Nature
What’s driving re-burns across California and the West?
As climate change sparks more new fires in old burn areas, understanding the underlying causes can help shape land-management strategies
Fires scorching previously burned land are increasing at about the same rate as wildfires in the West. Understanding how to predict them provides a new tool for getting ahead of the problem.
« What’s driving re-burns across California and the West?
Newswise — LOS ALAMOS, N.M. — Seasonal temperature, moisture loss from plants and wind speed are what primarily drive fires that sweep across the same landscape multiple times, a new study reveals. These findings and others could help land managers plan more effective treatments in areas susceptible to fire, particularly in the fire-ravaged wildland-urban interfaces of California.
“Rapid climate change is the force behind these re-burns, which are increasing across the West at roughly the same rate as single-burn fires,” said Kurt Solander, a hydrologist at Los Alamos National Laboratory. Solander is corresponding author of the artificial-intelligence-based paper in the journal Environmental Research: Climate. “Predictive computer models of re-burns are thus essential to better understand their causes so that forest management practices, such as prescribed burns and forest thinning, can be updated to account for these events.”
The study defined re-burns as areas that burned multiple times over 10 to 20 years. Other factors contributing to re-burns include monthly minimum and maximum temperatures, canopy moisture levels, precipitation, runoff and more.
Re-burns threatening more of the West
Climate change is sparking more re-burns across the American West, Solander said, on a frequency comparable to single-burn fires. The study applied two forms of artificial intelligence to data about re-burns that occurred between 1984-2018 for the 11 Western U.S. states, an area of about 34,000 square miles and roughly equal to the size of Indiana. The study also analyzed data specifically from California.
To understand the role of people in these fires, the researchers zoomed in on re-burns that occurred in the wildland-urban interface. That included areas with more than 2.4 houses per square mile and covered at least 50% by wildland vegetation and areas with higher settlement densities and less than 50% wildland vegetation coverage lying within at least a mile and a half of heavily forested land.
California was the only state where the rate of increase in the number of re-burns was consistently higher in the wildland-urban interfaces across all time periods, suggesting a stronger influence there by human activity.
“Human activity is so important in California because it causes about 90% of ignitions, versus much lower levels in other areas of the West, where lightning causes more fires,” Solander said. Human activity includes everything from an out-of-control campfire to a downed power line or the hitch of a trailer dragging on pavement and causing sparks, he said.
The massive, historic Camp Fire in California in 2018 was caused by power lines and burned 153,336 acres, destroyed 18,804 structures and resulted in 85 civilian fatalities. “The fire burned across land that had experienced about a dozen fires in the previous two decades,” Solander said.
By understanding the conditions that fuel re-burns and being able to predict where they might occur, agencies responsible for wildfire mitigation can focus more of their efforts on prescribed burns and thinning and possibly come up with novel effective treatment strategies that are more resistant to re-burns in those areas, Solander said.
The paper: “The drivers and predictability of wildfire re-burns in the western United States,” Environmental Research: Climate. DOI: 10.1088/2752-5295/acb079
The funding: Information Science and Technology Institute at Los Alamos National Laboratory.
Source: Los Alamos National Laboratory
Author
News Brief
Earthquake Swarm Shakes Southern California Near Salton Sea
Earthquake Swarm: A swarm of earthquakes near California’s Salton Sea and Brawley area has prompted increased monitoring by seismologists as hundreds of tremors shake the region.
A swarm of earthquakes has been rattling Southern California near the Salton Sea, drawing attention from residents and seismologists across the region.
Salton Sea earthquake swarm?
The activity is centered near Brawley in Imperial County, an area known for frequent seismic movement due to its location within the Brawley Seismic Zone. According to the U.S. Geological Survey, hundreds of small earthquakes have been recorded over the past several days, with the strongest reaching a magnitude of approximately 4.7.
Residents throughout Imperial Valley, parts of Riverside County, and even portions of Arizona reported feeling shaking from several of the larger quakes. Minor incidents such as falling objects and brief power disruptions were also reported, though no major injuries or widespread structural damage have been confirmed at this time.
The region sits near the southern end of the San Andreas Fault and is considered one of California’s most geologically active areas. Scientists say earthquake swarms are relatively common near the Salton Sea because of the interaction between tectonic fault systems and geothermal activity beneath the surface.
While experts continue to monitor the situation closely, they emphasize that earthquake swarms do not necessarily indicate that a larger earthquake is imminent. However, officials encourage residents to review emergency preparedness plans, secure heavy furniture, and keep emergency supplies ready.
The Salton Sea region has experienced similar seismic swarms in the past, making it an important area of study for earthquake researchers and emergency management agencies.
For continued updates on this developing story and other regional news, visit STM Daily News.
Related External Links
- U.S. Geological Survey (USGS) – Earthquake Monitoring
- California Institute of Technology (Caltech)
- California Earthquake Preparedness Guide
- Ready.gov – Earthquake Safety Tips
- USGS – Salton Trough and Seismic Activity
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health and wellness
Warmer temps bring soaring tick populations – here’s how to stay safe from Lyme disease
Tick bites are rising in 2026. Learn where Lyme disease is spreading, early symptoms like the bull’s-eye rash, treatment options, and practical ways to prevent tick bites.
Lakshmi Chauhan, University of Colorado Anschutz
Spring’s warmer weather lures people outdoors – and into possible contact with ticks that spread Lyme disease.
Already, the 2026 tick season is booming. On April 23, the Centers for Disease Control and Prevention warned that emergency room visits due to tick bites are at their highest level since 2017. That may portend an especially severe season for Lyme disease and other tick-borne illnesses.
State health departments reported more than 89,000 cases of Lyme disease in 2023, the last year for which data is available. But public health experts believe that close to 500,000 people in the U.S. get Lyme disease every year.
As an infectious disease doctor with experience treating some of this infection’s long-term outcomes, I know that Lyme disease can be tricky because people often don’t notice tick bites and may overlook early symptoms of an infection. But left untreated, the infection can cause serious lingering – and even permanent – health issues.
Here’s what you need to know about Lyme disease to stay safe this season:
What causes Lyme disease?
Lyme disease, named after the Connecticut town where the disease was first identified in 1975, is caused by a group of bacteria called Borrelia – most often, the species Borrelia burgdorferi.
Deer ticks – also called black-legged ticks, and members of a group called Ixodes – transmit the disease after feeding on an infected animal, usually a bird, mouse or deer. When they then bite a person, they can transmit the bacteria into the person’s bloodstream.
Usually, the tick must attach for 24-48 hours to transmit the bacteria causing Lyme disease.
Where and when does Lyme disease occur?
Lyme disease can occur in most regions where deer ticks live.
These ticks are most active in late spring, summer and fall – usually April to November in most regions. They emerge when the temperature is above freezing. In years when winter is shorter, ticks can emerge earlier. And they may be active year-round in regions where freezing temperatures are rare.
Approximately 90% of U.S. cases are reported from states in the Northeast, mid-Atlantic from Virginia to eastern Canada, and Upper Midwest regions including Wisconsin, Michigan and Minnesota. A few cases occasionally pop up in California, Oregon and Washington.
Since 1995, the incidence of Lyme disease in the U.S. has almost doubled.
Warmer weather and changes in rainfall patterns now allow ticks to survive in new regions of the country – and for longer periods. But even in regions where ticks lived before, Lyme disease has become more common due to increases in deer populations. As woodland areas are increasingly being developed, it may be bringing the habitat of deer and mice closer to people, increasing the risk of transmission.
Lyme disease symptoms to watch for
Early symptoms of Lyme disease – fever, muscle aches and fatigue – generally emerge within three to 30 days after a tick bite. Another classic symptom in the first month is a target or bull’s eye rash at the site of tick bite, which occurs in about 70% to 80% of cases.
Other rashes following a tick bite can also occur. Some may be due to irritation from the bite, and not necessarily an infection.
If you know you’ve had a tick bite and experience flu-like symptoms – or if you see a bull’s-eye rash, whether you know you were bitten or not – it’s important to check with your healthcare provider about whether you should be treated with antibiotics.
A blood test for antibodies can help confirm the infection, but it can sometimes yield a false negative result, particularly in the first couple of weeks of the disease.
In most people, the rash goes away on its own. However, treatment may shorten its duration and is important for preventing other symptoms. A two- to four-week course of antibiotics can generally treat Lyme disease. Severe cases might require intravenous antibiotics.
A promising new vaccine for Lyme disease is currently being tested. In March 2026, Pfizer, the pharmaceutical company developing it, announced that in a late-stage study, the vaccine prevented the disease in 70% of people who received it.
Later Lyme symptoms
If left untreated, the bacteria that causes Lyme can spread, potentially causing longer-term symptoms. About 60% of people who get Lyme disease and don’t treat it can develop arthritis.
In rare cases, Lyme disease can also affect the heart and the nervous system. Inflammation in the brain or the tissues surrounding it, called meninges, can cause headaches and neck pain, as well as balance issues and memory and behavior changes. It can also cause nerve damage that results in numbness, tingling and muscle weakness.
These symptoms can appear right away or much later – sometimes months to years after infection. And in cases where the disease wasn’t promptly treated, late-stage symptoms can linger even after antibiotics kill the bacteria.
Scientists don’t fully understand why, but one intriguing study found that some particles from the bacteria’s cell wall leak into the joints and can persist after treatment, spurring ongoing inflammation and arthritis symptoms.
Another reason for Lyme’s long-term effects is that it can trigger autoimmune disease, which is when the immune system attacks its own cells. What’s more, because the nervous system may be particularly sensitive to damage caused by the bacteria and related inflammation, it may take an especially long time to heal. In some situations, the damage could be permanent.
Preventing Lyme disease
Until a vaccine becomes available, there are steps you and your family can take to help protect against Lyme disease:
- Use tick and insect repellents such as DEET and picaridin, which can be applied to skin, and permethrin, which is sprayed onto clothing, to keep ticks at bay. Treating clothing with permethrin may be especially beneficial, since the substance withstands several washes.
- Wear long-sleeve shirts and pants while you are gardening, hiking or walking through grass or woods to prevent tick bites. Wearing light-colored clothes makes ticks more visible, and tucking your pants into your socks can also prevent the little buggers from traveling from your pants, shoes and socks onto your legs.
- Remove your outdoor clothes immediately. Washing and drying clothes at high temperature can help kill any ticks that managed to hitch a ride. And a quick shower immediately after spending time outdoors can wash ticks off the skin before they have a chance to attach.
- If you spend time outdoors, perform daily tick checks, paying special attention to warm areas like your armpits, neck, ears and underwear line. If you find a tick attached, pull it off with tweezers, holding them perpendicular to the skin.
- If you find a tick that may have been on the skin for more than 36 hours, ask your healthcare provider whether a dose of preventive antibiotics – generally given within 72 hours of the bite – would be appropriate.
Lakshmi Chauhan, Associate Professor of Infectious Disease Medicine, University of Colorado Anschutz
This article is republished from The Conversation under a Creative Commons license. Read the original article.
Last Updated on April 17, 2026 by Daily News Staff
Earth Day is celebrated annually on April 22nd, and it serves as a reminder of the importance of taking care of our planet. It’s a day to reflect on our impact on the environment and to take action to create a better future for our planet.
The first Earth Day was celebrated in 1970, and it marked the beginning of the environmental movement. Since then, Earth Day has grown into an international event, with millions of people around the world participating in activities and events to raise awareness about environmental issues.
One of the main goals of Earth Day is to encourage people to take action to reduce their impact on the environment. This can include simple actions like recycling, conserving energy, and reducing waste. It can also involve more significant actions like advocating for environmental policies and supporting sustainable businesses.
Another important aspect of Earth Day is education. It’s a time to learn about environmental issues and to understand how our actions can impact the planet. Many schools and organizations use Earth Day as an opportunity to teach children about the importance of taking care of the environment.
This year’s Earth Day theme is “Restore Our Earth”, and it focuses on the idea that we can all play a role in restoring the planet’s ecosystems. This can include actions like planting trees, reducing plastic waste, and supporting sustainable agriculture.
Earth Day is an important reminder of the impact that we have on the environment and the importance of taking action to create a better future for our planet. By working together and taking small steps, we can make a big difference in protecting the planet and ensuring that it remains healthy and beautiful for generations to come.
Earth Day – April 22
https://nationaltoday.com/earth-day/
https://stmdailynews.com/category/science/
