produce.

To help landscape architects reach this goal, Pamela Conrad, ASLA, a principal at CMG Landscape Architecture in San Francisco, has created an inventive new platform: Climate Positive Design.

She has also thrown down the gauntlet with a new challenge: if all landscape architects and designers use the approach, they could reduce greenhouse gas emissions in the atmosphere by 1 gigaton by 2050. That would put landscape architecture well within the top 80 solutions found in the Project Drawdown report.

Climate Positive Design

According to Conrad, Climate Positive Design “is not only an opportunity to re-imagine how we design our world from every aspect, but a responsibility.”

Using the site’s Pathfinder tool, landscape architects and designers can establish and then ratchet up specific sequestration and emission reduction targets for their own projects. “A target of five years is suggested to offset carbon footprints for greener projects like parks, gardens, campuses, and mixed-use developments. For more urban projects that require a greater amount of hardscape to accommodate programming, twenty years is the targeted offset duration.”

Through her research, which includes illustrative and useful case studies produced with CMG, Conrad found that “targets could be met without changing the program or reducing the quality – the projects merely became greener.”

Case study / Climate Positive Design

The website offers a design toolkit that not only shows landscape architects how to incorporate more trees and shrubs and preserve carbon in soils, but also how to replace carbon-intensive materials used in pathways, walls, fences, and furnishings with low-carbon alternatives. Conrad makes it easy to find sustainable options.

A few details about the process: Landscape architects or designers who log a project in the app are asked to input the sources of carbon, which could include “approximately eighty different types of materials used in landscape projects such as paving, walls, fences etc. and their associated ‘embodied carbon’ from extraction, manufacturing, transportation, installation, use/maintenance and replacement. The data is derived from the Athena Impact Estimator.”

Then designers are asked to add in data about the carbon sinks they are incorporating, which could include: “trees, plants, wetlands and certain types of meadows/lawns capture CO2 from the atmosphere and sink carbon into the soil.” Conrad notes that “all data used for calculating sequestration and decomposition for trees and shrubs is obtained from the U.S. Forest Service.”

Lastly, landscape architects and designers can add in the “carbon costs,” which “represent emissions associated with mowing/pruning performed using machinery and fertilizer use for trees and shrubs. These emissions occur regularly over the lifespan of the project and are often referred to as ‘operational carbon.'”

Once this information is submitted, landscape architects will receive a Climate Positive score that indicates how long it will take to offset the carbon embedded in the project or expended through maintenance operations. The website will then send design recommendations for reducing emissions and increasing sequestration much faster. And each project has a dedicated page that can be re-visited and re-evaluated or shared.

Climate Positive Design

Data collected through the app will be reviewed by advisory partners including
the Landscape Architecture Foundation (LAF), American Society of Landscape Architects (ASLA), Canadian Society of Landscape Architects (CSLA), International Federation of Landscape Architects (IFLA), and the Landscape Architecture Canada Foundation (LACF).

Conrad formulated the system during her Landscape Architecture Foundation (LAF) fellowship. It’s also the result of years of research and collaboration with Atelier Ten.

Go to Climate Positive Design.

Also, check out ASLA’s guide to climate change mitigation and landscape architecture and series of sustainable residential design guides.

ASLA Announces 2019 Professional & Student Awards

ASLA 2019 Professional General Design Award of Excellence. Heritage Flume. Sandwich, MA. Stimson / Ngoc Doan

The American Society of Landscape Architects (ASLA) announced the 2019 Professional and Student Award winners.

Chosen from 544 submissions, this year’s 36 Professional Award winners represent the best of landscape architecture in the General Design, Residential Design, Analysis & Planning, Communications, and Research categories. In addition, a single Landmark Award is presented each year.

A full list of this year’s Professional Award winners can be found at www.asla.org/2019awards

ASLA 2019 Student General Design Award of Excellence. “Y” Shape Jetty System: A Sustainable Solution for Coastal Ecosystem Protection, Population Retreat, and Global Tourism Development, Yi Song, Student ASLA, University of Texas at Austin.

Chosen from 368 submissions, this year’s 26 Student Award winners represent the bright future of the landscape architecture profession in the General Design, Residential Design, Analysis & Planning, Research, Communications, Student Collaboration and Student Community Service categories.

A full list of this year’s Student Award winners can be found at: www.asla.org/2019studentawards

“ASLA’s Professional and Student Awards programs are the oldest and most prestigious in the profession. This extraordinary and diverse array of winners represent both the best of landscape architecture today and the brightest hope for our future,” said ASLA President Shawn T. Kelly, FASLA.

“This year’s awards reflect the global nature of landscape architecture and demonstrate to professionals and the public alike how our profession addresses some of the world’s most pressing problems, including climate change and resilience, livability, and the creation of healthy and equitable environments.”

All Professional and Student Award recipients, their clients, and advisors will be honored at the awards presentation ceremony during the ASLA Conference on Landscape Architecture on Monday, November 18, in San Diego, California. There are still complimentary press passes available.

Background on the ASLA Awards Programs

Each year, the ASLA Professional Awards honor the best in landscape architecture from around the globe. Winners of these prestigious awards are chosen by a jury that represents the breadth of the profession, including private, public, institutional, and academic practice, and exemplify diversity in professional experience, geography, gender, and ethnicity. Submissions are judged blind.

Professional Awards are presented in six categories: General Design, Residential Design, Analysis & Planning, Communications, Research, and the Landmark Award. In each of the first five categories, the Jury may select one Award of Excellence and any number of Honor Awards. It is not guaranteed that an Award of Excellence will be selected each year, as it is up to the jury’s discretion. Only one Landmark Award is presented each year.

This year’s Professional Jury included: Andrea Cochran, FASLA (Chair); Henri Bava; Kofi Boone, ASLA; Gina Ford, FASLA; Deb Guenther, FASLA; John King, Honorary ASLA; Pam Linn, FASLA; John Vinci; and Keith Wagner, FASLA. Joining the Professional Jury for the selection of the Research Category were representatives on behalf of the Landscape Architecture Foundation (LAF) and Council of Educators in Landscape Architecture (CELA): Stephanie A. Rolley, FASLA and Galen Newman, ASLA.

Student Awards are presented in seven categories: General Design, Residential Design, Analysis & Planning, Research, Communications, Student Collaboration and Student Community Service. Like the Professional Awards, the jury may select one Award of Excellence and any number of Honor Awards. It is not guaranteed that an Award of Excellence will be selected each year, as it is up to the jury’s discretion.

This year’s Student Jury included: Linda Jewell, FASLA (Chair); Diana Fernandez, ASLA; David Gouverneur; Robert Gray, ASLA; Damian Holmes; Kendra Hyson, ASLA; Maki Kawaguchi; Signe Nielsen, FASLA; and Daniel Tal, ASLA.

Nature-based Solutions Are Our Best Defense Against Climate Impacts

Climate Ready East Boston / Stoss Landscape Urbanism,

Today in New York City, United Nations Secretary-General António Guterres will convene the 2019 UN Climate Action Summit to, in his words, “hear about how we are going to stop the increase in emissions by 2020, and dramatically reduce emissions to reach net-zero emissions by mid-century.” This Summit comes on the heels of the Youth Climate Strike last week, and kicks off Climate Week in which people in New York and across the country will demand action to mitigate the ongoing climate crisis.

As the world’s leaders gather in New York this week, ASLA calls for all governments convened at the Climate Action Summit to adopt national policies that incentivize investment in nature-based solutions to help communities adapt to the impacts of the climate crisis, with a greater focus on the disproportionate impacts faced by vulnerable and underserved communities.

While it’s encouraging to see international leaders finally thinking seriously about resilience, sustainability and climate change mitigation, I’m extremely proud to say that I belong to an organization and a profession that has been protecting our planet since 1899.

Since our founding, the American Society of Landscape Architects (ASLA) has advocated for nature-based solutions to reduce coastal, inland flooding and the urban heat island effect; improve air and water quality; protect and enhance biodiversity; and support human health and well-being through universal access to nature.

ASLA has always been a vehicle for landscape architects not only to protect and expand our livelihoods, but to advocate for those values we hold as a profession. The Kresge Foundation found ASLA to be one of just nine organizations that have “adopted a holistic approach” to educating their members and the public about climate change “that includes adaptation, mitigation, and the explicit consideration of social justice.”

In 2017, ASLA convened a Blue Ribbon Panel on Climate Change and Resilience that produced a report called Smart Policies for a Changing Climate. The report identifies the following core principles, key planning and design strategies, and public policies that will promote healthy, climate-smart, and resilient communities.

And we didn’t stop there. Just this year, with a grant from the National Endowment for the Arts, ASLA opened our Smart Policies for a Changing Climate Exhibition and website – a demonstration of 20 case studies that show the report’s recommendations at work. From Boston’s multi-billion dollar investment to protect itself from sea level rise and severe storms, to Houston’s Buffalo Bayou Promenade, which is designed to contain greater floodwater, to New Orleans Redevelopment Authority’s community adaptation program, these cases are just a few across the country and around the world that showcase how landscape architects can us nature-based solutions to mitigate the effects of a changing climate.

ASLA 2009 Professional Award of Excellence in General Design, Buffalo Bayou Promenade, SWA Group/Bill Tatham.
Community Adaptation Program in Gentilly, New Orleans, Louisiana / Design Jones, LLC.

ASLA is also a proud signatory of the We Are Still In Declaration. The declaration, signed by 63 cultural institutions and 3,800 leaders representing 15 million Americans and $9 trillion of the U.S. economy, relays our continuing commitment to the goals outlined in the international Paris Climate Agreement and America’s contribution to it.

World leaders are finally coming around to what we at ASLA have long known: nature-based solutions are advantageous to our communities, our environment, and the health of our world. They:

  • Are largely more cost-effective and resilient than engineered “grey” solutions for protecting communities against sea level rise, higher temperatures, and increased flooding.
  • Have many co-benefits like improved community health and well-being.
  • Reduce greenhouse gas emissions to the advantage of our environment.
  • Create well-paying, local green jobs.

When a member joins ASLA, they agree to a code of environmental ethics that states they will make “every effort within our sphere of influence to enhance, respect, and restore the life-sustaining integrity of the landscape for all living things.” This, to me, is the Hippocratic Oath of a landscape architect – one that we live every single day, in every project we take, in everything we do. It is my earnest hope, and the hope of ASLA as an organization, that the leaders gathering in New York today will heed the calls of climate strikers, scientists, and people around the globe to take bold action and protect our planet from the perils of the climate crisis.

Shawn T. Kelly, FASLA, President, American Society of Landscape Architects

Designing a Green New Deal

Environmentally beneficial transmission line easement / LOLA Landscape Architects, .FABRIC and STUDIO 1:1

Close to 1,400 attendees and several thousand online viewers watched the day-long Designing a Green New Deal conference hosted by the University of Pennsylvania, which brought together for the first time the policy experts and activists driving the Green New Deal (GND) with landscape architects, architects, and planners.

“It is really important to think about what it would mean to build out a GND,” said event co-host Billy Fleming, ASLA, Wilks Family Director of the Ian L. McHarg Center. “The policy experts didn’t have anybody that could help them think through what it would look like and how it would work.” Fleming hoped the event would spark a conversation between policy experts and designers about what kind of built work might arise from and hasten a GND, and how those projects could address both climate and social issues.

Some of the most inspiring ideas came during the event’s first session “Beyond Hagiography – Mining the New Deal Legacy.” Nick Pevzner, ASLA, senior lecturer of landscape architecture at the University of Pennsylvania, presented speculative and built projects that put energy infrastructure to creative use and deploy renewable power in sensitive ways (see image at top).

“The GND implies a rapid expansion of renewable energy infrastructure,” Pevzner said. How and where this infrastructure might be situated in the landscape, and what co-benefits it may provide, are issues that landscape architects should be considering.

As Pevzner pointed out, conflicts are already arising between renewable energy infrastructure and existing land use. Landscape design and careful planning can help navigate those conflicts.

Landscape architect Kate Orff, ASLA, founder of SCAPE, who spoke at during the event’s “Bold Visions for a GND” panel, emphasized the ability of design workshops to spark policy. She asked attendees to think about ambitious projects that would transcend municipal and state boundaries, projects that would inspire “new, casual coalitions of self-interest,” and a stronger, greener federal mandate.

Among these ideas were a Mississippi River National Park, as well as a coastal “shore-way” featuring “equitable, managed retreat, investing in living shorelines, and stemming the collapse of coastal biodiversity.”

“We need to visualize and give form to this exciting, new, low-carbon landscape,” Orff said. But is a GND necessary to realize projects of such scope and ambition? Yes, Orff told me. “This kind of change requires federal, state, and local cooperation in ways that are currently elusive.”

Fleming agreed, saying “it’s impossible to imagine a world in which we’re able to take on challenges like climate change, climate justice, and social justice at the scale at which it is occurring without a GND. We’ve reached the limits of what we can do through the project-by-project, private firm-driven development of the world.”

One of the event speakers, Leah Stokes, assistant professor of political science at University of California at Santa Barbara, elaborated on the challenges of de-carbonizing the U.S. power sector with or without a legislative package as transformative as the one the GND implies.

“We’ve been living on borrowed time” in terms of our energy resources, Stokes said. The potential of hydro and nuclear power has for the moment been tapped. Wind and solar represent our best hope at de-carbonizing the power grid and transportation system. In order to do that, the U.S. will have to approximately triple its current capacity in the next 10-20 years, according to Stokes.

In other words, “we have to get really good at building stuff better and quickly,” Fleming said. Beyond projects that foster renewable energy or low-carbon modes of transportation, landscape architects have a role to play in ecological restoration, environmental justice, and social justice. Fleming pointed to the Yellowstone to Yukon Conservation Initiative and the Emscher Landscape Park in Germany as projects that took on critical issues outside of energy, such a biodiversity and adaptive reuse of industrial land.

The Yellowstone to Yukon Conservation Initiative / Y2Y.net
Emscher Landscape Park / Latz+Partners

Architect Peggy Deamer, representing The Architecture Lobby, laid out several principles that designers can hold themselves to that are in line with the GND’s principles. “We have a say in what we build,” Deamer told the audience. “We need to build projects that aren’t just objects of capitalist consumption.” She also emphasized that project stakeholders are not just the owners, developers, or users of a project, but the environmental and social community in which a project sits.

Several other speakers echoed this sentiment, including Orff and Rhiana Gunn-Wright, policy director for New Consensus, who advised the designers in the room to “meet people where they are” in order to listen and share how planning and design can benefit their communities.

Fleming said he expects the conversation between policy experts like Gunn-Wright and design experts to continue, with the McHarg Center facilitating dialogue between greater numbers of design firms and GND policy experts.

Watch the full day-long event:

Adapt Now: New Report Calls for $1.8 Trillion for Climate Adaptation

If global governments invested some $1.8 trillion over the next decade to help communities adapt to climate change, these communities would see some $7.1 trillion in benefits. This is one central finding of Adapt Now, a major new report by the Global Commission on Adaptation, which is led by Ban Ki-moon, Secretary General of the United Nations; Bill Gates, co-chair of the Bill and Melinda Gates Foundation; and Kristalina Georgieva, CEO of the World Bank.

At the report’s launch at the World Bank last week, Axel von Trotsenburg, acting CEO of the World Bank, said gains made in reducing extreme poverty around the world are now being undone by the increased destruction wrought by climate change. More flooding, more hurricanes, longer droughts, more wildfires, and hotter temperatures are hitting the poorest communities hardest. “There are now 100 million people worldwide who are poorer because of climate change.”

Von Trotsenburg estimated that of the billions spent on climate change globally by governments and development agencies, just some 30-40 percent is focused on helping communities adapt to a changing climate; the rest is aimed at mitigation, which is geared towards reducing greenhouse gas emissions. He called for increasing adaptation spending to at least half of all climate change-related investments.

Andrew Steer, CEO of the World Resources Institute, which co-wrote the report with the World Bank, also called for much greater investments to help communities get ahead of the climate impacts they are destined to experience. “We can either plan wisely and smartly now or wait and see much more human misery. We can plan and prosper or delay and have more pain.”

The report calls for spending $1.8 trillion in five critical areas deemed to have the greatest adaption benefit: early warning systems, mangrove protection, climate-resilient infrastructure, improved dryland agriculture, and investments in making water resources more resilient.

According to the report, early warning systems are among the most effective investments. They “save lives and assets worth at least ten times their cost. Just 24 hours warning of a coming storm or heat wave can cut the ensuing damage by 30 percent. Spending $800 million on such systems in developing countries would avoid losses of $3–16 billion per year.”

Protecting and expanding coastal mangroves can also provide a 10:1 return. “Mangrove forests provide more than $80 billion per year in avoided losses from coastal flooding—and protect 18 million people. They also contribute almost as much ($40–50 billion per year) in non-market benefits associated with fisheries, forestry, and recreation. Combined, the benefits from mangrove preservation and restoration are up to 10 times the costs.”

Designing and building climate-resilient infrastructure, such as networks of green infrastructure, can “add about 3 percent to the upfront costs but has benefit-cost ratios of about 4:1. With $60 trillion in projected infrastructure investments between 2020 and 2030, the potential benefits of early adaptation are enormous.” The authors cited The Netherlands’ Room for the River program, which directs river flooding into safer areas using natural and engineered systems, and projects created by landscape architects, such as smart “water plazas,” which have been built in Rotterdam to store excess flood water, as key examples.

Water plaza by De Urbanisten / Rotterdam Resilience Strategy

The report goes into great detail about the need to increase nature-based approaches to both climate adaptation and mitigation, calling for greater investment in creating “sponge cities,” expanding tree canopies, wetlands, and wildlife habitat, and using agroforestry to improve soil moisture and reduce evaporation, all approaches landscape architects have actively promoted for many years. (The sponge city approach, which is now national policy in China, was conceived and promoted by Chinese landscape architect Kongjian Yu, FASLA).

ASLA 2013 Professional General Design Honor Award. A Mother River Recovered: Qian’an Sanlihe Greenway. Turenscape / Kongjian Yu

The report delves into the many co-benefits of natural climate solutions as well, “such as better water quality, more productive natural resources, job creation, improved health, cultural benefits, and biodiversity conservation. Nature-based solutions often work well at a broad scale, such as in whole watershed restorations or along coastlines. They can be more cost-effective than engineered approaches, like seawalls, and can also work well in tandem with those engineering approaches to control floods, protect coasts, and reduce urban heat.”

Perhaps Steer’s most persuasive argument for those focused on the financial bottom line is that investments in resilience are critical to ensuring future growth. Without protective infrastructure that can reduce flood risks and high temperatures and ensure water and food supplies, communities can’t attract the investment needed to grow. Therefore, in the near term, climate risks need to be “made more visible,” not hidden. That is the only way to get governments and the financial sector to increase spending on climate adaptation quickly.

In a panel discussion, Laura Cook, vice president for sustainability at the World Bank, said “good adaptation is good development.” Climate adaptation must become part of the “DNA of every project,” even for things that are seemingly unrelated. For example, climate impacts can have ripple health effects. When flooding hits Kampala, the capital of Uganda, which has population of some 1.6 million, “some 30 percent of the population can’t get to a hospital.” Future health infrastructure investments should then be coordinated with resilient urban planning and design.

Steer was ultimately optimistic, arguing that many countries have shown that we can adapt. In 1970, Cyclone Bhola killed 300,000 people in Bangladesh, and then in 1991, another cyclone killed 138,000 people there. After decades of investment in national and local disaster preparedness and an early warning system, a cyclone that came through the delta country in 2019 resulted in 5 deaths. While even the loss of a few people is horrible, “this is largely a climate adaptation success story.”

Interactive Ooze: Three Visions for a New La Brea Tar Pits

La Brea Tar Pits Mammoths / National History Museum of Los Angeles

Keep the kitschy but beloved fiberglass Columbian Mammoth family or not? That’s just one of many design decisions facing the three teams who are finalists in a competition to re-imagine a museum, active paleontology research center, and public park, which together make up La Brea Tar Pits in Los Angeles.

According to The Los Angeles Times, problems with the current complex include limited entrances and too many fences around Hancock Park, which is itself “circuitous” with “often confusing pathways,” and outdated display exhibitions in the George C. Page Museum, which is decades old and leaks. The complex is also not well connected to the Los Angeles County Museum of Art (LACMA) next door and the Academy Museum of Motion Pictures just down the road.

The National History Museums of Los Angeles County, which runs the site, called for multi-disciplinary teams of architects, landscape architects, artists, and scientists to create bold concepts for an ecological and accessible educational landscape.

They also purposefully asked for dramatically different concepts stakeholders and the public can parse. One proposal calls for totally redesigning the original museum, which is from the late 70s, and two for remodeling and expanding the museum. One proposal calls for removing parking all together, while others call for burying and covering parking spaces in green space. (Previous excavations for a parking garage in the tar pits yielded skeletons of giant ground sloths, dire wolves, a nearly-intact mammoth, and the partial remains of a prehistoric woman).

All the design teams propose integrating building and landscape into a more cohesive whole and creating new circulation systems through the lakes, green spaces, oil pools, and laboratories that can result in a more immersive experience.

The proposal developed by a team led by Danish architecture firm Dorte Mandrop, which includes landscape architecture firm Martha Schwartz Partners, along with Gruen Associates, Arup, and Kontrapunkt, calls for a layered approach that builds off the Pleistocene landscape to create an ecological museum park that is filled with “wonder and sheer fun.”

The museum is currently submerged within landscape berms, with just its “halo” visible, making it difficult to find from some directions. The team proposes gutting the museum, but keeping its essential form, and then lifting it up so it becomes a center point and covering it with a green roof. Pathways from all corners of the triangular site will lead to this more visible educational hub.

La Brea Tar Pits design proposal / Dorte Mandrop, Martha Schwartz Partners, Gruen Associates, Arup, and Kontrapunkt

The landscape itself is completely redesigned. Some “cherished aspects,” like a berm kids love to roll down, will take new form. And the mammoth family will stay. New boardwalks will help visitors explore the new park featuring native-plant lawns and gardens and mega fauna-themed playgrounds. “Discovery scaffolds,” or sculptural fencing, will enable visitors to peer into the gurgling tar pits but also keep these research sites secure. And parking will be buried under expanded green space.

La Brea Tar Pits design proposal / Dorte Mandrop, Martha Schwartz Partners, Gruen Associates, Arup, and Kontrapunkt

Martha Schwartz Partners worked with Pamela Conrad, ASLA, at CMG Landscape Architecture, the founder of Climate Positive Design, to create a landscape design that sequesters an estimated 10,000 metric tons of CO2 through “tiny forests; super-sequestering plants; low-carbon materials like wood, sand, lightweight fill and gravel; and reducing and reusing materials on site.”

La Brea Tar Pits design proposal / Dorte Mandrop, Martha Schwartz Partners, Gruen Associates, Arup, and Kontrapunkt

According to Conrad, “the carbon footprint will be offset within five years of being constructed – meeting the goals of the Climate Positive Design Challenge.”

The second proposal developed by a team led by Diller Scofidio + Renfro, which includes landscape architecture firms Hood Design Studio and Rana Creek Design, along with Nabih Youssef Associates and Arup, embraces the messiness of the oily landscape that seeps asphalt.

The team proposes an entry way into a new museum that will take visitors through the layers of the geological past, sunken plazas where visitors can watch the landscape ooze, an oil creek, and a more seamless tar pit lake.

La Brea Tar Pits design proposal / Diller Scofidio + Renfro, Hood Design Studio, Rana Creek Design, Nabih Youssef Associates, and Arup.

The team also proposes experimentation and exploration in Hancock Park, including different ecological zones and “test landscapes,” as well an interactive dig site where visitors can get closer to the scientific action.

La Brea Tar Pits design proposal / Diller Scofidio + Renfro, Hood Design Studio, Rana Creek Design, Nabih Youssef Associates, and Arup.

But the mammoths are gone, as is parking, which they propose moving off the complex, perhaps to avoid digging an underground parking garage that would disturb the ecological and scientific integrity of the site.

The existing Page Museum would be replaced by a glass cube surrounded by four landscape plates that visitors would be able to walk up (and roll down). The plates are an evolution of the sloped roof lawns DS+R created at Lincoln Center in New York City.

La Brea Tar Pits design proposal / Diller Scofidio + Renfro, Hood Design Studio, Rana Creek Design, Nabih Youssef Associates, and Arup.

Lastly, the concept created by a team led by Weiss/Manfredi Architecture/Landscape/Urbanism, which includes Mark Dion, Dr. Carole Gee, Michael Bierut, Karin Fong, and landscape architects Michael Steiner, ASLA, and Robert Perry, ASLA, proposes generally keeping the form of the existing museum, but expanding the overall exhibition space by adding a second elliptical wing and connecting them via a plaza covered in a berm. The overall effect is a sinuous, interconnected complex that is more open and inviting.

La Brea Tar Pits proposal / Weiss/Manfredi Architecture/Landscape/Urbanism, Mark Dion, Dr. Carole Gee, Michael Bierut, Karin Fong, Michael Steiner, ASLA, and Robert Perry, ASLA

This team is the only one to propose an elevated pathway across the tar lake, creating the opportunity for looping pathways and spaces for vast lawns, “pit stops” for play, intimate “paleobotanical gardens,” and close-up encounters with the fiberglass mammoths. The team proposes planting some 400 trees at the edges of the central greens.

La Brea Tar Pits proposal / Weiss/Manfredi Architecture/Landscape/Urbanism, Mark Dion, Dr. Carole Gee, Michael Bierut, Karin Fong, Michael Steiner, ASLA, and Robert Perry, ASLA
La Brea Tar Pits proposal / Weiss/Manfredi Architecture/Landscape/Urbanism, Mark Dion, Dr. Carole Gee, Michael Bierut, Karin Fong, Michael Steiner, ASLA, and Robert Perry, ASLA

A pathway of discovery leads visitors through the tar pit section of Hancock Park, which would feature Pleistocene-themed native plant gardens and a new amphitheater for public events.

A jury will decide on the winning proposal later this fall.

We Are Designing the Earth, Whether You Like It or Not

“The Monk by the Sea” by Caspar David Friedrich (1808) / Wikimedia

This purpose of this article is to reflect on the Design with Nature Now exhibition that ran over this past summer at the Stuart Weitzman School of Design at the University of Pennsylvania. The exhibition marked the 50th anniversary of Ian McHarg’s 1969 tome Design with Nature and was curated by Fritz Steiner, FASLA, Karen M’Closkey, Billy Fleming, ASLA, Bill Whitaker, ASLA, and myself.

As curators we worked for well over a year to select the 25 works in the exhibition. We began by asking colleagues around the world for project recommendations. We stipulated in some detail that projects had to be “McHargian” in scale and scope. From well over a hundred nominations, we reached the short list of 25 and organized them into five categories: Big Wilds, Urban Futures, Toxic Lands, Fresh Waters and Rising Waters, which can be explored online.

Big Wilds

• Great Green Wall, Africa
• Yellowstone to Yukon Conservation Initiative, USA and Canada
• National Ecological Security Pattern Plan, China
• Malpai Borderlands, Arizona and New Mexico, USA
• Samboja Lestari, East Kalimantan, Indonesia
• Landscape Regeneration of Western Waiheke Island, New Zealand

Urban Futures

• Willamette River Basin Oregon, USA
• Qianhai Water City Shenzhen, China
• Envision Utah Salt Lake City Region, USA
• Medellin, Colombia
• Barcelona Metropolitan Region Plan, Spain

Toxic Lands

• Emscher Landscape Park, Ruhr Valley, Germany
• Stapleton, Denver Colorado, USA
• Freshkills Park, New York, USA
• Queen Elizabeth Olympic Park, London, England

Rising Waters

• The BIG U, New York, USA
• A New Urban Ground New York, New York, USA
• Fingers of High Ground Norfolk, Virginia, USA
• Zandmotor Ter Heijde, The Netherlands
• 2050—An Energetic Odyssey North Sea, The Netherlands

Fresh Waters

• Healthy Port Futures Great Lakes Region, USA
• Room for the River The Netherlands Rijkswaterstaat
• Los Angeles River Master Plan California, USA
• Weishan Wetland Park Jining, China
• GreenPlan Philadelphia Pennsylvania, USA

It’s important to note the final list of projects doesn’t mean we completely endorse the work, nor is the exhibition a collection of the “best of.” This is not an awards forum; it is a representative selection of work that we think does a pretty good job of scoping, extending, and in some cases questioning McHarg’s legacy into the 21st century.

Without being too coy about it, we generally think these projects indicate important directions for the future of the profession. A criticism we accept and have worried over is the collection is geographically and culturally quite limited, itself a reflection of landscape architecture’s current professional reach.

So what do we mean by extending McHarg’s legacy? Simply, the works we’ve chosen tend to be “plannerly,” that is, they are big in terms of site and timescale and tend to involve complex socio-political and ecological processes with multiple authors and agencies. In short, there are no gardens, plazas, or streetscapes (to name but a few types) in this collection. This is not to say these are unimportant, they just don’t fit the raison d’etre, or the occasion of this exhibition.

Turning to the question of designing a planet: the functionalist definition of design is to make a tool that will do something more effectively than prior to the tool’s existence. But what’s most important about this—at least what largely seems to distinguish us to some degree from many other species—is that the invention of the tool, or the desire for the invention of the tool, takes place in our minds before it takes place in the world.

Without wanting to at all elevate humans above other species, we do have an exceptional propensity for imagining causality. In a word, we have foresight.

In Greek mythology foresight was the special gift of Prometheus – the father of humanity. We, the “Anthropos” (meaning not only humans, but also “the lower ones”), received our ability for foresight from Prometheus. Under instruction from Zeus, who wanted some pets to alleviate his boredom, Prometheus made the Anthropos out of clay taken from somewhere between the Tigris and Euphrates, and with the admixture of Athena’s breath, here we are!

As the story goes, Zeus told Prometheus to give the Anthropos some degree of free will so as to make them more entertaining, but he stressed not to give them so much that they might then compete with the Gods themselves. Of course, by giving us not only a modicum of foresight, but also fire, Prometheus gave us everything we needed to do exactly what Zeus feared we would. And the rest, as they say, is history.

Suomi NPP launch by NASA/Bill Ingalls, public domain via NASA.gov

From the origin of the Anthropos we can trace an arc to the 1960s when, just before McHarg released his manifesto, Stewart Brand, the man responsible for persuading NASA to release the original earth image, pronounced: “We are now as Gods and should get good at it.” This is a hugely significant thing to say, but what’s more is that Brand recently updated his statement to “we are as Gods and MUST get good at it.”

In other words, not only have the Gods abandoned us, but we are now so deeply implicated in the workings of the Earth system that we really have no choice but to try and design it. In so far as we know, for the first time in evolutionary history, there is now a form of networked planetary intelligence registering its own environmental predicament. If so, then humanity is the first species in evolutionary history to attempt to design a planet, a fact as preposterous as it is, according to Brand, a necessity.

The poster child for the historical drama in which we now cast ourselves as both the villain and the hero is the atmospheric chemist Paul Crutzen, who popularized the term Anthropocene. As Crutzen explains, the Anthropocene is an act in three parts: first, the industrial revolution; second, the great acceleration (consumer-driven capitalism since 1950); and now he says we should move into a third phase in which we begin to, and I quote, “steward the earth.”

This of course is exactly what McHarg said 50 years ago. Now you might say that we have already designed the planet. Certainly, humanity has colonized and impacted every square inch of the earth’s surface, but we haven’t really done this with foresight. Until recently, we haven’t done it in a way that is self-conscious in regard to the problem of the tragedy of the commons. The question now is not whether we should design the planet, but how. Ironically then: If it’s true that species naturally over consume their environments to their own detriment, then since we have no major predator, we now need to learn to become unnatural. And in a further semantic twist, according to McHarg and his disciples, we can only do this by designing with nature.

However, the problem is this assumes we know what nature is. Truth be told, we do not. Accepting that fact is important because it protects us against anyone ever using nature as justification for authoritarian politics or any number of other oppressive ideas. Accepting then the partiality of knowledge, all we can do is develop approximations of how nature works and try different ways of productively coexisting with it as such.

We write in the introduction to the exhibition’s eponymous book that by asserting the sum-total of what we mean by design (human foresight) could be based on a singular—and in McHarg’s case, a scientific idea of nature—McHarg created a significant intellectual problem for himself and the profession. This problem is brought to light by Ursula Heise during a keynote at the Design with Nature Now conference, which was held at Penn alongside the exhibition in June, 2019.

Heise explains “the basic goal of cultural studies for the last twenty years has been to analyze and in most cases, to dismantle appeals to ‘the natural’ or ‘biological’ by showing their groundedness in cultural practices rather than facts of nature. The thrust of this work, therefore, invariably leads to skepticism about the possibility of returning to nature as such or of the possibility of places defined in terms of their natural characteristics that humans should relate to.”

Design with Nature Now / Lincoln Institute of Land Policy, 2019

Correct though she may well be, the problem with this postmodern skepticism is that if nature is not one thing, it’s everything. And if its everything, its nothing, and if it’s nothing, it can’t very well guide our designs, let alone an entire civilization as McHarg intended.

How then are we to respond to the conditions of ecological crisis? Well, you don’t have to agree with McHarg’s teleology of humanity fitting into a certain idea of nature to accept and use the sheer practicality of his method. Inversely, you also don’t need to be debilitated by the recognition that post-modern nature is a cultural construct. On the contrary, recognizing the design of nature as a cultural construct can be completely consistent with an ecological world view, just not a tyrannical one.

The ecological crisis and the misuse of land that McHarg directly confronted is not just a postmodern cultural construct – it is an appalling reality and McHarg’s importance is that he proposed a simple, replicable, and practical method for addressing it.

McHarg represents then the beginning of modern culture taking responsibility for the land with modern technology. Other societies throughout history have done this in different ways, but a modern method suited to the abstraction of modern development processes had to be created. People like Geddes, Mumford, Leopold, Carson and others provided the narrative and McHarg the method. And that he did this is enough. We don’t need to make him into anything more or less than that.

Designing with Nature Now means designing with the new nature of the Anthropocene. And to understand the Anthropocene we need to turn to both the sciences and the arts. The scientific bible for the landscape of the Anthropocene is, I think, the book Global Change and the Earth System, published in 2005. It is to the Anthropocene what the encyclopedia was to the Enlightenment.

Global Change and the Earth System / Springer

To quote directly from its introduction, the book’s purpose is “to describe and understand the interactive physical, chemical, and biological processes that regulate the total earth system, the unique environment it provides for life, the changes that are occurring in that system and the manner in which these changes are influenced by human actions.” This last expression “…the manner in which these changes are influenced by human actions” is critical because this is not the study of nature as something separate to culture; this is now the study of nature as culture.

Global Change and the Earth System is the work of literally thousands of scientists, all bringing their various models of different phenomena together in an attempt to form a complete, holistic model of the Earth System. The idea being that if we can at least better understand how the Earth system functions then we can make more informed decisions about our actions within that system.

One can imagine the ecological revolution in design, which McHarg catalyzed in regard to settlement patterns and which we are still in the early historical phases of, now means that everything we design will increasingly be conceived, tested, and valued as to how it performs within the larger material flows of the Earth system as a whole. Hyper-McHarg, if you will.

Now, while the scientists are working on their empirical models, the question in the arts is not so much how the Anthropogenic Earth works but what the Anthropogenic Earth means. To wit, just look at the plethora of recent books that use the word Anthropocene in their titles. Notably, almost all are dramatic and apocalyptic. Indeed, thoughout the humanities, there is evidently outright panic about the advent of the Anthropocene. And rightly so, because the old idea of nature as something stable and inviolable, history’s backdrop, has literally just evaporated into the carbon-saturated atmosphere of our own making.

To help make some sense of this panic, I’ve added some keywords to a sample of books on the topic of the Anthropocene (see larger version of the image below). These keywords establish polarizations that demarcate spectrums of current thought, at least as I read it. The first polarization concerns the question of whether or not we should even be calling this the Anthropocene. For its critics, the term naturalizes climate change and casts a new colonizing term over the entirety of the human race, many of whom have had very little to do with the industrial modernity that created the problem in the first place. Instead, they argue this should be called the Capitolocene, which is to say climate change must be apprehended as a cultural matter, and the blame for its advent placed squarely at the feet of first-world capitalism, and presumably communism, since it too has had an appalling environmental record.

Montage of book covers and keywords related to the Anthropocene / Richard Weller

First, with regard to the politics of the environmental movement I would place Eco-socialists at one end of the spectrum and Eco-modernists at the other. For the Eco-socialists, technology (unless its green) is a problem before it is a solution, and it is only through a return to communitarian, small scale, low-population, stable-state economies that true sustainability can be achieved. For the Eco-socialists, only the worst of climate change can now be avoided, whereas for the Eco-modernists, modernity is an incomplete project, and through technological rationality the best is yet to come, or at least, the worst can be avoided.

For Eco-socialists climate change warrants socio-political and theological revolution, something Clive Hamilton, the author of Defiant Earth: The Fate of Humans in the Anthropocene, for example, calls a “rupture” with history. On the other hand, for the Eco-modernists, history since the agricultural revolution is a continuing saga of environmental modification at the hands of technology. In this sense, even though there is now more at stake, for the Eco-modernists we are just doing now what we’ve always done. This latter position is effectively that taken by the other keynote speaker at the Design with Nature Now conference, the geographer Erle Ellis.

Second, to translate this spectrum of environmental thought into design discourse, I use the terms mitigation and adaptation respectively. Taken seriously, mitigation means taking on the causes of climate change, not only the fossil fuel industry, but also the economics of capitalism and the the philosophy of liberal humanism. Adaptation, on the other hand, means adjusting to the conditions of a changed climate but not necessarily changing its causation and certainly not changing the fundamentally-modern belief in techno scientific rationality to solve our environmental and socio-economic problems.

Per McHarg, adaptation means fitting ourselves benignly into the landscape. But this now seems way too pastoral for a planet of 8 billion people in the throes of rapid climate change. More likely and more frightening is that adaptation will become the rationale for climate engineering: regulating the albedo of the atmosphere and the chemistry of the oceans, and planning vast landscapes so they not only feed us, but also help stabilize the carbon and nitrogen cycles.

Both adaptation and mitigation point towards what is now routinely referred to as resilience. Even though in the illustrative diagram I am situating resilience equidistant between adaptation and mitigation, I think resilience theory and practice tends more towards adaptation than it does mitigation.

The reason for this is that the utopia of sustainability, which is what mitigation implies, has by now proven itself to be something of an impossibility. Accordingly, resilience has been criticized as sustainability without hope. In other words, for its critics, resilience is seen as abandoning any possibility of mitigating the environmental and social crises of modernity. Instead, we, and in particular the poor, must now learn to live with the symptoms. In this sense resilience is palliative, conservative, and at worst complicit in preserving the very systems that created the risk in the first place.

Maybe so, but this is all a little too black and white. I would also add that resilience is realistic, whereas mitigation is hopelessly idealistic. Resilience brings sustainability closer to the indeterminate way that both the natural and cultural worlds actually work. Whereas sustainability was based on an idealized ecology of equilibrium, resilience is based on an interpretation of nature as a state of disequilibrium. I think McHarg hoped ultimately for a world of equilibrium between the natural and the cultural but seems now that this is just not the way the world works.

Turning briefly now to the projects in the Design with Nature Now exhibition, there are two particular aspects of McHarg’s legacy that I want to channel. The first is his aspiration for large-scale impact and the second is his anticipation and use of digital technology. The first is what I call Big Plans and the second is Digital Natures.

Let’s start with Big Plans. On the map below, Global Landscape Connectivity Projects, you see most of the major conservation projects planned or under construction in the world today. This is an extraordinary image because it shows humans now, for the first time in (modern) history, actively and intentionally reconstructing ecosystems at a planetary scale – so yes, effectively designing a planet, or at least treating it as a garden instead of a mine. (See larger map).

Global Landscape Connectivity Projects / Richard Weller, Claire Hoch, and Chieh Huang

McHarg would love this map and it should give us all hope. And yet from a professional perspective much of this restorative activity doesn’t currently involve landscape architects. That we think it should is why we’ve included projects such as the Yellowstone to Yukon (Y2Y) Conservation Initiative in the United States and the Great Green Wall across sub-Saharan Africa in the exhibition.

Yellowstone to Yukon (Y2Y) Conservation Initiative / Y2Y.net
Great Green Wall / United Nations Food and Agriculture Organization (FAO)

For example, the Y2Y is a remarkable ongoing story of collaboration (and tension) between land owners over some 2,000 miles of territory in order to create landscape connectivity for species migration. The Great Green Wall is also a remarkable story of what began as a top-down initiative to resist the southward encroachment of the Saharan desert but has since evolved in to a mosaic of bottom-up initiatives to boost local agrarian economies across the 14 impoverished nations it comprises. When completed, if ever that day comes, the Great Green Wall will be the largest living thing ever created by humanity.

A third Big Plan, I’d like to single out that is versed in McHargian methods is the 2008 National Ecological Security Patterns for the whole of China by landscape architecture firm Turenscape, which was founded by Kongjian Yu, FASLA, and the Peking University Graduate School of Landscape Architecture. The plan shows where the ecological security of land in China should be prioritized.

Framework for national security ecological patterns / Turenscape
Ecological security pattern for biodiversity conservation / Turenscape

This research coincides with President Xi Jinping’s 2013 declaration that China should transition from a Gross Domestic Product (GDP)-focused civilization to an ecological civilization. And in this regard, while the study represents a powerful breakthrough for landscape architects, it is also something of a Faustian bargain. It raises the question of whether plans done in the name of national ecological health for totalitarian governments could come to overrule local culture in the same way development projects previously did in the name of the national interest. Imagine mass evictions not for hydroelectric dams, but now for biodiversity corridors.

Regarding the second aspect of McHarg’s legacy, the theme of Digital Natures relates to how landscape architects today are increasingly able to simulate environmental conditions in order to guide design decisions. There are two aspects to this. The first is the ability to create one’s own data instead of just passively receiving it from an authority, and the second is the increasing capacity to model complex, chaotic systems such as hydrology, and perhaps eventually entire ecosystems, cities, and ultimately the Earth system itself, as we see in the case of the book Global Change and the Earth System.

The key here is being able to model systems in the fourth, not just the third, dimension. That is, we are moving into an era where the old problem of a map being redundant the moment it is drawn can finally be overcome. It is early days in the emergence of the genre of Digital Natures, but the work of academic practitioners such as Keith Van Der Sys, Karen M’Closkey, Bradley Cantrell, ASLA, Justine Holzman, Sean Burkholder and Brian Davis — all of whom are variously modelling fluvial landscapes — is promising.

For example, the Healthy Port Futures project in the Design with Nature Now exhibition by Burkholder and Davis foregrounds digital modelling to predict sediment flows in the world’s largest inland water body, the Great Lakes of the USA and Canada. The project centers on creating simulations to show how instead of being treated as a useless waste product, sediment can be redirected so as to create new landscapes of ecological and social value. Stemming out of the academic Dredgefest initiative, Burkholder and Davis’ work is significant for its methods and also because with it they are muscling their way into territory otherwise dominated by engineers.

Contextually calibrated alternatives for passive sediment management for Lorain, Ohio / Sean Burkholder and Brian Davis: Healthy Port Futures

Which leads to what is for me the most extraordinary and perhaps the most compelling work in the exhibition: the so called Sand Motor (Zandmotor) constructed in 2011 off the coast of the Netherlands. The Sand Motor is a novel approach to coastline protection in which sand is mined offshore and added to the beach at a strategic location so that the littoral drift steadily redistributes the material further along the coast, thus reinforcing Holland’s coast against the sea. This could only be done through predictive modelling of the coastal system. Absent recent advancements in computing power, such analysis would have been previously prohibitive. Now, not only could the Sand Motor’s behavior be accurately predicted before it was built, it is also continually monitored, establishing a feedback loop between the digital and the real.

Zandmotor by Rijkswaterstaat

The Sand Motor marks a new technological and predictive level of human engagement with the environment, one that will expand at both macro and micro scales this century. In addition to designing gardens, parks, and plazas as we always will, the kind of systems design the Sand Motor suggests it is as foreboding as it is promising.

Even if unintentionally, the sand motor is also, I think, a highly aesthetic work. In fact, I’d go so far as to say it is one of the great artworks of the early Anthropocene, something land artist Robert Smithson pointed to 50 years ago. I imagine a scene where Professor Marcel Stive, the lead engineer of the Sand Motor, now replaces Caspar David Friedrich’s Monk by the Sea, not to contemplate God’s awesome creation, but rather ours.

And that brings me full circle to where I began with origin of the Anthropos. For if we have now become Gods then, for all their complexity and contradiction, I do think the projects in the exhibition show that we can be good at it.

This post is by Richard Weller, ASLA, the Martin and Margy Meyerson chair of urbanism, professor and chair of landscape architecture, and co-director of the McHarg Center for Urbanism and Ecology at the University of Pennsylvania.

Landscape Architecture in the News Highlights (August 1 – 15)

Elizabeth Meyer, FASLA, the 19th recipient of the National Building Museum’s Vincent Scully Prize / Landscape Architecture Magazine

To Combat Climate Change, Cities Need to Tackle SprawlCurbed, 8/8/19
“A new IPCC report offers a stark reminder that land use policy needs to be radically changed.”

Italian Architect Stefano Boeri Unveils Plans for Africa’s First “Vertical Forest”CNN, 8/6/19
“Home to the ancient pyramids, Egypt is no stranger to architectural innovation. So it is no surprise that it is set to become the first African nation to host a “vertical forest.”

The Cultural Landscape Foundation Launches Major international Design PrizeThe Architect’s Newspaper, 8/12/19
“Landscape architects, artists, and architects, as well as urban planners and designers, are encouraged to apply for the inaugural prize, set to be chosen in 2021.”

Preparing, Updating an Impactful Landscape Architecture PortfolioTotal Landscape Care, 8/13/19
“Whether you’re new on the landscape architecture scene or have been working in the field for many years, having an impressive and updated portfolio is important.”

How Landscape Architecture Hoped to Save the City Metropolis, 8/13/19
“An exhibition at the Isabella Stewart Gardner Museum explores the intersection of landscape architecture and social reform at the turn of the 20th century.”

National Building Museum Awards 19th Vincent Scully Prize to Elizabeth Meyer – Architect, 8/13/19
“Today, the National Building Museum (NBM) announced landscape architect Elizabeth K. Meyer as the 19th recipient of the Vincent Scully Prize.”

More Climate Surprises Expected

Sargassum seaweed in the Gulf of Mexico / NASA, Michael Stein

After the White House suppressed his Congressional testimony on climate change and national security, Dr. Rod Schoonover, a scientist and analyst with the State Department’s bureau of intelligence and research, resigned in protest. Nearly three weeks after his resignation, Schoonover discussed the substance of his testimony with Andrew Light, senior fellow at the World Resources Institute (WRI). His primary conclusions: the U.S. and other countries can expect more “climate-linked surprises;” climate change will cause much more than weather-related impacts, and combined with environmental, social, and political events will become a national security “threat multiplier.”

In a June briefing, the White House allowed Dr. Schoonover to give oral testimony, but blocked the submission of his written testimony drafted on behalf of the bureau into the permanent Congressional record. In internal administration emails uncovered by The New York Times, the reasoning for this was the testimony included science that didn’t correspond with White House policy views. The White House called the testimony part of the “climate alarmist establishment.”

Intelligence experts argue that any scientific analysis included in a risk assessment is by nature objective and rooted in mainstream, peer-reviewed findings. The White House’s actions constituted a “suppression of factual analysis by a government intelligence agency.” And According to The Times, the State department’s bureau of intelligence and research is viewed as one of the most “scrupulous and accurate” in the federal government.

In his conversation with Light, Dr. Schoonover said the U.S. intelligence community has been testifying on the coming impacts of climate change since at least the late 90s, so “this is not new territory.”

National security policy decision making is increasingly of a “technical nature.” Therefore, to give policymakers the best analyses, the intelligence community must incorporate the latest science. The intelligence community doesn’t generate the science, but must interpret it objectively. “We need scientists in the U.S. government to stay current. We need scientists to help us understand nuclear, infectious disease, near space objects, and climate change.”

Light said it has been 12 years since the Center for Naval Analysis and the Military Advisory Board published National Security and the Threat of Climate Change, which identified climate change as a threat multiplier. “Since then, the attribution science, isolating the degree to which climate change has an impact, has only improved.” Another study published in 2015 in the Proceedings of the National Academy of Sciences (PNAS) linked climate change, drought, and the onset of civil war in Syria. And in a recent worldwide threat assessment presented to Congress, now-former director of national intelligence Dan Coats identified hot spots where climate change could create conflict, such as Egypt and Sudan.

Dr. Schoonover, who gave up a tenured position teaching complex systems at California Polytechnic State University to work at the federal government, made a few key points that he wasn’t able to elaborate in his abridged Congressional testimony:

The U.S. and other countries should expect more “climate-linked surprises,” which are events with low probabilities but high impacts. For example, no one could have predicted that deforestation in Brazil would lead to fertilizer runoff in the Atlantic Ocean to mix with warming oceanic currents and create massive Sargassum seaweed blooms that would then cover the beaches of the small island nations in the Caribbean. Tons of seaweed now wash up on beaches across the Caribbean every day. “For these countries, Sargassum is a national security threat, as it impacts tourism and economic vitality, strangling their resources.” This is an example of a “surprise element that came out of nowhere. Very rapid changes could occur with dramatic impacts.”

Non-weather climate stressors also create national security risks. He called for moving past a “weather-centric” approach that solely focuses on sea level rise, drought, wildfires, and extreme heat. Peer-reviewed scientific studies find that climate change will also impact ecological food webs and cause mass extinctions and biodiversity loss, which will negatively impact human food systems. Climate change will also impact human health by changing the ranges of infectious disease vectors like mosquitoes. Like with Syria, there is the risk that weather-related climate impacts, such as drought, will cause political and social instability and increase violence.

A final important point: “the bundle of issues is what’s important. Climate change together with environmental degradation and social and political instability is the threat multiplier.”

Global Reforestation Could Drawdown Carbon but Also Jeopardize Water Supplies

2880px-Eucalyptus_plantation_in_final_stages
Eucalyptus Plantation in Arimalam, India / Wikipedia

In the global scramble to reduce carbon emissions, planting more trees is always near the top of the list of solutions. Pegged as a low-cost, natural, and scalable approach, projects like the Great Green Wall in North Africa, Pakistan’s 10 Billion Tree Tsunami, and New York City’s Million Tree Program raise the bar for this climate change mitigation strategy. While a new scientific study found there is untapped potential for carbon sequestration through planetary reforestation, other researchers are concerned about how growing new forests could reduce the focus on preserving existing old growth forests or negatively impact the water supply in developing countries.

The recent study published in Science, led by Thomas W. Crowther at ETH-Zürich, posits that an increase in 0.9 billion hectares (2.2 billion acres) of new forests, an amount that would cover about 14 percent of habitable land, could sequester 205 gigatons of carbon from the atmosphere. This means a forest roughly the size of the United States or China could sequester more than five times the annual carbon output of the planet.

Under current climate conditions, the Earth could support a maximum of 4.4 billion hectares (10.9 billion acres) of forests. Approximately 2.8 billion hectares (6.9 billion acres) are currently forested. This leaves 1.6 billion hectares (4 billion acres) were additional forest could be planted. The research team removed land used for crop-based agriculture or cities,”which are necessary for supporting an ever-growing human population,” leaving 0.9 billion hectares (2.2 billion acres) available for forest restoration.

Across the lifetime of these proposed new forests, the trees would sequester 205 gigatons of carbon from the atmosphere. For reference, we have released 1,510 gigatons of carbon to date (as of 2015), and some 55 percent of that has been sequestered by oceans and plants.

A sequestration strategy of this magnitude would make a sizable dent in the total carbon released into the atmosphere, but needs to be matched with reductions in fossil fuel use and other major forms of greenhouse gas emissions. The World Resources Institute (WRI) reports that 37.1 gigatons of carbon were released in 2018 alone. At this rate, more carbon will be released than can be captured by the new forests during the 50-100 years it will take for the trees to mature.

Reforestation
A 15-year old reforestation project, U.S. / Wikipedia

The research team is correct in asserting that global tree restoration is “our most effective climate change solution to date,” but some researchers fear that addressing one warning light may turn on others.

For example, focusing on planting new forests instead of preserving old growth trees can have negative impacts. Large, old trees, which support greater biodiversity and sequester more carbon than younger trees, are “declining in forests of all latitudes,” according to a 2012 study. Old growth forests are able to sequester more carbon than their younger counterparts because they are still rapidly growing and increasing their carbon storage capacity. Preserving older forests while implementing massive reforestation efforts would yield the greatest potential for carbon capture and forest ecosystem health.

Protecting large old trees is an important part of the climate mitigation effort, and something that landscape architects working at a variety of scales can support. Every reforestation effort, even in an urban park, should take into account existing trees and the role they play in ecosystems.

General_Sherman_Tree
General Sherman Tree, the largest living tree by volume / Wikipedia

Trees need water to thrive. The renewed call for mass reforestation across the globe has some researchers worried about the effect this will have on local water supplies.

In a recent study published in Nature, Jaivime Evaristo and Jeffery J. McDonnell examine the impact of forest management practices, such as deforestation, conversion into agricultural land, regrowth, and afforestation (growing new forests), on the availability of water in watersheds. The study develops a vegetation-to-bedrock model, which considers the geology of a given region in relation to its capacity to store water.

The researchers found that deforestation and conversion of forests into agricultural land increases the volume of water present in almost all watersheds, while regrowth of forests and afforestation reduced the volume of water. “The vast majority of the water loss in afforested and reforested areas is from evapotranspiration, which is a combination of evaporation from soil and other surfaces and transpiration from plants.”

Afforestation and deforestation have the largest impacts on streamflow in watersheds. Deforestation can cause flash floods, but reforestation can lead to droughts.

The data also shows the percentage change in tree cover is correlated to the socio-economic status of a country. Developing and least developed countries lose the most tree cover while developed and emerging countries lose the least. The researchers think this correlation between tree-cover change and economic status “suggests that countries that have infrastructure in place for capturing and storing water may be least vulnerable to possible water supply shortages associated with planting schemes.”

Furthermore, the research team concludes the magnitude of a forest management technique is correlated with the water-yield response. Reforesting nearly 14 percent of the landmass is a massive change, one that would surely have consequences for local communities and ecosystems.

The researchers recognize their streamflow analysis could be used most prudently “for re-calibrating the cost-benefit matrix of climate change mitigation schemes (for example, planting and removal) in different geo-climate regions around the world.”