Attribution and contribution
With ‘wild’fires still raging across southern California, Gov. Jerry Brown warns that megafires may be the new normal.
A cursory glance at media coverage over the past few years shows a trend of (thankfully) moving past “does climate change exist?” toward “is climate change to blame for this disaster?” Recent examples include VOX’s ‘Climate change did not “cause” Harvey or Irma, but it’s a huge part of the story‘. This, and Gov. Brown’s recent warnings are classic examples of the tensions between attribution and contribution.
While ascribing direct responsibility for particular events, or “impacts attribution”, is challenging, creating the preconditions for them to occur or to be more intense or prolonged – such the higher winds and a overall drier season that have driven the Skirball and Thomas fires, threatening nearly 200,000 acres in California – is easier to justify.
We’ll discuss mitigation – or the drive to limit human (anthropogenic) emissions of greenhouse gases – in a future post. Yeah, that’s you: You ain’t off the hook just yet…
In the meantime, The American Meteorological Society’s ‘Explaining Extreme Events from a Climate Perspective‘ is an excellent primer on attribution and contribution.
I would argue, however, that making this distinction isn’t always useful. Do we focus on whether boiling water is directly responsible for producing a hard-boiled egg versus creating the preconditions of temperature and moisture to transform a delicate poultry product into an edible snack you can hold in your hand? (make sure it cools, first!)
The first point is, rather, not to get too hung up on causation for particular events, but rather to acknowledge the changing climate as a driver and contributor to making natural events events such as wildfires, droughts, and flooding more severe.
The second and, arguably, more important point is to plan accordingly, rather than wring our collective hands in despair. Wildfires have been experienced by – and often used by – human civilization for centuries. Using ‘disasters’ as course-corrections is critical, and actually something societies usually do quite well. While it may be cold comfort for those currently affected, building codes, for example, have usually improved after tragic events.
This leads us another consideration: why I keep putting quotes around ‘wild’ in wildfire.
Urban fire or ‘wild’fire?
I worked in Haiti after the 7.0 magnitude earthquake of 2010.
Relief agencies were often flummoxed with how to respond and, more importantly, how to develop long-term recovery solutions. Why? Because this was one of the first – and worst – extensively urban disasters. Their experience was mostly with rural areas, so recovery housing typologies and approaches were ill-suited in the early days of recovery.
I mention this less to make a distinction between urban and non-urban, but to argue that the latest California fires are not ‘wild’fires – they are urban fires.
Bel-Air’s population density is 7,691 people per square miles. Santa Barbara’s population density is 4,716. Ojai’s is 1,773.
Sure, they ain’t San Francisco (18,573/square mile) or Chicago (11,898), both of which are un-arguably urban and two of the most famous cities that recovered from terrible urban fires and instituted exemplary fire codes. We could split hairs and consider the fires that have threatened Bel-Air, Santa Barbara, and Ojai to be suburban fires. The point is that the recent fires cannot be considered simply ‘wildfires’. That term connotes a large, destructive fire that spreads quickly over woodland or brush.
Look at the photo above: while chaparral and brush may be (or have been) present, so are (or were) people’s homes.
More specifically, the concept of the wildland–urban interface (or WUI), according to Radeloff et al. (2005) “refers to the zone of transition between unoccupied land and human development. Communities that are within 0.5 miles (0.80 km) of the zone may also be included.” It’s a good term. And this fall and winter we are seeing the frontlines of the wildland-urban interface brought directly to the doorstep of many people.
However, what matters is less how terminology affects how fire is classified, but rather how it is managed.
My third point is to consider better and more strategic land use planning and management, more savvy landscape, residential, and commercial design as part of that ‘new normal’ Gov. Brown forsees.
Let’s hope the lessons of California fires help us refine a more nimble approach to events which are naturally occurring, and occurring more often and more intensely.