Adaptive Design for Climate Change
All of our work anticipates a more rapidly changing climate and aims to develop farm and residential land use systems that will be adaptive and resilient in the face of these and other shifting conditions.
Climate Change Design Strategies
By Ben Falk, M.A.L.D.
The Earth orbits the Sun at distances that vary by 3,000,000 miles across the year. Volcanoes explode, ice fields melt, sea vents open and close, gasses continually exchange between rock and plants, ocean and atmosphere. Human influence is only one factor in Earth’s climate stability. Accurately engaging the issue of ‘global climate change’ requires an understanding that the Earth’s climate has never done anything but change. With this in mind we move forward knowing that if the human project is to be successful on planet Earth, it will be highly adaptive in the face of change.
Design for Change
Good design is design for change. Good design is structurally diverse and not depend on any single element for its overall success. Good, whole systems design, harnesses the forces of evolution and includes both the built and biological environment. This article briefly overviews strategies for developing biologically – adaptive, intentional ecosystems (permacultures) and climate-buffering landscapes (microclimates) in which humans can build homes, produce food, and live well, in a future of greater adversity, or not.
Climate change is occurring more rapidly today than in thousands of years. Research indicates that the climate has been unusually stable for the past 10,000 and even more so for the past 100 years. The design challenge is clear: Develop a whole resource landscape (built and biological) that will be resilient within a wide range of conditions. What specific challenges should we design for? These include: longer droughts, hotter summers, colder winters, higher winds, increased pest success, heavier precipitation, earlier and later frosts, and other irregularities (which have always tested humanity’s ability to thrive and survive on this planet).
Specific Climate Challenges
High performance landscapes and buildings are designed to meet the following characteristics of Earth’s changing climate. Many of these challenges are already occurring in the New England:
• Precipitation via disastrous forms (e.g. high volumes of rain, snow, hail)
• Increasing likelihood of soil erosion by flooding
• Increasing heating and cooling needs
• Increasing severity and probability of high wind events
• Increasing overall success of pests
• Decreasing influence of pollinators
• Increasing likelihood of drought conditions
• Increasing likelihood of annual crop failure due to spring flooding
• Increasing extremes of aridity and humidity
• Increasing probability of early flowering and fruit-set, and consequent crop failure from frost damage
Neither predominant agricultural models nor common housing and transportation systems are designed to withstand significant climate changes. Landscape level developments that intentionally adapts to these changes employ the following components among others:
1. Microclimate development including windbreaks, snow-retaining hedgerows, thermal mass via water and stone, and sun-trapping vegetated and/or built arcs. These systems provide a buffer against regional climatic stresses by localizing climate at the site level.
2. High biodiversity of crop species from neighboring warmer and colder climate zones (U.S.D.A. hardiness zones /- 2 zones). Such polycultural diversity supports the resilience of the farm system at the species level, and the adaptability of crop genetics at the varietal level. This genetic complexity helps revive the loss of crop diversity caused by monoculture in the 20th century while adding to the abundance of foods we have to choose from.
A microclimate is any discrete area within a larger area of differing climate. Microclimates exist unintentionally in “nature,” but good design creates microclimates intentionally. Since cold is a limiting factor (along with light) in producing food and sustainably inhabiting the New England landscape, developing warm microclimates is the priority. Cooling strategies, however, will likely become increasingly important, especially in southern New England, if conditions continue to warm.
Optimized microclimates can result in the following:
• Lower active energy needs for buildings: less fuel, less cost, less pollution. Example: Passive solar house within a passive solar landscape.
• Longer growing seasons relative to the surrounding environment. Example: Climate-designed garden spaces that stay frost free for weeks longer in the spring and fall than adjacent areas.
• Higher yields from plants and animals – better growing conditions. Examples: Warmer environment for heat-loving crops; cool-shaded spaces for domestic animals in the hot summer; Wind sheltered spaces for animals and buildings.
• More enjoyable, lower stress and healthier human habitats. Longer outdoor living season; more fresh air; more contact with water, plants, living systems; and greater physical activity and mental stimulation. Example: Outdoor living spaces optimized to be cool in the summer, warm in the winter.
Microclimate Development Strategies
The first step in crafting beneficial microclimates is proper site selection. Some landscape features cannot be changed at all or only to a small extent. The second step in localizing your climate is site design. Once a site has been chosen a handful of strategies, planned for and implemented carefully, can optimize the existing climate of the site to more fully meet the needs of the site’s inhabitants.
Design of warm microclimates checklist:
- Face-southerly and avoid cold air drainages and dams
- South – southwest = warmest
- Slope/Vertical Space Harvesting
- The further poleward the steeper the slope should be to capture the most solar energy
- Bowl – solar arc/sun trap
- Utilize energy-harvesting forms
- Minimize radiative losses – provide cover
- Nighttime losses of heat are the most difficult to avoid
- Buffer and deflect, create eddies, preserve and enhance hedgerows
- Stone and water are the primary heat-retaining materials
- High absorption (low albedo)
- Utilize color effectively
- Time your microclimate
- Design for a particular time of day and year, usually whenever limiting factors are most present
Examples of microclimate-creating features of a place are: hills, fields, trees, cliffs/stone, gullies, ridges, groundwater, ponds, lakes, roads, walls, lawns, roofs, courtyards. Employing such features in the development of climate-protected spaces is more effective than attempting to create new microclimates from scratch.
Of primary importance for increased food security and regional resilience is developing diverse and flexible food crops. Climate changes can deliver periods punctuated by both extreme heat and cold within the same year. The following strategies highlight the benefits of high biodiversity polycultural food systems.
Early and late frosts, intensifying drought, heat and cold, and other stresses select against certain crops. A broad range of species with different flowering cues and hardiness capabilities is insurance against poor fruit-sets, pollination failure and other problems due to capricious weather. Genetic diversity in species and variety is fundamental to a resilient ecological system.
Developing innovative new cross breeds also helps to ensure resiliency of food systems. For example, crossing a sweet cherry (Prunus avium) with a Nanking cherry (Prunus tomentosa) can create a next-generation cross which flowers like the Nanking cherry (late, thus avoiding the killing late spring frosts) but has the larger , sweeter, and more marketable cherry.
Warmer and Colder Hardy Crops
Rapidly warming and cooling trends will likely outpace the agility of current agricultural systems. Durable farming system would plan for temperatures up to 10-15 degrees warmer or colder. Imagine Zone 4 becoming just 10-15 degrees warmer (an average low of -10 F): A diversity of bamboos, palms and bananas could be grown. Some apples and native plums can withstand negative 50 degrees F. or colder (depending on rootstock) – a nice feature if the global ocean conveyor belt stops or changes direction.
Why not view the inevitable changes of Earth’s global climate as a call to action and as a challenge to increase biological diversity and ecological resiliency? We can face this challenge squarely and allow it to focus our minds, communities, and our creative abilities on the development of more resilient approaches to living on this planet.