The Knowledge
2025 was hotter than it should have been – 5 influences and a dirty surprise offer clues to what’s ahead
The past three years recorded unprecedented global heat, with 2025 being particularly warm. Factors such as greenhouse gas emissions and a decline in solar activity influenced temperatures and extreme weather patterns.
Michael Wysession, Washington University in St. Louis
The past three years have been the world’s hottest on record by far, with 2025 almost tied with 2023 for second place. With that energy came extreme weather, from flash flooding to powerful hurricanes and severe droughts. Yet, by most indicators, the planet should have been cooler in 2025 than it was.
So, what happened, and what does that say about the year ahead?
As an earth and environmental scientist, I study influences that affect global temperatures year to year, such as El Niño, wildfires and solar cycles. Some make Earth hotter. Some make it cooler. And one particularly unhealthy influence has been quietly hiding a large amount of global warming – until now.
Factors that made 2025 cooler than 2024
The Earth’s climate is the result of many factors that change from year to year. Some that helped make 2025 cooler than 2024 include:
La Niña’s arrival: La Niña is part of the El Niño-Southern Oscillation, a natural climate pattern that fluctuates between warm El Niño conditions and cooler La Niña conditions. During El Niño, the Pacific Ocean heats up along the equator, influencing the atmosphere in ways that can cause intense storms, droughts and heat waves around the planet. La Niña does the opposite; it’s like putting an ice pack on the atmosphere.
Both 2023 and 2024 were El Niño years, but in 2025 conditions shifted to neutral and then to La Niña starting in September.
The solar cycle: The Sun reached its solar maximum near the end of 2024, the peak of its energy output in an approximately 11-year cycle, and began declining in 2025. So, while the sun’s output was still stronger than average in 2025, it was less than in 2024.
Fewer wildfires: Despite some destructive blazes, the world also saw fewer wildfires during 2025 than 2024, which put less carbon dioxide – a planet-warming greenhouse gas – into the atmosphere.
Despite those points, 2025 still ended up as the third-hottest year in over 175 years of record-keeping and likely one of the warmest in at least several thousand years. It was nearly as warm as 2023, at 2.6 degrees Fahrenheit (1.47 Celsius) above the 1850-1900 average, according to the European Union’s Copernicus Climate Change Service. It also had the second-highest average land temperature recorded, up 3.6 F (2 C) compared to preindustrial years, with more than 10% of the land experiencing record-high temperatures.
Factors that made 2025 warmer than expected
Several other factors made 2025 warmer than expected, and some are likely to continue to increase in 2026. They include:
Greenhouse gas emissions: The big driver of global warming is excess greenhouse gas emissions, largely from burning fossil fuels, and 2025 had plenty.
Greenhouse gases trap heat near Earth’s surface like a blanket, raising the temperature. They also linger in the atmosphere for years to centuries, meaning gases released today will continue to warm the planet well into the future. The levels of carbon dioxide, methane and nitrous oxide in the atmosphere all increased in 2025.
Rising energy demand drove an increase in fossil fuel use. About 80% of the increasing electric power demand came from emerging economies, largely for rising air conditioning demands as the world gets hotter. In the U.S., the rapid growth of data centers for AI and cryptocurrency mining helped boost U.S. carbon dioxide emissions by 2.4%.
Earth’s energy imbalance: Other sources can disrupt the natural balance between the amount of sunlight that reaches Earth and the lesser amount radiated back to space. A recent study found that Earth’s energy uptake surged and temperatures rose quickly when a rare three-year La Niña in 2020-2022 shifted to El Niño in 2023-2024.
Declining polar ice, which efficiently reflects sunlight back into space, also affects the energy balance. As sea ice declines, it leaves dark ocean water that absorbs most of the sunlight that reaches it. In a spiraling feedback, warmer water melts sea ice, allowing more sunlight into the ocean, warming it faster; 2025 had the lowest winter peak of Arctic sea ice on record and the third-lowest minimum extent of Antarctic ice.
https://datawrapper.dwcdn.net/t0SSd/1
Air pollution: Sulfate aerosol pollution from coal combustion and burning heavy fuel oil in shipping has also been affecting Earth’s energy balance. It has been masking the full effects of human-caused greenhouse gases for years by reflecting sunlight back into space, creating a cooling effect. But sulfate aerosol pollution is also a serious health hazard, blamed for about 8 million human deaths per year from lung diseases.
Recent reductions in sulfate pollution – now 40% less than 20 years ago – have meant about a 0.2 F (0.13 C) increase in global temperatures. Much of the reduction was from China’s efforts to reduce its notoriously bad air pollution in recent years and international shipping rules in effect since 2020 that have reduced sulfur emissions from large ships by 85%.
Taking all factors together, humans are now warming the planet at a faster rate than at any point in human history: at about 0.5 F (0.27 C) per decade. That extra heat can fuel extreme weather, including flash floods, heat waves, extended droughts, wildfires and coastal flooding, affecting human lives and economies.
Predictions for 2026
Most climate models predict 2026 will be about as hot as 2025, depending on whether a Pacific El Niño develops, which forecasters give about a 60% chance of happening. The planet is already starting the year out warm, even if it doesn’t feel like that everywhere. While January was very cold in parts of the U.S., globally, Earth saw its fifth-warmest January on record, and much of the western U.S. saw one of its warmest winters on record.
Solar output will continue to decrease slowly in 2026. However, the International Monetary Fund projects strong global economic growth at about 3.3%, suggesting electricity demand will also continue to grow. The International Energy Agency expects global electricity demand to increase by 3.6% per year through at least 2030.
Even though global renewable energy use is growing quickly, it isn’t growing fast enough to meet rising demand, meaning more fossil fuel use in the coming years. More fossil fuels burned means more emissions and more warming, while the ability of the ocean and land to absorb carbon dioxide continues to decrease. As a result, the atmosphere and oceans heat up, increasing the risks of passing tipping points – glaciers disappear, Atlantic Ocean circulation shuts down, permafrost thaws, coral reefs die.
If greenhouse gas emissions continue at a high rate, humanity may look back at 2025 as one the coolest years globally in the rest of our lives.
Michael Wysession, Professor of Earth, Environmental, and Planetary Sciences, Washington University in St. Louis
This article is republished from The Conversation under a Creative Commons license. Read the original article.
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Science
New Glenn’s Third Mission Set for April 19 as Blue Origin Advances Commercial Space Capabilities
CAPE CANAVERAL, Fla. — Blue Origin has confirmed the launch window for the third mission of its heavy-lift New Glenn rocket, marking another step forward in the company’s expanding role in commercial spaceflight.
New Glenn’s Third Mission
Launch Details and Timeline
The mission is scheduled to lift off no earlier than Sunday, April 19, 2026, from Launch Complex 36 at Cape Canaveral Space Force Station. The two-hour launch window opens at 6:45 a.m. EDT (10:45 UTC) and closes at 8:45 a.m. EDT (12:45 UTC).
Viewers can follow the mission through a live webcast hosted by Blue Origin, beginning approximately 30 minutes before liftoff.
Mission Payload: Expanding Space-Based Connectivity
At the heart of the mission is the deployment of the BlueBird 7 satellite, developed by AST SpaceMobile. The satellite is designed to enhance a growing direct-to-smartphone broadband network, an emerging technology aimed at delivering connectivity to standard mobile devices without the need for ground-based towers.
BlueBird 7 will contribute to expanding network capacity and is expected to support initial service rollout plans targeted for 2026. The broader initiative reflects a significant shift in how satellite infrastructure could complement terrestrial telecom systems, particularly in underserved or remote regions.
Reusability Milestone: Booster Returns Again
A key feature of this mission is the planned reuse of New Glenn’s first-stage booster, “Never Tell Me The Odds.” The booster previously demonstrated a successful launch and landing during the rocket’s second mission in November, underscoring Blue Origin’s commitment to reusable rocket technology—a cornerstone of cost reduction and operational efficiency in modern spaceflight.
If successful, this mission will further validate the reliability of the New Glenn system and strengthen its competitiveness in a market increasingly shaped by reusable launch vehicles.
Industry Context: Competing in a Rapidly Evolving Market
The New Glenn program represents Blue Origin’s answer to heavy-lift launch demands, positioning the company alongside major players such as SpaceX. As satellite constellations grow in scale and ambition, reliable and cost-effective launch services have become a critical component of the global space economy.
The inclusion of commercial payloads like BlueBird 7 highlights the increasing collaboration between aerospace firms and telecommunications providers, signaling a future where space-based infrastructure plays a central role in everyday connectivity.
Looking Ahead
With its third mission, New Glenn continues to build momentum as a next-generation launch platform. The combination of reusable hardware, commercial partnerships, and advanced payload capabilities places this launch among the most closely watched developments in the 2026 spaceflight calendar.
For ongoing updates, mission tracking, and live coverage, audiences can follow Blue Origin across its digital platforms or visit its official website.
Source
Blue Origin Official Announcement – New Glenn Third Mission
Related External Links
- Learn More About Blue Origin’s New Glenn Rocket
- AST SpaceMobile – Space-Based Cellular Broadband Network
- Cape Canaveral Space Force Station Information
- NASA Overview of Low Earth Orbit (LEO) Operations
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The Knowledge
Metrolink Offers Fare-Free Rides for Earth Day 2026 Across Southern California
Metrolink offers fare-free rides for Earth Day 2026 across Southern California, encouraging sustainable travel and reduced emissions.
Metrolink Offers Fare-Free Rides for Earth Day 2026
LOS ANGELES — April 22, 2026 — In a continued push toward sustainable transportation, Metrolink will once again offer systemwide free rides on Earth Day, inviting commuters and travelers to leave their cars behind and explore a cleaner way to move across the region.
A One-Day Opportunity to Ride Free
On Wednesday, April 22, passengers can board any Metrolink train — including the Arrow service — without purchasing a ticket. The initiative is part of the broader celebration of Earth Day, encouraging environmentally conscious travel choices.
The fare-free program is designed to appeal to both regular riders and first-time users, particularly those navigating Southern California’s persistent traffic congestion and rising fuel costs.
Encouraging Sustainable Travel Habits
“Earth Day is a reminder that small changes, like choosing public transit over driving one day a week, can have a meaningful impact on our environment,” said Doug Chaffee, chair of the Metrolink Board.
With gas prices continuing to strain household budgets, the agency hopes the initiative will inspire more residents to consider rail as part of their regular commute.
Regional Connections Expand Access
Metrolink’s Earth Day promotion aligns with similar efforts by other Southern California transit providers. Riders can seamlessly connect to services operated by: LA Metro and the Orange County Transportation Authority, Riverside County Transportation Commission, San Bernardino County Transportation Authority and Ventura County Transportation Commission.
These partnerships extend the reach of fare-free travel across a six-county region, making it easier for riders to explore destinations without relying on personal vehicles.
Service Adjustments and Rider Tips
Passengers should note that trains will operate on a reduced weekday schedule, implemented earlier this spring. Despite the adjustment, all Metrolink lines and station cities remain in service.
For those planning a trip:
- No ticket is required — simply board the train
- Bikes are welcome, with capacity ranging from three bikes per standard car to nine in designated bike cars
- A curated destination guide highlights attractions within walking or biking distance of stations
Environmental and Economic Impact
Metrolink is also promoting its Personal Impact Calculator, a digital tool that allows riders to estimate how switching from driving to rail can reduce greenhouse gas emissions and lower fuel expenses.
A Broader Trend in Public Transit
Fare-free transit days have gained traction nationwide as agencies look to boost ridership and promote sustainability. Southern California’s expansive commuter rail network makes it particularly well-suited for such initiatives, offering a viable alternative to one of the country’s most car-dependent regions.
Bottom Line
Metrolink’s Earth Day promotion is more than a one-day free ride — it’s a strategic effort to shift commuter behavior, reduce environmental impact, and showcase the convenience of regional rail. For Southern Californians, April 22 presents a low-risk opportunity to rethink how they travel.
Source: Metrolink
https://metrolinktrains.com/news/metrolink-goes-fare-free-for-earth-day-on-april-22
Dive into “The Knowledge,” where curiosity meets clarity. This playlist, in collaboration with STMDailyNews.com, is designed for viewers who value historical accuracy and insightful learning. Our short videos, ranging from 30 seconds to a minute and a half, make complex subjects easy to grasp in no time. Covering everything from historical events to contemporary processes and entertainment, “The Knowledge” bridges the past with the present. In a world where information is abundant yet often misused, our series aims to guide you through the noise, preserving vital knowledge and truths that shape our lives today. Perfect for curious minds eager to discover the ‘why’ and ‘how’ of everything around us. Subscribe and join in as we explore the facts that matter. https://stmdailynews.com/the-knowledge/
astronomy for hobbyist
I found a new meteor shower, and it comes from an asteroid getting broken down by the Sun
New Meteor Shower
Across the Earth, every night, thousands of automated stargazers are waiting to take pictures of shooting stars. I am one of the scientists who study these meteors.
Most movies and news alerts focus on large asteroids that could destroy the Earth. And your phones notifies you every few months that an object nine washing machines wide is going to just narrowly skim past. However, the small dust and rubble that enter our atmosphere daily tell an equally interesting story.
My planetary science colleagues and I use camera observations of the night sky to better understand dust, car-sized asteroids and debris from comets in our solar system.
In a study published in March 2026, I searched through millions of meteor observations collected by all-sky camera networks based in Canada, Japan, California and Europe and found a small, recently formed cluster. The 282 meteors associated with this cluster tell the story of an asteroid that got a little too close to the Sun.
Meteor formation
When a sand-sized crumb of space rock hits our atmosphere, it heats up almost instantly, vaporizing its surface layer and turning it into an electrically charged gas. The whole fragment starts to glow — this is what we call a meteor. If the object is larger, like a boulder, and brighter, it’s called a bolide or a fireball. On average, these objects hit our atmosphere going over 15 miles per second. For small dust or sand-sized objects, the whole process lasts only a fraction of a second before they completely disappear.
Most of these sand-sized fragments in the solar system originate from comets – cold, icy objects from the outer reaches of the solar system. As comets pass by the Sun, their icy components turn to gas, releasing tons of dust. This is why comets are often called “dirty snowballs” and appear fuzzy in telescopic images.
Asteroids, on the other hand, are leftovers from the early solar system that formed closer to the Sun. They are dry and rocky, and do not have the same ices that give comets their characteristic tails.
What does it mean to be active?
Astronomers call an asteroid or comet “active” when it sheds dust, gas or larger fragments. This activity is caused by some external force on the object in space, like heat from the Sun, a small impact, or when asteroids spin too fast and fly apart.
Understanding and identifying activity helps scientists better understand how these objects change over time.
For comets, sublimation of ices – when solid ice turns directly into gas, skipping the liquid phase – is the primary culprit. However, for asteroids, the reason for activity can vary greatly.
For example, NASA’s OSIRIS-REx mission, which launched into space to study an asteroid named Bennu, saw activity from its surface, with heat stress and small impacts among the leading explanations.
Other sources for asteroid activity include breakup when an asteroid spins too fast, tidal forces ripping apart asteroids during close encounters with a planet, or gas release.
Researchers most commonly search for activity using telescopes. Astronomers can look for a “tail” or fuzziness around the object. This tail is a clear sign that there is gas and dust around the body. But there is another way to search for activity – meteor showers.
Finding hidden asteroids via meteor showers
The most famous active asteroid is 3200 Phaethon. It is the parent body of the Geminid meteor shower that occurs every year in mid-December. During past close approaches with the Sun, Phaethon released vast amounts of dust and larger fragments. These morsels of Phaethon have spread out along its entire orbit over time, leading to the present Geminid meteor stream.
Each meteor shower we observe occurs when the Earth passes through one of these debris streams. So if astronomers can detect meteor showers, they can also be used to find active objects in space.
At first, debris shed by an asteroid or comet travels closely together. Imagine squeezing a single drop of food dye into a moving stream of water: Initially, the dye stays in a tight, concentrated cloud. But as it flows, the water’s swirling currents pull at the dye, causing it to spread out and fade.
In space, the gravitational tugs from passing planets act like those currents. They pull on the individual meteor fragments in slightly different ways, causing the once-tight stream to gradually drift apart until it completely dilutes into the background dust of our solar system.
The discovery of a rock-comet
In a study published in March 2026 in the Astrophysical Journal, I used millions of observations of meteors to search for recent, unknown activity from asteroids near the Earth. I found one clear cluster of 282 meteors that stood out.
What makes this discovery so exciting is that we are essentially witnessing a hidden asteroid being baked to bits. This newly confirmed meteor stream follows an extreme orbit that plunges almost five times closer to the Sun than Earth does.
Based on how these meteors break apart when they hit our atmosphere, we can tell they are moderately fragile, but tougher than stuff from comets. This finding tells us that intense solar heat is literally cracking the asteroid’s surface, baking out trapped gases and causing it to crumble. This is likely a major source of past Phaethon activity and the main reason the meteorites on Earth are so diverse.
The search for the source
Why does finding a hidden, crumbling asteroid matter? Meteor observations act as a uniquely sensitive probe that lets us study objects that are completely invisible to traditional telescopes.
Beyond solving astronomical mysteries, analyzing this debris helps us understand the physical evolution of asteroids and comets in our solar system. More importantly, it reveals hidden populations of near-Earth asteroids, which is vital information for planetary defense.
The new meteor shower’s parent asteroid remains elusive. However, NASA’s NEO Surveyor mission, launching in 2027, offers a promising solution. This space telescope, dedicated to planetary defense and the discovery of dark, hazardous, Sun-approaching asteroids, will be the ideal tool for searching for the shower’s origin.
Patrick M. Shober, Postdoctoral Fellow in Planetary Sciences, NASA
This article is republished from The Conversation under a Creative Commons license. Read the original article.
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