Parts of California are sinking at an alarmingly fast rate, due to both subsidence and rising sea levels.
A NASA-led team of scientists has analyzed the US’ most populous state, which is home to just under 40 million residents, and has estimated that sea levels could rise by as much as 17 inches by 2050 – that’s 1.4ft.
“In many parts of the world, like the reclaimed ground beneath San Francisco, the land is moving down faster than the sea itself is going up,” explained lead author Marin Govorcin, a remote sensing scientist at NASA’s Jet Propulsion Laboratory in Southern California.
Researchers from NASA’s Jet Propulsion Laboratory, from the California Institute of Technology, as well as the National Oceanic and Atmospheric Administration (NOAA), tracked California’s coast line through by using satellite radar and highlighted the hot spots.
In the San Francisco Bay Area, more specifically, San Rafael, Corte Madera, Foster City, and Bay Farm Island, they found that the land was subsiding at a rate of more than 0.4 inches (10 millimeters) every year.
Due to this subsidence, the lowest-lying parts of these areas could see sea levels rise by more than 17 inches by 2050.
The team published the study in Science Advances. The abstract read: “Coastal vertical land motion (VLM), including uplift and subsidence, can greatly alter relative sea level projections and flood mitigations plans.
“Yet, current projection frameworks, such as the IPCC Sixth Assessment Report, often underestimate VLM by relying on regional linear estimates.
“Using high-resolution (90-meter) satellite data from 2015 to 2023, we provide local VLM estimates for California and assess their contribution to sea level rise both now and in future.”
It continued: “Our findings reveal that regional estimates substantially understate sea level rise in parts of San Francisco and Los Angeles, projecting more than double the expected rise by 2050.
“Additionally, temporally variable (nonlinear) VLM, driven by factors such as hydrocarbon and groundwater extraction, can increase uncertainties in 2050 projections by up to 0.4 meters in certain areas of Los Angeles and San Diego.
“This study highlights the critical need to include local VLM and its uncertainties in sea level rise assessments to improve coastal management and ensure effective adaptation efforts.”
The team of researchers also projected that humans are also inducing local land motion which can increase uncertanties in sea level projections by as much as 15 inches every year, specifically in parts of the counties of Los Angeles and San Diego.
Source: unilad.com