Earthquakes and Tsunamis in the Cascadia Subduction Zone
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The Cascadia Subduction Zone lies beneath the Pacific Northwest and is where the Juan de Fuca, Explorer, and Gorda tectonic plates meet. These plates have the potential to unleash powerful earthquakes and trigger tsunamis. The Cascadia Subduction Zone runs about 700 miles long between Northern California and Northern Vancouver Island in Canada.
Researchers have predicted a large earthquake of at least 8.0 magnitude to hit the Cascadia Subduction Zone any day now. It is not guaranteed to occur soon, but sometime in the next 30 years. This would lead to extreme damages to the Pacific Northwest, causing the ground to shake for four to six minutes and tsunamis to hit the coast line in different locations shortly after.
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Understanding the potential effects of this earthquake enables communities in the Pacific Northwest to implement preparedness measures, increase resilience, and foster informed decision making by local authorities to ensure efficient allocation of resources and recovery efforts. Public awareness and education empowers individuals to take proactive steps to protect themselves and their community.
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Cascadia Subduction Zone
Vulnerability and Resilience
Those who live in urban areas, like Portland and Seattle, will be extremely vulnerable to the risks of this earthquake. The highly populated areas would heighten the risk of casualties and injuries. Healthcare facilities and emergency services will become overwhelmed due to the amount of hurt individuals who will need medical attention. Their ability to provide the necessary services will be greatly impacted.
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Vulnerability and Resilience
Specifically, Multnomah County is at great risk of life threatening levels of polluted air. Depending on the weather and time of day the earthquake occurs, it could cause deadly gases to be released that could kill thousands. Since these facility buildings were built before seismic standards for chemical storage were implemented, they have not been prepared for the damages the earthquake could cause. In order to build resilience, state lawmakers passed a bill in 2022 that requires these facilities to do seismic testing which will hopefully reduce the amount of lives the disaster could take.
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Equity
Understanding the issues with equity is important because knowing who is vulnerable and why leads to identifying and addressing the issue. The LGBTQ+ community’s specific needs are too commonly overlooked in the case of an emergency, putting them at higher risk. Sexual and gender minorities experience distinct challenges during disasters because they often lack the protective resources that cisgender men and women have readily available. In 2021, 6% of Portland's population and 5.2% of Seattle's population identified as LGBTQ+. These numbers have grown since, and at the time that was almost 300,000 people combined, not including other parts of the states.
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How to Be Prepared: Keep an Emergency Disaster Kit
This "big" earthquake is said to happen along the Pacific Northwest's Cascadia Subduction Zone. Those who do not have a plan in place for this expected disaster could be vulnerable to the effects. Having an emergency kit ready could save lives and make the aftermath of a disaster less stressful.
Preparedness
Maintaining an emergency kit is crucial in preparing for the Cascadia Subduction Zone earthquake. The kit serves as a lifeline during the critical aftermath. Supplies may be scarce or inaccessible after a disaster, so it is important to have them on hand.
These kits include items such as water, non-perishable food, and first aid supplies. Survival items such as flashlights and blankets are important, too. These items can keep families alive until help arrives.
Given the potential disruption to infrastructure and services, having a well-equipped emergency kit is a proactive measure for self-sufficiency. It will enable families to address immediate needs, give basic first aid, and endure potential challenges, like power outages. An emergency kit is an important asset in navigating the uncertainties of the Cascadia Subduction Zone earthquake and tsunami.
A Policy Brief on Financial Assistance Programs for Earthquake Recovery
One of the biggest issues in earthquake recovery is lack of finances. This is also a big issue in Portland and Seattle, where many families are low income. Many homes end up destroyed after an earthquake, as well as business buildings. This means many people lose their jobs and find themselves without an income in time of serious need. This proposed policy suggests more affordable insurance policies to encourage more people to become insured.
About 20% of Oregon's population and only about 12% of Washington's population have earthquake insurance. In the event of the big earthquake, those without insurance could possibly have to pay our of pocket costs to rebuild their home while also sheltering themselves while they rebuild. Those who do have insurance pay a lot of money and have high deductibles. Most insurance policies cost a few hundred dollars annually, which deters people from purchasing. They choose to risk paying hundreds of thousands of dollars to rebuild their home instead of paying a few hundred dollars a year to save themselves from the potential financial struggles later.
The first step to be taken to implement more affordable insurance plans is allocating some of the public budget. Consider reserving a portion of existing emergency management budgets. Allocation of funds for grants that aim to foster innovation in insurance would be the second step.
The third step would be to encourage and promote micro insurance plans. These would focus on low level income families and create more affordability for them. This could be done by organizing town hall meetings to educate low income residents about the benefits of micro insurance plans.
News Media
The news media plays a crucial role in informing the public of earthquakes and tsunamis. They have the ability to shape perceptions of these disasters. Unfortunately, this comes with challenges.
Balance
Often times, when news media is reporting on an earthquake or tsunami, they tend to address more of the short term impacts, like casualty numbers and search and rescue operations. This leaves out the long term impacts, neglecting the prolonged challenges communities face, such as rebuilding infrastructure and homes.
Timeliness
News reports are often too short to cover everything necessary. In the early stages of an earthquake, misinformation can spread too quickly. This can cause panic. The media often only covers earthquakes and tsunamis for a few hours, sometimes a few days, but rarely more.
Lack of Preparedness
The news media rarely covers the ways of how to be prepared for the next earthquake and tsunami. They focus mostly on the aftermath instead. While this would be a great time to educate the public on earthquake and tsunami preparedness, they usually do not.
Overall, the news media plays a huge role in informing the public of earthquakes and tsunamis. While that is very important, they tend to ignore the other important topics that should be mentioned. With so many people that keep up with the news, spending enough time preparing the public for long term impacts and future disasters should be standard.
Citations
What should you do before, during, and after an earthquake?. Caltech Science Exchange. (n.d.). https://scienceexchange.caltech.edu/topics/earthquakes/earthquakes-what-to-do
Be 2 weeks ready. Oregon Department of Emergency Management : Be 2 Weeks Ready : Hazards and Preparedness : State of Oregon. (n.d.). https://www.oregon.gov/oem/hazardsprep/pages/2-weeks-ready.aspx
Earthquake insurance. Division of Financial Regulation : Earthquake insurance : Storm damage : State of Oregon. (n.d.). https://dfr.oregon.gov/insure/home/storm/pages/earthquake.aspx#:~:text=About%2020%20percent%20of%20Oregonians,which%20must%20be%20purchased%20separately.
Doughton, S., & Gilbert, D. (2018, February 7). Survey finds only 11.3% of Washington Homes Have Earthquake Insurance. The Seattle Times. https://www.seattletimes.com/seattle-news/science/survey-finds-only-11-3-of-washington-homes-have-earthquake-insurance/
K. disaster relief and emergency hardship programs. (n.d.). https://www.irs.gov/pub/irs-tege/eotopick99.pdf
SBA announces major changes to its disaster lending program. U.S. Small Business Administration. (n.d.). https://www.sba.gov/article/2023/07/31/sba-announces-major-changes-its-disaster-lending-program
Earthquake insurance. Division of Financial Regulation : Earthquake insurance : Storm damage : State of Oregon. (n.d.). https://dfr.oregon.gov/insure/home/storm/pages/earthquake.aspx
Seismic risk: The biases of earthquake media coverage - copernicus.org. (n.d.-c). https://gc.copernicus.org/preprints/gc-2019-5/gc-2019-5-manuscript-version4.pdf
Jetstream Max: Cascadia subduction zone | national oceanic and ... (n.d.). https://www.noaa.gov/jetstream/tsunamis/tsunami-locations/jetstream-max-cascadia-subduction-zone
Cascadia Subduction Zone. Washington County, Oregon. (n.d.). https://www.washingtoncountyor.gov/emergency/cascadia-subduction-zone#:~:text=Impacts%20of%20a%20Cascadia%20subduction%20zone%20earthquake&text=Lastly%2C%20a%20subduction%20zone%20earthquake,tall%22%20structures%20are%20more%20vulnerable.
Ehrlich, A. (2023, October 20). Cascadia earthquake could release deadly chemicals, endangering much of Multnomah County. opb. https://www.opb.org/article/2023/10/20/report-earthquake-release-deadly-chemicals-multnomah-county/
LGBT adults in large authors: US Metropolitan Areas - Williams Institute. (n.d.-b). https://williamsinstitute.law.ucla.edu/wp-content/uploads/MSA-LGBT-Ranking-Mar-2021.pdf
Salem Statesman Journal. (2021, October 20). Be ready for a cascadia subduction zone earthquake: Build your preparedness kit in 24 weeks. Statesman Journal. https://www.statesmanjournal.com/story/news/local/earthquake/2021/10/20/earthquake-survival-kit-disaster-preparedness-go-bag-emergency-essentials/8531291002/