DALLAS (AP) — East Coast residents were jolted Friday by a 4.8-magnitude earthquake centered near Lebanon, New Jersey, with weak rumblings felt as far away as Baltimore and the Massachusetts-New Hampshire border. No life-threatening injuries or major damage have been reported.
Here’s what to know about earthquakes on the East Coast.
The Richter scale, developed by Charles F. Richter in the 1930s, is no longer widely used. According to the U.S. Geological Survey, as more seismograph stations were installed worldwide to calculate the size of an earthquake, Richter’s method was valid only for certain distance and frequency ranges.
Seismometers are instruments used to record the ground’s motion. Magnitudes are measures of an earthquake’s size. They range from 2.5 or less, which are usually not felt, to 8.0 or higher, which can cause great damage.
Earthquakes large enough to be felt by a lot of people are relatively uncommon on the East Coast. Since 1950 there have been about 20 quakes with a magnitude above 4.5, according to the United States Geological Survey. That's compared with over 1,000 on the West Coast.
That said, East Coast quakes like the one experienced Friday do happen.
“There’s a history of similar-sized earthquakes in the New York region over the last few hundred years,” said Jessica Thompson Jobe from the USGS’ Earthquake Hazards Program.
In 2011, a 5.8 magnitude earthquake near Mineral, Virginia, shook East Coast residents over a wide swath from Georgia to Maine and even southeastern Canada. The USGS called it one of the most widely felt quakes in North American history.
The quake cost $200 to $300 million in property damages, including to the Washington Monument in Washington, D.C.
The West Coast lies on a boundary where sections of Earth’s crust rub together, causing stress and slippage along fault lines that generate earthquakes relatively often.
East Coast quakes like Friday's are caused by compression over time of hard, brittle rock deep underground, according to Robert Thorson, an earth sciences professor at the University of Connecticut. “It’s like having a big block of ice in a vise and you are just slowly cranking up the vise,” he said. "Eventually, you’re going to get some crackling on it.”
These East Coast quakes can be harder to pinpoint. And they tend to affect a broader area. That’s because colder, harder East Coast rocks are better at spreading the rattling energy from an earthquake.
The distribution of cities across the East Coast also means that more people are around to experience the effects of a quake.
“We also have population centers over a large part of the northeast,” said Leslie Sonder, a geophysicist at Dartmouth College, “So a lot of people around here feel the earthquake.”
USGS experts say there is a risk of aftershocks for weeks to months, which are expected after any earthquake. They recommend paying attention to emergency messaging from local officials.
To keep safe from shakes while sleeping, remove any furniture or objects that could fall and injure you or others.
If you feel shaking, drop where you are. Cover your head and neck with one arm, crawl under a table for shelter and hold on. If there’s no shelter nearby, grasp your head and neck with both hands until the shaking stops.
AP writers John Raby in Charleston, West Virginia, and Pat Eaton-Robb in Storrs, Connecticut, contributed to this report.
The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Science and Educational Media Group. The AP is solely responsible for all content.
A display shows the news about an earthquake in New York City at News Corp Headquarters, Friday, April 5, 2024, in New York. An earthquake centered between New York and Philadelphia shook skyscrapers and suburbs across the northeastern U.S. Friday, causing no major damage but startling millions of people in an area unaccustomed to such tremors. (AP Photo/Yuki Iwamura)
FORT COLLINS, Colorado (AP) — Tick season is starting across the U.S., and experts are warning the bloodsuckers may be as plentiful as ever.
Another mild winter and other favorable factors likely means the 2024 tick population will be equal to last year or larger, some researchers say.
“It’s very bad and has only been getting worse," said Susanna Visser of the Centers for Disease Control and Prevention.
An increasing variety of ticks are pushing into new geographical areas, bringing unusual diseases. Exotic southern species like the Gulf Coast tick and the lone star tick are being detected in New York and other northern states, for example.
But the tick that experts warn of the most is a common blacklegged tick, which is found mainly in forests and spreads Lyme disease. Infection rates begin to peak in May, and U.S. health officials estimate nearly half a million Lyme disease infections happen annually.
Here's a look at what's expected this year and how you can protect yourself.
Ticks are small, eight-legged bloodsucking parasites — arachnids, not insects — that feed on animals and sometimes people. Some ticks are infected with germs that can cause illness, and they spread those germs when they bite.
There is no widely accepted estimate of how many ticks there are from one year to the next, but there is a scientific consensus that they are an increasingly common health hazard in large portions of the United States.
Blacklegged ticks — also known as deer ticks, since they feed on deer — are among the most common ticks in the eastern half of the U.S. They were plentiful centuries ago, then diminished when forests were cut down and deer were hunted, and rebounded alongside deer and wooded suburbs. The ticks have spread out from pockets in New England and the Midwest over a wider range, into the South and the Great Plains.
Tick populations cycle through the year and their numbers depend on a few factors. They like warm, humid weather, and more can be seen after a mild winter. The more deer and mice available to feed matters, too.
Overall, the blacklegged tick population has been expanding for at least four decades, researchers say.
“This is an epidemic in slow motion,” said Rebecca Eisen, a CDC research biologist and tick expert.
Weather can play a role in the severity of a tick season.
Very cold, dry winters can whittle down tick populations, but recent winters have been mild — a trend some attribute to climate change.
As Scott Williams, a tick researcher at the Connecticut Agricultural Experiment Station, said: "Winters are no longer limiting the tick population.”
Ticks can withstand the heat but tend to almost hibernate when it's a dry summer. That happened in Maine in 2020 through 2022, said Chuck Lubelczyk, a vector ecologist at the MaineHealth Institute for Research.
But last year was a very wet year, and tick activity multiplied in Maine — the state with the highest incidence of Lyme disease in the country. Weather service predictions call for higher temperatures and precipitation, so “on paper, at least, it could be a very good year for the ticks,” Lubelczyk said.
In Wisconsin, adult ticks were out longer than usual due to a mild winter. The tick nymphs are starting to emerge, and a wet spring is setting the stage for the possibility that the population will be robust, said Xia Lee, an entomologist at the Wisconsin Department of Health Services.
Ditto New York.
“It will be as bad as last year, or worse,” said Saravanan Thangamani, who studies ticks and tickborne diseases at SUNY Upstate Medical University in Syracuse.
Not all ticks are infected with disease-causing germs — about 20% to 30% of the blacklegged tick nymphs that emerge in the Northeast and Midwest this spring and into summer will be carrying the bacteria that causes Lyme disease, experts estimate.
Lyme disease symptoms tend to start between three and 30 days after a bite occurs and can include fever, headache, fatigue and a bull's-eye-like rash. If you get bitten and develop symptoms, see a doctor to get treated with antibiotics.
Experts say the best thing to do is take steps to avoid a tick bite in the first place.
If you go outdoors, make noted of wooded areas and where grassy properties start bleeding into wooded areas. Ticks tend to perch on ankle-level vegetation with their upper legs outstretched, waiting to latch on to an unsuspecting dog or human.
Try to walk in the middle of paths, wear light-colored and permethrin-treated clothing and use Environmental Protection Agency (EPA)-registered insect repellents.
When you come inside, check for ticks. They can be found anywhere on the human body, but common spots include around the waist, behind the knees, between fingers and toes, on underarms, in the belly button and around the neck or hairline.
They are harder to see when they are young, so look carefully and immediately pull them off with tweezers.
The CDC does not recommend sending individual ticks to testing services for analysis, because a person might get more than one tick bite and the results from the tested tick may not be sufficient information.
The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Science and Educational Media Group. The AP is solely responsible for all content.
Researcher Erik Foster talks in his laboratory about ticks during a tour of the Center for Disease Control laboratory Thursday, April 4, 2024, in Fort Collins, Colo. (AP Photo/David Zalubowski)
Researcher Erik Foster talks in his laboratory about ticks during a tour of the Center for Disease Control laboratory Thursday, April 4, 2024, in Fort Collins, Colo. (AP Photo/David Zalubowski)
Researcher Erik Foster talks in his laboratory about ticks during a tour of the Center for Disease Control laboratory Thursday, April 4, 2024, in Fort Collins, Colo. (AP Photo/David Zalubowski)
A tick is viewed atop a pencil eraser in the laboratory of researcher Erik Foster during a tour of the Center for Disease Control laboratory Thursday, April 4, 2024, in Fort Collins, Colo. (AP Photo/David Zalubowski)
Researcher Erik Foster uses a microscope to examine a tick in his laboratory during a tour of the Center for Disease Control laboratory Thursday, April 4, 2024, in Fort Collins, Colo. (AP Photo/David Zalubowski)
FILE - This undated photo provided by the U.S. Centers for Disease Control and Prevention shows a blacklegged tick, also known as a deer tick. Another mild winter and other favorable factors likely means the 2024 tick population will be equal to last year or larger, some researchers say. (CDC via AP, File)
