California experiences a variety of devastating disasters, including earthquakes, and the California Governor’s Office of Emergency Services (Cal OES) encourages all Californians to take proactive steps to be prepared before, during and after earthquakes through Earthquake Warning California.  

Cal OES will be kicking off its Annual California Great ShakeOut Tour beginning October 14, 2024 starting in San Diego. Cal OES invites the public to attend any one of three different locations throughout the state to catch a ride on the shake trailer which simulates the intensity of up to a 7.0 magnitude earthquake. The tour includes stops in the following counties: San Diego, Los Angeles, Sacramento and join us in practicing drop, cover and hold on, statewide on October 17 at 10:17 a.m. 

At each event location, not only will Californians be able to experience a simulated earthquake but will be able to engage with subject matter experts as they share information about Earthquake Early Warning technology, preparedness tips and recommend life-saving actions like drop, cover, and hold on. 

On October 17, Cal OES encourages all Californians to take part in the Great ShakeOut Drill at 10:17 a.m. (PST) and join countless others as they demonstrate the correct technique of drop, cover and hold on. 

Cal OES has compiled a toolkit for media outlets and partners to use and be the voice in their communities. This toolkit is complete with examples of copy to use for social media, graphics, and more. Have more questions? Reach out to media@caloes.ca.gov  

Access our full partnership toolkit. 

Cal OES serves as the state’s lead emergency management agency, including responding, directing, and coordinating state and federal resources and mutual aid assets across all regions to support communities across the state.  

As California continues to harness the power of science and technology to help keep our communities safe, when it comes to earthquakes, seconds can save lives. Cal OES is home to Earthquake Warning California and the state’s earthquake warning system.

The earthquake early warning is an intricate system that uses the latest technology, including smartphone applications, operating system features and Wireless Emergency Alerts (WEA), to provide individuals with an earthquake warning as soon as shaking is detected by ground motion monitoring in California. 

Californians can be proactive in their own readiness by learning about Earthquake Warning California, which provides preparedness tips, actions to take during shaking, and how to recover after shaking stops all available at earthquake.ca.gov.

Recently, California communities across the state have been experiencing minor earthquakes, which is a good reminder for everyone to be prepared when shaking starts. In just the past few weeks, Californians have experienced a handful of earthquakes in Ojai, Salinas, Morgan Hill, Ferndale and San Diego, to name a few. 

Continuing to lead the country in disaster resiliency, the California Governor’s Office of Emergency Services (Cal OES) is also home to Earthquake Warning California. Using state-of-the-art technology, Cal OES’ Earthquake Warning California has alerts and resources available so that individuals and families are prepared for the next big quake. 

That’s why knowing what to do if an earthquake hits our community is essential because it’s not if but when it happens. 

PREPAREDNESS TIPS 

• Sign up for life-saving alerts through Earthquake Warning California 
• Know how to protect yourself during an earthquake 
• Drop to the ground, cover your head with your arms, and hold onto your neck until shaking stops 
• Develop an emergency preparedness plan 
• Create a customized emergency plan for your specific needs 
• Pack an emergency supply kit 
• Your emergency kit should address all daily needs 
• Understand and mitigate hazards 
• Visit myhazards.caloes.ca.gov to learn about local risks and how to prepare your home (including securing furniture, appliances, home fuel systems and more) 

RECEIVE ALERTS 

To receive earthquake warnings, there are three ways for individuals and families to get alerts through the California Earthquake Early Warning System. 

• MyShake App: Free smartphone app that provides iPhone users with audio and visual warnings, available in six different languages. 
• Android Earthquake Alerts: Android phones with updated operating systems are automatically subscribed to Android Earthquake Alerts, which uses the same technology as the MyShake App; and 
• Wireless Emergency Alerts (WEAs): No-cost text messages for emergency situations sent through the nation-wide system providing lifesaving information for the State of California 

LEARN MORE 

Join your neighbors in being prepared and aware of what to do when the next big earthquake occurs. 

For more earthquake preparedness tips, visit earthquake.ca.gov. 

As the state’s premier emergency management agency, the California Governor’s Office of Emergency Services (Cal OES) continues to monitor all disasters around the clock, including earthquakes. 

Beginning in February 2024, earthquake swarms in the Southern California area have occurred in four distinct areas in the vicinity of the Salton Sea:  

• El Centro 
• In the Brawley area 
• The Cerro Prieto geothermal field in Baja, Mexico 

These areas are located on the active tectonic boundary between the North American and Pacific Plates. The separate areas of activity represent the complexity of the plate boundary in this area and the interaction of geothermal fluids with faults in the earth. 

WHAT IS AN EARTHQUAKE SWARM? 

A swarm is a made up of a series of mostly “smaller” earthquakes with no identifiable mainshock. Swarms are typically short-lived, but they can continue for days, weeks, or sometimes even months. They often occur in the same location as previous swarms. While the mechanisms are not thoroughly understood, a swarm can be associated with geothermal activity. The landscape in and around El Centro, for example, is one of the more active geothermal areas in the state. 

Geothermal activity is typically associated with effects from heat in the earth. Active tectonics can cause thinning of the earth’s crust, making it hot and heating fluids beneath the surface. Magma in the earth can also heat underground fluids. Both conditions exist in the Salton Sea region. Earthquake swarms can be caused by these pressurized, hot fluids moving beneath the earth’s surface, increasing stress on faults within the earth and causing earthquakes. 

WHAT IS EARTHQUAKE SEQUENCE? 

An earthquake sequence is characterized as a “mainshock” earthquake followed by one or more smaller “aftershocks.” Typically, the mainshock is an earthquake with a magnitude about one level larger than the aftershocks or foreshocks. They occur near the fault zone where the mainshock occurred and are considered part of the “readjustment process” after the main slip on the fault. Aftershocks become less frequent and smaller in magnitude over time, although they can continue for days, weeks, months or even years after the initial, larger mainshock.  

EARTHQUAKE PREPAREDNESS 

While knowing the difference between earthquake swarms and sequences can be essential to knowing the risks, Cal OES continues to prepare Californians for the possibility of major shaking and additional impacts to communities from earthquakes. Everyone can take proactive steps to be prepared for the next big earthquake, because when shaking starts, seconds matter.  

• Download the “MyShake” app and turn on wireless emergency alerts notifications on your mobile device. 
• Practice life-saving actions like: “Drop, Cover and Hold On.” Or, for those who utilize mobility assistance devices, “Lock, Cover and Hold On.” 
• Create a Go-Bag with essential items like important documents, flashlights, extra clothing, first aid kit and more. 
• Secure household items: Fasten free standing televisions, secure bookshelves to walls and secure smaller items that can break or fall during shaking.  
• Create a Stay-Box with enough essential items to sustain your family for at least two weeks, as you may be required to shelter in place. 

For more tips and resources go to http://www.earthquake.ca.gov. 

Earthquakes are natural disasters that have fascinated and terrified humans for centuries. These powerful geological events can cause significant destruction and loss of life, which has led to the emergence of numerous myths and misconceptions over time.  

The California Governor’s Office of Emergency Services (Cal OES) continues to raise awareness for earthquake preparedness and education, and build resiliency so Californians are better prepared for, can respond to and recover from the destruction of earthquakes.  

However, there are still many common earthquake misconceptions that persist.  

Myth #1: Earthquakes Only Happen in Certain Parts of the World 

FALSE: One of the most common myths about earthquakes is that they only occur in specific regions of California. 

In reality, earthquakes can happen almost anywhere in the world. Earth’s crust is divided into tectonic plates, and movement can occur along the boundaries of these plates or within them. This means that regions far from plate boundaries, like the central United States, can experience earthquakes. It’s essential to recognize that no area is entirely immune to seismic activity. In California, the most notable fault is the San Andreas fault. In realty, several faults exist and can cause shaking anywhere. Depending on the size, shaking can be felt miles from the initial epicenter.  

Learn more about hazards in your area. 

Myth #2: Earthquakes Can Be Predicted with Precision 

FALSE: Many people believe that scientists can predict earthquakes with pinpoint accuracy, providing specific dates and times for when they will occur. Another common myth is that new technology exists to predict earthquakes. And finally, a popular myth is that animals can predict them.  

Unfortunately, earthquake prediction remains an extremely challenging endeavor. While scientists can monitor fault lines and detect patterns of seismic activity, they cannot predict exact earthquakes reliably. Instead, they focus on forecasting the probability of earthquakes over long periods, which helps with preparedness but does not provide precise predictions.  

Cal OES continues to encourage Californians to learn about the Earthquake Early Warning system which quickly detects an earthquake through seismic sensors to distribute notifications to your mobile device for extra time to take protective action like drop, cover and hold on through the MyShake App, local Wireless Emergency Alerts and local county or city alerts. The system also implements safety measures to public utilities like, slowing commuter trains down and opening bay doors at fire stations. However, the technology is NOT predictive. The further away you are from the earthquake epicenter, the more likely you are to receive an alert BEFORE shaking is felt.  

Myth #3: You Should Stand in a Doorway During an Earthquake 

FALSE: In the past, doorways were considered one of the strongest parts of a building’s structure, leading to the idea that they may offer greater protection from earthquakes. Experts have widely debunked the myth that standing in a doorway is the safest place to ride out an earthquake. Modern building codes and construction have significantly improved the structural integrity of all parts of buildings, meaning that doorways are no safer than other areas. 

The most important earthquake safety tip we can share is to simply “Drop, Cover, and Hold On” during an earthquake. This is the best way to protect yourself from hazards, such as objects that may fall off shelves and heavy items that may tumble down during earthquake shaking. 

Myth #4: Earthquake Weather Exists 

FALSE: Many cultures have long-held beliefs that certain weather conditions can predict earthquakes. Common signs include hot, dry or windy weather preceding an earthquake.  

There is no scientific evidence to support these claims. Earthquakes are caused by the movement of tectonic plates beneath the Earth’s surface, and weather patterns are not reliable indicators of impending seismic activity. 

Myth #5: Small Earthquakes Relieve Pressure and Prevent Larger Ones 

FALSE: It’s a common misconception that small earthquakes can release pressure along fault lines and prevent more significant earthquakes.  

While small earthquakes can indeed relieve some stress along a fault, they typically DO NOT significantly affect the likelihood of larger earthquakes. In fact, a sequence of smaller quakes can SOMETIMES indicate that a larger one is on the horizon, but not always. It’s essential to remember that earthquakes are unpredictable and can happen at any time or anywhere. Cal OES continues to focus on earthquake preparedness, response and recovery to build resiliency in communities statewide. 

Myth #6: Aftershocks are Always Less Destructive than the Initial Earthquake 

FALSE: A common myth is that aftershocks are less destructive than the primary seismic event.  

While most aftershocks may be smaller than the initial shaking, they are no less destructive than the first impact. For example, the 1994 Northridge earthquake was recorded at a 6.7 magnitude but had aftershocks of up 6.0 which caused additional damage to structures weakened by the initial impact. A similar misconception is that aftershocks occur directly after initial shaking, when they can occur weeks to months after. In 2022, the Ferndale earthquake struck in Humboldt County. A 5.4 magnitude aftershock occurred a couple of weeks later that also caused infrastructure damage to the surrounding areas.  

Plan, Prepare, Respond and Recover 

Understanding the truth about earthquakes is crucial for personal safety and preparedness. While these common earthquake myths may persist, it’s essential to rely on scientific knowledge and established earthquake safety guidelines. Also, by dispelling these myths and focusing on accurate information, individuals can better protect themselves and their communities during seismic events. Earthquakes are natural yet unpredictable. Cal OES continues to encourage all Californians to be prepared for, respond to and recover from earthquakes.  

When shaking starts:  

• Drop, Cover, and Hold On.  
• After the ground stops shaking, follow your evacuation plan.  
• And don’t forget to grab your earthquake preparedness kit, including a go-bag, on your way out the door. 

Learn More: Earthquake.ca.gov 

California is known for its diverse and stunning landscapes, and it’s also known for its variety of natural disasters like earthquakes.  

Have you ever felt the ground shake during an earthquake? When there is an earthquake, different kinds of waves are produced, and these waves shake the ground at different times. These include the fast-moving waves, known as P-waves, followed by slower moving, more damaging waves called S-waves. 

The California Earthquake Early Warning System powered by ShakeAlert, uses seismic sensors to quickly detect these waves caused by earthquakes, estimates the magnitude of the shaking and determines when to activate emergency alerts on phones.  

But what’s the difference between a P-Wave and an S-Wave? 

P-Waves: The Fast Movers 

P-waves, or Primary waves, are the first waves to arrive as soon as there’s an earthquake. They move very fast, about 3.7 miles per second. You may or may not feel these waves, but they are recorded by seismic sensors.    

S-Waves: The Slow Movers  

S-waves, or Secondary waves, are the next waves to arrive after P-waves. They move slower, about 2.5 miles per second. These waves, are the high intensity shaking that we feel and are the more damaging waves that earthquakes produce.  

How The Waves Help The Earthquake Early Warning System 

With over a thousand seismic sensors built across the state to detect earthquakes, Cal OES along with federal, state, and local partners developed the California Earthquake Early Warning System. This system detects the P-waves and immediately transmits data to a ShakeAlert processing center, where the location and size of the quake are estimated and updated as more data becomes available. If the magnitude meets the threshold of M4.5 or higher, automated actions are taken, including alerts to cell phones, slowing trains down and opening first responder bay doors.  

Cal OES along with other federal, state, and local partners continues to maintain and advance the technology of the system to increase advance warning of intense shaking for all Californians.  

So next time you hear about an earthquake, remember: P-waves are the speedy ones that help California’s Earthquake Early Warning System, and S-waves are the slower, but more intense shaking we feel.  

PREPAREDNESS TIPS  

• Sign up for life-saving alerts through Earthquake Warning California  

• Practice life-saving actions like, drop, cover and hold on  

• Develop an emergency preparedness plan  

• Pack an emergency supply kit  

• Understand and mitigate hazards: Visit myhazards.caloes.ca.gov to learn about local risks and how to prepare your home (including securing furniture, appliances, home fuel systems and more) 

Anchored at the Governor’s Office of Emergency Services (Cal OES) since 2019, Listos California has succeeded in reaching millions of Californians who otherwise wouldn’t have access to lifesaving emergency preparedness information. Providing tools to help vulnerable Californians not only survive, but also thrive post-disaster, is what makes Listos California so vital.

For a complete list of virtual resources, go to ListosCalifornia.org 

• Listos California Social Toolkit
• Listos California Stay Safe Flyer
• Listos California Quick Guide
• Listos California Disaster Ready Guide