Science

That Arctic blast can feel brutally cold, but how much colder than ‘normal’ is it really?

Published

1 year ago

January 21, 2025

Daily News Staff

file 20250106 15 5zzsh1 — Philadelphia Eagles fans braved temperatures in the 20s to watch their team play the New York Giants on Jan. 5, 2025. AP Photo/Chris Szagola

Richard B. (Ricky) Rood, University of Michigan

An Arctic blast hitting the central and eastern U.S. in early January 2025 has been creating fiercely cold conditions in many places. Parts of North Dakota dipped to more than 20 degrees below zero, and people as far south as Texas woke up to temperatures in the teens. A snow and ice storm across the middle of the country added to the winter chill.

Forecasters warned that temperatures could be “10 to more than 30 degrees below normal” across much of the eastern two-thirds of the country during the first full week of the year.

But what does “normal” actually mean?

While temperature forecasts are important to help people stay safe, the comparison to “normal” can be quite misleading. That’s because what qualifies as normal in forecasts has been changing rapidly over the years as the planet warms.

Defining normal

One of the most used standards for defining a science-based “normal” is a 30-year average of temperature and precipitation. Every 10 years, the National Center for Environmental Information updates these “normals,” most recently in 2021. The current span considered “normal” is 1991-2020. Five years ago, it was 1981-2010.

But temperatures have been rising over the past century, and the trend has accelerated since about 1980. This warming is fueled by the mining and burning of fossil fuels that increase carbon dioxide and methane in the atmosphere. These greenhouse gases trap heat close to the planet’s surface, leading to increasing temperature.

Ten maps show conditions warming, particularly since the 1980s. — How U.S. temperatures considered ‘normal’ have changed over the decades. Each 30-year period is compared to the 20th-century average. NOAA Climate.gov

Because global temperatures are warming, what’s considered normal is warming, too.

So, when a 2025 cold snap is reported as the difference between the actual temperature and “normal,” it will appear to be colder and more extreme than if it were compared to an earlier 30-year average.

Thirty years is a significant portion of a human life. For people under age 40 or so, the use of the most recent averaging span might fit with what they have experienced.

But it doesn’t speak to how much the Earth has warmed.

How cold snaps today compare to the past

To see how today’s cold snaps – or today’s warming – compare to a time before global warming began to accelerate, NASA scientists use 1951-1980 as a baseline.

Get More From A Face Cleanser And Spa-like Massage

The reason becomes evident when you compare maps.

For example, January 1994 was brutally cold east of the Rocky Mountains. If we compare those 1994 temperatures to today’s “normal” – the 1991-2020 period – the U.S. looks a lot like maps of early January 2025’s temperatures: Large parts of the Midwest and eastern U.S. were more than 7 degrees Fahrenheit (4 degrees Celsius) below “normal,” and some areas were much colder.

A map shows a large cold blob over the eastern and central U.S. and Canada. — How temperatures in January 1994 compare to the 1991-2020 average, the current 30-year period used to define ‘normal,’ NASA Goddard Institute for Space Studies

But if we compare January 1994 to the 1951-1980 baseline instead, that cold spot in the eastern U.S. isn’t quite as large or extreme.

Where the temperatures in some parts of the country in January 1994 approached 14.2 F (7.9 C) colder than normal when compared to the 1991-2020 average, they only approached 12.4 F (6.9 C) colder than the 1951-1980 average.

A map shows a cold blob over the eastern and central U.S. and Canada and much-warmer-than-normal spots over Europe and the U.S. West Coast. — How temperatures in January 1994 compared to the 1951-1980 average. NASA Goddard Institute for Space Studies

As a measure of a changing climate, updating the average 30-year baseline every decade makes warming appear smaller than it is, and it makes cold snaps seem more extreme.

Charts show temperatures shifting about 4 degrees Fahrenheit when comparing the 1951-1980 average to the 1991-2020 average, considered the current 'normal.' — Charts show how temperatures have shifted in southwest Minnesota. Each histogram on the left shows 30 years of average January temperatures. Blue is the most recent 30-year period, 1991-2020; yellow is the earlier 1951-1980 period. The bell curves of the frequency of those temperatures show about a 4 F (2.2 C) shift. Omar Gates/GLISA, University of Michigan

Conditions for heavy lake-effect snow

The U.S. will continue to see cold air outbreaks in winter, but as the Arctic and the rest of the planet warm, the most frigid temperatures of the past will become less common.

That warming trend helps set up a remarkable situation in the Great Lakes that we’re seeing in January 2025: heavy lake-effect snow across a large area.

As cold Arctic air encroached from the north in January, it encountered a Great Lakes basin where the water temperature was still above 40 F (4.4 C) in many places. Ice covered less than 2% of the lakes’ surface on Jan. 4.

That cold dry air over warmer open water causes evaporation, providing moisture for lake-effect snow. Parts of New York and Ohio along the lakes saw well over a foot of snow in the span of a few days.

Maps show warm water in much of the lakes, particularly on their eastern sides on Jan. 3, 2025. — Surface temperatures in much of the Great Lakes were still warm as the cold Arctic air arrived in early January. Great Lake Environmental Research Laboratory

The accumulation of heat in the Great Lakes, observed year after year, is leading to fundamental changes in winter weather and the winter economy in the states bordering the lakes.

It’s also a reminder of the persistent and growing presence of global warming, even in the midst of a cold air outbreak.

Richard B. (Ricky) Rood, Professor Emeritus of Climate and Space Sciences and Engineering, University of Michigan

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Author

Daily News Staff
View all posts

aerospace

Boom Supersonic Update 2026: Overture Progress, XB-1 Milestones, and What’s Next

Boom Supersonic’s 2026 update: XB-1 test success, Overture production timeline, funding progress, and the challenges facing the return of commercial supersonic travel.

Published

6 days ago

April 23, 2026

Rod Washington

By STM Daily News Staff

The race to bring back commercial supersonic travel is accelerating once again, led by Boom Supersonic, a Colorado-based aerospace company aiming to succeed where Concorde left off. As of 2026, the company has achieved meaningful technical milestones—but still faces significant financial, regulatory, and industrial hurdles.

Here’s a comprehensive look at where Boom stands today, and what it means for the future of high-speed air travel.

Boom Supersonic’s 2026 update: XB-1 test success, Overture production timeline, funding progress, and the challenges facing the return of commercial supersonic travel. — Image Credit: Boom Supersonic

XB-1 Demonstrator Completes Historic Test Program

Boom’s experimental aircraft, the XB-1, has successfully completed its flight test campaign, marking a critical step toward validating the company’s supersonic technology.

Achieved multiple supersonic flights in 2025
Demonstrated aerodynamic stability and performance
Tested “boomless cruise” capabilities to reduce sonic disturbances

The XB-1 program served as a scaled demonstrator for the company’s flagship commercial jet, proving that modern materials, software, and engine integration can support efficient supersonic flight.

With testing complete, the aircraft is expected to be preserved as a prototype, representing a turning point in private-sector aerospace innovation.

Overture: Boom’s Commercial Supersonic Jet

The centerpiece of Boom’s vision is the Overture, a next-generation supersonic passenger aircraft designed to carry between 60 and 80 passengers at speeds approaching Mach 1.7.

Current projected timeline:

Prototype rollout: Targeted for 2026
First flight: Expected around 2027
Commercial service entry: Late 2020s (estimated 2029–2030)

Unlike Concorde, which catered primarily to elite travelers, Boom aims to position Overture with business-class pricing, potentially expanding access to faster global travel.

The aircraft is also being designed with sustainability in mind, including compatibility with sustainable aviation fuel (SAF).

Funding and Financial Momentum

In recent developments, Boom Supersonic secured an additional $100 million in funding, reinforcing investor confidence in the company’s long-term vision.

However, building a supersonic passenger aircraft remains one of the most capital-intensive challenges in aviation. Continued fundraising and strategic partnerships will be essential as the company moves from prototype to production.

Boomless Cruise: A Potential Game-Changer

One of Boom’s most significant innovations is its focus on “boomless cruise,” a method of flying supersonically without producing an audible sonic boom on the ground.

If proven viable at scale, this technology could influence regulatory changes—particularly in the United States, where overland supersonic flight is currently restricted.

The ability to fly faster-than-sound over land would unlock major domestic routes, dramatically reducing travel times between cities like New York and Los Angeles.

Manufacturing Challenges and Delays

Despite technical progress, Boom’s manufacturing ambitions face uncertainty. A planned production facility in North Carolina has experienced delays, raising questions about when large-scale assembly will begin.

Scaling production from prototype to commercial aircraft remains one of the most difficult phases of any aerospace program, requiring supply chain coordination, workforce development, and regulatory alignment.

Industry Skepticism Remains

While Boom has secured interest from major airlines, skepticism persists within the aviation industry.

Key concerns include:

Certification complexity and regulatory approval timelines
Operational costs versus ticket pricing
Long-term demand for supersonic travel

Even airline executives have expressed cautious optimism, with some suggesting the project’s success remains uncertain.

Boom Supersonic’s Overture: Supersonic Travel in the Making (2025 Update)

The Bigger Picture: A Defining Decade for Supersonic Travel

Boom Supersonic has moved beyond concept and into real-world testing, demonstrating that modern supersonic flight is technically achievable.

However, the next phase—bringing Overture to market—will determine whether supersonic passenger travel becomes a viable industry once again or remains an ambitious experiment.

If successful, Boom could redefine global travel times. If not, it will join a long list of bold aerospace ventures that struggled to overcome economic reality.

Sources and External Links

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/

Space and Tech

I’ve fired one of America’s most powerful lasers – here’s what a shot day looks like

A lead scientist takes you inside the Texas Petawatt at UT Austin, where hours of careful alignment and safety checks build to a single, breath-holding laser shot that briefly creates star-like conditions in a vacuum chamber.

Published

1 week ago

April 20, 2026

The Conversation

file 20260410 57 e6icf4.jpg?ixlib=rb 4.1 — Inside a laser clean room. The beam is contained within the blue pipe. Ahmed Helal

Ahmed Helal, The University of Texas at Austin

If you walk across the open yard in front of the Physics, Math and Astronomy building at the University of Texas at Austin, you’ll see a 17-story tower and a huge L-shaped building. What you won’t see is what’s underneath you. Two floors below ground, behind heavy double doors stamped with a logo that most students have never noticed, sits one of the most powerful lasers in the United States.

I was the lead laser scientist on the Texas Petawatt, or TPW as we called it, from 2020 to 2024. Texas Petawatt, which is currently closed due to funding cuts, was a government-funded research center where scientists from across the country applied for time to use specialized equipment. It was part of LaserNetUS, a Department of Energy network of high-power laser labs.

This type of laser takes a tiny pulse of light, stretches it out so it doesn’t blast optics to pieces, and amplifies it until, for a brief instant, it carries more power than the entire U.S. electrical grid. Then it compresses the pulse back to a trillionth of a second to create a star in a vacuum chamber.

On a typical shot day, the target might be a piece of metal foil thinner than a human hair, a jet of gas or a tiny plastic pellet – each designed to answer a different scientific question.

Scientists from across the country applied for time on TPW to study everything from the physics of stellar interiors and fusion energy to new approaches for cancer treatment.

Most people hear about petawatt lasers and picture something out of a movie. A “shot day” is actually hours of quiet, repetitive work followed by about 10 seconds where nobody breathes.

I now work as a research scientist at the University of Texas-Austin, studying the interaction of lasers with different materials, but a typical shot day during my time running TPW would look like this:

7 a.m.

I arrive two hours before the first scheduled shot. I put on my gown, boots and hairnet and step into the cold clean room. The laser doesn’t just turn on. You coax it awake.

I start with the oscillator, a small box that generates the first seed of light. I write down the parameters that define how the laser will behave during the shot: energy, center frequency, vacuum pressure in the tubes, cooling water level and flow. At this stage, they are fixed regardless of the experiment. The laser must perform the same way every time before the science can begin. Then I fire up the pump laser that will amplify this tiny pulse from nanojoules to about half a joule.

A diagram showing the layout of a large laser — The anatomy of a petawatt laser. A tiny pulse starts at the oscillator, gets stretched in time to avoid damaging the optics, is amplified through progressively larger stages, then is compressed back down to a trillionth of a second inside the vacuum chamber at right. Ahmed Helal, Fourni par l’auteur

The system needs at least 30 minutes to stabilize. During that time, I check alignment through every pinhole and every camera along the beam path. A slight misalignment at this stage isn’t just a problem; it can be catastrophic – a mispointed beam at full power can burn through optics that take months to source and replace, setting the entire laser back.

Building the beam

Once the system is warmed up, I send the beam into the first amplifier: a glass rod surrounded by bright flash lamps that pump light into the glass – like charging a battery. With each pass, the beam absorbs energy from the glass and grows stronger. Then the beam travels into a larger rod, where it makes four passes, picking up more energy each time until it reaches about 12 joules, roughly the energy of a ball thrown hard across a room.

This process alone takes the better part of an hour, most of it spent checking and confirming alignment and energy at each stage.

I expand the beam and send it through the final stage: the disk amplifiers. Two amplifiers, each consisting of two massive 30-centimeter glass disks, are pumped by a huge bank of flash lamps powered by capacitor banks – essentially giant batteries that store electrical energy and release it in a sudden burst. They are so large that they have their own room on a separate floor. Fast optical shutters between each stage act as gates, controlling exactly when and where the beam travels.

The shot

When the experimental team confirms that the target is in position, it asks me to prepare for a system shot. I run through the long checklist. We test the shutters and switch to system shot mode. Every monitor in the facility changes to display the same message – “System Shot Mode” – and flashes red.

A desk with 11 monitors displaying graphs. — The Texas Petawatt control room allows scientists to track a variety of parameters and metrics. On the left is the big red emergency stop button. Ahmed Helal

I lean into the microphone at the control desk, a vintage piece that looks like it belongs in a World War II radio room, and announce that we’re going into a system shot. Then I open the compressor beam dump: a heavy glass plate that normally blocks the beam from reaching the target. It takes about two minutes to move.

“Sweeping, sweeping for a system shot.”

The announcement goes out over speakers across the facility. I grab a small interlock key, put on my laser safety goggles and head downstairs. I walk a specific pattern through every room, checking that nobody is still inside. As I go, I lock each door with the key. If anyone opens one of those doors after I’ve locked them, the entire shot sequence aborts.

A microphone on a stand sitting on a desk. — Texas Petawatt scientists make announcements about the shot through a microphone in the control room. Ahmed Helal

Back in the control room, I sit down and start charging the capacitor banks. At this point, there’s no going back except for an emergency shutdown, and that means losing the shot and waiting for everything to cool down.

“Charging.”

The room goes silent. Everyone’s eyes are on the monitors. Nobody talks.

I typically will share a glance with the researcher whose project the shot is for – today it’s Joe, a visiting scientist from Los Alamos National Lab, who designed the target we’re about to vaporize. He’s gripping his coffee cup like it owes him money. I turn back to the console.

“Charge complete. Firing system shot in three, two, one. Fire.”

I press the button. A loud thud rolls through the building as all that stored energy dumps into the beam. The monitors freeze, capturing everything at the moment of the shot: beam profiles, spectra, diagnostics – these metrics provide a full picture of exactly how the laser performed and whether the shot was clean. Downstairs, in the vacuum chamber, a spot smaller than a human hair just reached temperatures measured in millions of degrees.

I lean back in my chair and start recording laser parameters as everyone exhales. A radiation safety officer heads down first to check readings around the target chamber before anyone else can enter. The experimental team follows to collect data.

Sometimes it all works perfectly. Sometimes a shutter fails to open and you lose the shot.

For example, one afternoon in 2023, we’d spent three hours preparing for a high-priority shot. Target aligned. Capacitors charged. I pressed the button and heard nothing. A shutter had failed somewhere in the chain. The monitors stayed frozen, showing black. Nobody said anything. I wrote SHOT FAILED in the logbook and started the hourlong cooldown sequence. That’s the part they don’t show in movies: sitting in silence, waiting to try again. We got the shot four hours later.

This anticipation is all part of the job: hours of patience for 10 seconds you never quite get used to. Everything happens underneath a campus where thousands of people walk above, unaware that for a fraction of a second, a tiny point of matter hotter than the surface of the Sun just existed below their feet.

Ahmed Helal, Research Scientist, The University of Texas at Austin

This article is republished from The Conversation under a Creative Commons license. Read the original article.

The science section of our news blog STM Daily News provides readers with captivating and up-to-date information on the latest scientific discoveries, breakthroughs, and innovations across various fields. We offer engaging and accessible content, ensuring that readers with different levels of scientific knowledge can stay informed. Whether it’s exploring advancements in medicine, astronomy, technology, or environmental sciences, our science section strives to shed light on the intriguing world of scientific exploration and its profound impact on our daily lives. From thought-provoking articles to informative interviews with experts in the field, STM Daily News Science offers a harmonious blend of factual reporting, analysis, and exploration, making it a go-to source for science enthusiasts and curious minds alike. https://stmdailynews.com/category/science/