California is grappling with an accelerating climate crisis, swinging between torrential rains and devastating droughts. This phenomenon, termed “hydroclimate whiplash,” has become a hallmark of a warming planet.
In the winter of 2022-23, California experienced unprecedented rainfall. Dozens of atmospheric rivers battered the state, flooding valleys, burying mountain towns in snow, and triggering landslides.
The once-in-a-lifetime precipitation event showcased the extremes of a changing climate. Yet, it was only part of a larger, more troubling cycle.
By 2024, southern California faced a record-hot summer and a dry start to the rainy season in 2025. The vegetation that had flourished during the wet winters dried into highly flammable fuel.
This “bloom-and-burn” cycle exemplifies the dual risks posed by hydroclimate whiplash: floods and fires.
HYDROCLIMATE WHIPLASH: A GLOBAL PHENOMENON
Hydroclimate whiplash refers to rapid shifts between extreme wet and dry weather. These shifts have grown more frequent due to climate change. A study published in Nature Reviews reveals that whiplash has increased globally by 31% to 66% since the mid-20th century.
Expanding Atmospheric Sponge
A primary driver of whiplash is the atmosphere’s growing capacity to absorb and release water. This is known as the “atmospheric sponge” effect.
For every degree Celsius of warming, the atmosphere holds 7% more water. This intensifies rainfall during wet periods and evaporation during dry spells.
Global Impacts of Whiplash
Regions worldwide are feeling the effects, including:
- Northern Africa
- South Asia
- The tropical Pacific and Atlantic
This boom-and-bust cycle exacerbates floods, droughts, landslides, and wildfire risks, making water management increasingly complex.
CALIFORNIA’S UNIQUE VULNERABILITY
Hydroclimate whiplash amplifies fire risks in two ways:
- Rapid Vegetation Growth: Wet winters foster lush plant growth, creating fuel for fires.
- Intense Dry Spells: Hot, dry summers leave vegetation tinder-dry, ready to ignite.
While climate change hasn’t significantly altered Southern California’s wind events, it has extended fire seasons by drying vegetation. This overlap of dry conditions and high winds escalates fire severity.
LESSONS FROM THE PAST AND PLANNING FOR THE FUTURE
Hydroclimate swings have tested California’s water infrastructure. For example, the spring 2023 snowpack followed one of the driest three-year periods in a century.
Traditional water management strategies, such as quickly diverting floodwaters to the ocean, leave cities vulnerable during droughts. A co-management approach, addressing both flood and drought risks, is essential for future resilience.
GLOBAL CLIMATE CONNECTION
Human-driven global warming is the primary cause of hydroclimate whiplash. Rising temperatures amplify water cycle disruptions, worsening both floods and droughts. Under a high-warming scenario, California will experience more extreme wet and dry years by the century’s end. Reducing global warming could mitigate this risk.
CALL FOR URGENT ACTION
Hydroclimate whiplash demands immediate attention. From improving fire management to rethinking water infrastructure, holistic solutions are vital.
California’s battle with extreme weather is a harbinger of global challenges. Every fraction of a degree of warming we prevent will reduce the devastating impacts of hydroclimate whiplash.
