Professors Ruhl and Craig paint a vision of a 4ºC world marked by “discontinuous and often unpredictable transformation.” Nature, from climate to ecosystems to species, is hard to predict in the best of times. It’s a wild beast in a 4ºC world. This means that we will have to give up our efforts to tightly control nature and instead give her room. Room in a real, physical sense, like space for species to migrate and for seas to rise and for rivers to roam; and room in a metaphorical sense, by not harvesting and managing and controlling and consuming right up to the edge of destruction.
The only certain thing in this uncertain 4ºC future is change: The weather in many locations will be marked by increased variability, higher temperatures, more extreme precipitation events, and changes in total precipitation. Sea levels will rise. Storms will be more intense. In short, climate change will make many of our current climate expectations obsolete. Moreover, a 4ºC world does not just present a new set of stable conditions that society can assume will continue into the future; continuing unpredictable shifts in climate are a hallmark of a 4ºC world.
This is especially challenging because core aspects of our society, from infrastructure to farming to insurance to conservation, have been designed with the assumption of relatively predictable climate. Infrastructure, for example, is often tailored very narrowly to meet a predicted climate range, and flood insurance programs require levee protection designed to withstand a 100-year flood event in most areas. But in a 4ºC world, levees will face storms that exceed those design standards much more frequently than once every hundred years. We’ve often left ourselves a narrow margin of safety in all kinds of systems, from infrastructure to agriculture to environmental protection. This approach leaves little room for error, and the predictable climate that enabled this approach is ending. We’re moving into a climate that is predictably unpredictable. Our current world of just-in-time delivery, thin margins, efficiency, precise timing, and long supply chains is not built for the uncertainties of a 4ºC future. This problem extends to the ways we currently manage ecosystems, approaches that leave little room for nature itself.
Professor Dave Owen describes the prevailing ecosystem management ethos as “allow[ing] resource consumption right up to perceived brinks of illegality and . . . provid[ing[ just enough protection to avoid legal violations, but no more.” Managing at the brink of illegality is part of a broader problem of trying to manage natural systems within carefully delineated boundaries, under tight control. Of course, we actively manage ecosystems to protect particular species or provide particular ecosystem goods and services. But in many cases, as Professor Owen describes, we try to do so with little room for error, giving ecosystems only enough to deliver what we seek. Examples include just-in-time delivery of habitat for migrating birds, the deployment of just-in-time water management for fish protection, the provision of just enough protection for species to avoid a jeopardy opinion under the Endangered Species Act, and limitations on protections for desirable species to small habitat areas on the assumption that managers can unfailingly provide the precise conditions the species require.
The inclination toward these approaches is entirely understandable. They present the irresistible promise of using science, technology, and engineering in real time to meet the needs of nature while putting as few constraints on human activities as possible. Who doesn’t want more with less? In so many ways, it fits with our cultural zeitgeist. Even under current conditions, though, this approach often falls apart in the face of uncertainty and the inherent challenges of predicting natural system responses. And when these kinds of efforts fail, they generally place the burden of failure on ecosystems and species; they are not safe-to-fail approaches.
In an uncertain 4ºC world, tight management to achieve a narrow range of ecosystem conditions will be both increasingly expensive and increasingly impossible. The nature or character of an ecosystem is determined based on physical characteristics of the ecosystem, like precipitation, soil characteristics, temperatures, and on species availability (what gets introduced to the ecosystem) and the interactions between the species that find their way into the ecosystem. Changing any of those aspects of an ecosystem can produce a cascade of changes throughout the whole of the ecosystem, altering ecosystem aspects such as the abundance and kinds of species present as well as physical conditions in the ecosystem.
Climate change is already producing widespread changes in ecosystem conditions. Predicting exactly how a particular ecosystem will react to these changes is very difficult, but scientists can nevertheless predict that change is very likely. For example, based on increasing temperatures alone, more than one in every three local species in the Americas will be different in ninety years. The ecosystems that will develop in a 4ºC world are unpredictable, with no analog in today’s ecosystems, and tightly managing those ecosystems to provide desired outcomes will be tremendously, well, uncertain.
Instead, managers must approach ecosystem management with humility, not an expectation of understanding and control. What, precisely, does managing with humility mean? I’m excited to flesh that out in future work, but as a baseline, humility counsels leaving time and space for nature. Physical space: Space for new wetlands. Space for rising seas. Space for shifting floodplains. Space for fire. Space for new species. Space and time for natural processes to develop and shift and adapt. And metaphorical space: relaxed expectations about our ability to control nature and predict the outcome of management actions, more conservative estimates of how species will respond to conservation efforts, more leeway in estimating water needs for nature, less belief in the power of science and engineering to replicate natural systems.
In some ways, leaving space for nature fits well with our 4ºC infrastructure challenges. Reconciliation ecology, defined by its originator Michael L. Rosenzweig as “the science of inventing, establishing and maintaining new habitats to conserve species diversity in places where people live, work and play,” provides ways to integrate human and natural systems needs. Thus, to use one example, perhaps “space for wetlands and floodplains” becomes building sea walls and levees set far enough back from coasts and rivers to provide both improved flood protection and space for nature. Moreover, we must also consider how to integrate the inevitable human migration with healthy ecosystems: as people migrate to more hospitable places, we must leave room for nature in the new developments. And, although perhaps it is more restoration than reconciliation, as we manage our retreat from places made unlivable by climate change, we must not salt the earth, but rather rewild the lands and waters we leave behind.
Some states have begun to embrace this approach in their climate adaptation plans. California, for example, lists “prioritize natural infrastructure solutions” as one of its seven overarching principles for climate change adaptation and highlights the importance of restoration and conservation of natural systems to successful adaptation. This is a good start. But more broadly, we must recognize that tight controls of all kinds will fail in a 4ºC future, that the ecosystems of the future will not be the ecosystems of the present, and that nature needs space if it is to continue supporting life in the ways we have come to expect.
- Karrigan Bork, Acting Professor of Law at the UC Davis School of Law