How understanding weather whiplash can help build climate resilience

By Rebecca Verity, Climate Adaptation Practice Leader

“If you know yourself but not the enemy, for every victory gained you will also suffer a defeat.” – Sun Tzu, The Art of War, 496 BC

It might seem odd to begin a blog about planning for weather whiplash with ancient battle wisdom, but the concept of knowing one’s enemy is critical to climate resilience.

The past few years have stretched our coping skills to breaking. Between the pandemic, and weather catastrophes so constant they barely make national news, we are all exhausted.  Whether you’re a city planner protecting residents, or a utility owner delivering lifeline services, you know there’s more risk planning to do.

When we’re overwhelmed like this, simple solutions appeal.  But, when we don’t “know our enemy,” simple solutions can have unintended consequences. For example, a landowner who clear cuts a hillside to reduce wildfire risk may hasten a landslide.   To help avoid these unintended consequences, I’ll elaborate on two concepts:

Know your enemy: When the enemy is weather whiplash, illuminating the connection between two or more seemingly opposite catastrophes is critical. So, when we build resilience to the first, we also account for the next.

Plan for success: By following five discrete, practical steps for resilience planning, we can avoid common pitfalls and respond, rather than react, when emergencies occur.

Let’s start with understanding weather whiplash – what it is and why it occurs.

Weather whiplash: the pain experienced when seemingly opposite climate extremes slam into a community rapidly and in quick succession. Examples include:

4 December, 2017.  A severe drought grips Southern California, spawning the Thomas fire, an inferno so fierce it spawned its own weather, and destroyed 440 square miles, including the steep slopes above the coastal town of Montecito.

9 January, 2018.  The first rains finally appear in a deluge, drenching Montecito. The fire-scorched slopes slip into a river of mud (aka debris flow), overwhelming the town, killing 23, and destroying or damaging more than 400 homes.

Examples of weather whiplash aren’t new, but they used to be cautionary tales. No longer. Let’s examine why, using that now familiar drought/ fire/ deluge/ debris flow pattern.

These patterns don’t happen because of bad luck or unusual odds. They happen because each of the components of our climate are intricately linked. The links between drought and flood in the arid US West are extraordinarily tight, and they are tied by temperature.

 Seven Steps to Drought/Flood Whiplash

1. As temperatures increase so does evaporation.
2. Soils dry faster and more completely after rains.
3. Hot, arid soils whither plants, reducing shade and increasing local temperatures.
4. Low moisture and parched plants mean wildfires spark more easily, burn hotter, and spread more quickly.
5. As temperatures increase, air holds more water. For each 1° C increase, the atmosphere holds 7 per cent more water vapor.  This means that, once rainstorms finally form, they are often atmospheric rivers: drenching, flooding rain and massive snowpack.
6. Warming temperatures bring shorter winters and earlier springs: when February and March are wet and warm, rains quickly melt the snowpack that historically lasted through June. Combined rain and snowmelt turning flooding rivers into torrents. Reservoirs are overwhelmed; to avoid catastrophic dam failures, operators must open spillways and send that precious water to the sea, rather than catching and storing it for summer. With no snowpack left, reservoirs begin to shrink in spring, rather than late summer.
7. Without snow, soils dry sooner, the drought deepens, and the cycle continues.

The Oroville Reservoir at capacity prior to a catastrophic dam failure of 2017, vs. Oroville Reservoir during the catastrophic drought of 2021 – Photo Source:  Source: California Department of Water & Power

 

Clarifying these relationships helps us shift from a reactionary, micro-focus to a wider perspective for strong planning, with a better understanding of the breadth of risks we must address.

Five steps for smart resilience planning:

1. Plan for crises in advance. Commit to understanding and avoiding linked risks in future response plans.  If your community or business is not currently in crisis, now is the time to plan, so that when weather hits, you are ready. Use this time to:
   1. Update policies and plans for how we respond in the moment of an emergency,
   2. Update how we design and build
   3. Prepare redundancy for lifeline services and assets, wherever failure of one element is likely to exacerbate harm
2. Invest early in resilience. Building for big weather ahead of disasters not only saves lives but, as the insurance industry is experiencing, it also saves significant money.
   • Identify emergency response resource needs
   • Find partners – neighboring communities, related agencies, utilities and service providers, and share resources. Partnering on grant applications is a particularly savvy move.
3. Aim for multi-benefit when designing resilience strategies. Look for solutions that address multiple concerns to maximize success and return on investment. Examples:
   • Need to increase community water storage? Groundwater recharge is less vulnerable to flood catastrophes than building new reservoirs, and groundwater recharge has additional benefits.
   • Need to protect against rising seas? Design seawalls which don’t trap catastrophic rain during hurricanes.
   • Need to protect against wildfire? Clear-cutting adds new risks. Create “shaded fuel breaks” to reduce ladder fuels while keeping soils cool and ecosystems sound.
4. Avoid analysis paralysis. Often, crisis planning waits for projections and probabilities from elaborate custom models. It needn’t. Use existing tools and information on regional risks, and start with how we already plan for hurricanes and earthquakes. We don’t build to survive a Category 2 hurricane or a Richter Scale 4 earthquake: we build resilience to “the big one.” That’s a smart approach to climate planning, as well.
5. Recognize that disasters rarely hit equitably. Neither should solutions. Mandatory water rate hikes, for instance, may cost one family their fountain, and another their home.
   • Consider which portions of a community are most at risk, and include them in conversations, early and often.
   • Prioritize the needs of the most vulnerable.
   • Pair new taxes, tariffs, building codes, rate hikes, and penalties with exemptions, tiers, rebates, and assistance as necessary.

Now that our climate regularly encompasses extremes, our ideas, partnerships, plans and designs must expand as well. Working together, we can make it happen.

If you have a specific question about how to implement these steps in your community, please reach out. rverity@geiconsultants.com