A mega tsunami could strike the US with little warning: Understanding Cascadia, the danger zones, and how to get ready
Waiting. Biding its time. The Cascadia Subduction Zone, a sleeping giant beneath the Pacific Northwest, has remained eerily quiet for over 300 years. But when it finally awakens, it won't just be a powerful earthquake that hits the coastline.
A towering tsunami, land collapse, and flooding on a historic scale may soon follow.
What is the Cascadia Subduction Zone?
The Cascadia Subduction Zone is a massive fault line running from northern California through Oregon and Washington, and all the way to British Columbia. It's where the oceanic Juan de Fuca Plate is slowly slipping beneath the North American Plate. But the plates don't glide smoothly — they get stuck. That strain builds for centuries until it finally breaks loose in a massive earthquake.
The last major quake hit on January 26, 1700. Based on geological records, it likely had a magnitude between 8.7 and 9.2. That kind of power could strike again. According to the US National Seismic Hazard Model, there's now a 15% chance of a magnitude 8.0 or greater event within the next 50 years.
Areas at risk
When the rupture finally happens, it won't just cause violent shaking and a deadly tsunami. According to a new study published in the Proceedings of the National Academy of Sciences, coastal land across 24 estuaries from southern Washington to northern California could suddenly sink by up to 2.67 meters (8.76 feet).
As per reports, these high risk areas include Washington, Oregon, Northern California, Alaska and Hawaii.
"We talk about climate-driven sea level rise, which is occurring at three to four millimetres a year, and that does eventually add up," said Prof Tina Dura, the study's lead author, in an interview with
BBC Science Focus
. "But here we'll have two metres of sea level rise in minutes. Why aren't we talking about that more?"
That sinking, or subsidence, would permanently change the coastline.
Flood zones would dramatically expand — by as much as 300 km² (115 square miles) today. Areas from southern Washington to northern California could see permanent land drops, especially in low lying estuaries. This sinking land would make flooding worse and more widespread- even long after the tsunami has receded.
The Long-term fallout
Beyond the quake and tsunami, recovery efforts would be hampered by the new geography. Roads and emergency services may end up underwater.
Saltwater could poison farmland. Wetlands that once helped block storm surges could vanish.
A 2022 FEMA planning exercise estimated 5,800 deaths from the quake and another 8,000 from the tsunami. Over 618,000 buildings, including more than 2,000 schools and 100 key facilities, could be damaged or destroyed. The total projected economic impact? $134 billion.
Infrastructure now at risk includes:
5 airports
18 emergency facilities (schools, hospitals, fire stations)
8 wastewater treatment plants
1 electric substation
57 contaminant sources (gas stations, chemical plants, etc.)
Aftershocks that never stop
The study warns that even if the quake struck decades from now, its effects could be magnified by climate change.
By 2100, global sea levels are expected to rise another 60 cm (2 feet). In Cascadia, rising land has masked some of that rise — but when the quake hits and the land sinks, the sea will seem to rise instantly.
The study also estimates that if the quake happens in 2100, floodplains could triple compared to today, expanding by up to 370 km² (145 sq miles).
How can people prepare themselves?
There are no easy answers. Cascadia is a unique problem faced by seismologists as it is so quiet. No one can predict the exact date or time it can wreak havoc. In case of an emergency, there are a few things that residents near the coast need to remember to ensure their safety
Identifying and relocating vulnerable infrastructure
Educating the public on risks
Prepare an emergency kit, as the infrastructure will be destroyed
Practice and update your emergency plan every 6 months.
Write down emergency numbers; give copies to all family members.
Hashtags
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
The Hindu
a day ago
- The Hindu
Science for All: Phytoplankton overfed on iron pollution are depleting nutrients faster
A new study has unearthed strong observational evidence that industrial pollution is altering nutrient cycles and ecosystem boundaries in the ocean. According to the researchers, from across institutions in the U.S., iron released due to human activities enhances spring phytoplankton blooms as well as speeds up the rate at which nutrients are consumed. The changes may work in synergy with climate-driven ocean warming and stratification, speeding up the transition to nutrient-poor conditions across broader swaths of the ocean, they added. The team published its findings in Proceedings of the National Academy of Sciences on June 2. The authors conducted four oceanographic expeditions between 2016 and 2019 to measure dissolved iron and its isotopic composition. They also used satellite observations and gene expression analyses to understand the biological responses to the element's presence. The team collected data during three springtime cruises in 2016, 2017, and 2019 and one autumnal cruise in 2018 to track seasonal changes in iron chemistry. Team members measured the amount of dissolved iron in the water and its isotopic composition using trace-metal clean techniques and mass spectrometry. They also analysed metatranscriptomic data from phytoplankton samples to look for the expression of genes associated with iron stress — bio-physiological changes induced by exposure to the element. Satellite data were used to assess long-term changes in phytoplankton distribution and productivity. The team focused especially on chlorophyll-a levels, for which they used data 'produced by the Ocean Color Climate Change Initiative' of the European Space Agency, according to the paper. The Initiative 'integrates observations across multiple ocean colour platforms to form a continuous 26-year record'. This way, the team reported that about 39% of surface ocean iron during spring comes from atmospheric pollution, particularly in emissions from East Asia. They found this 'anthropogenic iron' has a distinct isotopic signature that makes it traceable in seawater. Its input peaked during spring, when westerly winds have been known to carry aerosols across the Pacific Ocean. The predictably higher iron concentration in spring appeared to make the phytoplankton more productive, especially that north of the Transition Zone Chlorophyll Front (TZCF) — the boundary between nutrient-rich and nutrient-poor waters. The greater access to iron enhanced the growth of the phytoplankton, which consumed more nitrates. The team wrote in its paper, 'Over the past 25 years, increasing anthropogenic iron input appears to have stimulated springtime phytoplankton growth, ultimately leading to faster depletion of … nitrate. Thus, large-scale iron pollution may be increasing the prevalence of nitrogen limitation,' expanding the size of the nutrient-poor part of the ocean. The retreat of an ecosystem boundary can have severe ecological and socioeconomic consequences. Phytoplankton are at the base of marine food chains, so a change in their distribution will affect zooplankton, fish, and larger predators like seabirds and whales. Species that can't migrate or adapt fast enough may decline or go extinct. Equally, as productive regions retreat, unproductive areas will expand and the ocean will be able to take up less biological carbon, undermining an important natural buffer against climate change. From the Science pages Question Corner Why do volcanoes erupt? Find out here Flora and fauna
Hindustan Times
a day ago
- Hindustan Times
Hurricane season begins: Are FEMA and NOAA prepared amid staffing cuts and FEMA chief's 'unaware' remark?
The Federal Emergency Management Agency (FEMA), responsible for responding to emergency situations, and the National Oceanic and Atmospheric Administration (NOAA), tasked with tracking weather conditions to predict hurricanes, have suffered dramatic cuts from the federal government at the start of the hurricane season from June 1. Concerns have risen about the lack of preparedness of these agencies to predict and tackle hurricanes in advance due to a general lack of resources. Ever since President Donald Trump took office in January, the Department of Government Efficiency (DoGE) has severely pulled back on funding given to organizations crucial in tracking and dealing with climate catastrophes along the coast. This has resulted in several staff cuts, restrictions on travel and training, and a drain of experienced professionals capable of dealing with worst-case scenarios. 'My nightmare is a major catastrophic storm hitting an area that is reeling from the impact of all of this nonsense from the Trump administration and people will die. And that could happen in Florida, that could happen in Texas, that could happen in South Carolina,' said Susan Cutter, the director of the Hazards and Vulnerability Research Institute at the University of South Carolina, in a statement to the Associated Press. Out of the 122 offices of the National Weather Service (NWS), 8 are down by more than 35% in staffing. Around 2,000 people from the full-time staff at FEMA have left the agency since Trump took office leading experts to raise concern over 'brain drain' in crucial agencies. Several emergency management training sessions have either been canceled or moved online this year. Many attendees' travel to the National Hurricane Conference was restricted this year. The launch of weather balloons, which are crucial for understanding the flow of currents and predicting storms about to hit the US, has been restricted due to lack of staffing. Former NOAA meteorologist Jeff Masters, now at Yale Climate Connections, said to the Associated Press, 'Hurricane forecasts, I'm expecting not to be as accurate this year because of that lack of balloon data.' The government has responded to such criticism by reasserting that all agencies are fully capable of dealing with any disasters and the move is meant to give individual states more responsibility in addressing local catastrophes. 'FEMA is shifting from bloated DC-centric dead weight to a lean, deployable disaster force that empowers state actors to provide relief for their citizens,' Associate FEMA Administrator Geoff Harbaugh said to the Associated Press. Only the National Hurricane Center, which is responsible for tracking developments in the Atlantic, Pacific, and Caribbean, has been spared by the administration and is running at full staff capacity. The agencies are also incorporating artificial intelligence into their tracking systems this year for more accurate predictions. No additional budgeting has been provided to states to help them deal with local disasters. Local agencies like the Mississippi Emergency Management Agency have started to take matters into their own hands. 'We have just opened our 10th, about to open our 11th DRC, Disaster Recovery Centers,' said Scott Simmons, chief communications officer for the MEMA. 'FEMA has sent just shy of 300 people to the state of Mississippi to help residents apply for what needs to be done in the wake of that storm system.' Short-term duty assignments and reassignments are being used by the NWS to fill staffing gaps. Amid rising concerns over national agencies' disaster-management capabilities, a statement made by Acting Chief of FEMA, David Richardson, has sent alarm bells ringing. Many staffers and interagency partners who attended Monday's (June 2) daily operational briefing reported Richardson expressing his unawareness about the fact that the US had a hurricane season. Though many were left puzzled by whether he meant it as a fact or joke, most people expressed that the chief genuinely seemed to be in a state of shock. The DHS tried to defend Richardson with a public statement that said, 'Despite meanspirited attempts to falsely frame a joke as policy, there is no uncertainty about what FEMA will be doing this Hurricane Season. FEMA is laser-focused on disaster response, and protecting the American people.' Richardson is a former Marine Corps officer who served overseas and was the Department of Homeland Security's (DHS) assistant secretary in dealing with weapons of mass destruction. He has no direct experience in dealing with high-stakes catastrophes. Despite these developments, representatives of the FEMA and NOAA say they are prepared to deal with any catastrophe.
Time of India
2 days ago
- Time of India
A mega tsunami could strike the US with little warning: Understanding Cascadia, the danger zones, and how to get ready
Waiting. Biding its time. The Cascadia Subduction Zone, a sleeping giant beneath the Pacific Northwest, has remained eerily quiet for over 300 years. But when it finally awakens, it won't just be a powerful earthquake that hits the coastline. A towering tsunami, land collapse, and flooding on a historic scale may soon follow. What is the Cascadia Subduction Zone? The Cascadia Subduction Zone is a massive fault line running from northern California through Oregon and Washington, and all the way to British Columbia. It's where the oceanic Juan de Fuca Plate is slowly slipping beneath the North American Plate. But the plates don't glide smoothly — they get stuck. That strain builds for centuries until it finally breaks loose in a massive earthquake. The last major quake hit on January 26, 1700. Based on geological records, it likely had a magnitude between 8.7 and 9.2. That kind of power could strike again. According to the US National Seismic Hazard Model, there's now a 15% chance of a magnitude 8.0 or greater event within the next 50 years. Areas at risk When the rupture finally happens, it won't just cause violent shaking and a deadly tsunami. According to a new study published in the Proceedings of the National Academy of Sciences, coastal land across 24 estuaries from southern Washington to northern California could suddenly sink by up to 2.67 meters (8.76 feet). As per reports, these high risk areas include Washington, Oregon, Northern California, Alaska and Hawaii. "We talk about climate-driven sea level rise, which is occurring at three to four millimetres a year, and that does eventually add up," said Prof Tina Dura, the study's lead author, in an interview with BBC Science Focus . "But here we'll have two metres of sea level rise in minutes. Why aren't we talking about that more?" That sinking, or subsidence, would permanently change the coastline. Flood zones would dramatically expand — by as much as 300 km² (115 square miles) today. Areas from southern Washington to northern California could see permanent land drops, especially in low lying estuaries. This sinking land would make flooding worse and more widespread- even long after the tsunami has receded. The Long-term fallout Beyond the quake and tsunami, recovery efforts would be hampered by the new geography. Roads and emergency services may end up underwater. Saltwater could poison farmland. Wetlands that once helped block storm surges could vanish. A 2022 FEMA planning exercise estimated 5,800 deaths from the quake and another 8,000 from the tsunami. Over 618,000 buildings, including more than 2,000 schools and 100 key facilities, could be damaged or destroyed. The total projected economic impact? $134 billion. Infrastructure now at risk includes: 5 airports 18 emergency facilities (schools, hospitals, fire stations) 8 wastewater treatment plants 1 electric substation 57 contaminant sources (gas stations, chemical plants, etc.) Aftershocks that never stop The study warns that even if the quake struck decades from now, its effects could be magnified by climate change. By 2100, global sea levels are expected to rise another 60 cm (2 feet). In Cascadia, rising land has masked some of that rise — but when the quake hits and the land sinks, the sea will seem to rise instantly. The study also estimates that if the quake happens in 2100, floodplains could triple compared to today, expanding by up to 370 km² (145 sq miles). How can people prepare themselves? There are no easy answers. Cascadia is a unique problem faced by seismologists as it is so quiet. No one can predict the exact date or time it can wreak havoc. In case of an emergency, there are a few things that residents near the coast need to remember to ensure their safety Identifying and relocating vulnerable infrastructure Educating the public on risks Prepare an emergency kit, as the infrastructure will be destroyed Practice and update your emergency plan every 6 months. Write down emergency numbers; give copies to all family members.
