Technologies

As a ‘Sea Ice Free’ Arctic Looms, the Climate Consequences Are Mounting

Research points to a milestone in the 2030s, but sea ice is already disappearing at an unprecedented rate. And that affects all of us.

The sound of ice cracking underneath the hull of a 25,500-ton icebreaker is unmistakable. No matter where you are — shuffling along the lunch line in the galley or sitting on the observation deck with a pack of cards — the wincing of steel and crunching of ice can shriek through the ship. It’s almost ghostly; undeniably haunting.

The sight of the ice? That’s mesmerizing. From the deck of Australia’s icebreaker, the RSV Nuyina, on which I sailed to Antarctica for more than five weeks at the start of 2022, it’s like looking out over a Martian landscape that’s been covered in a coat of stark white paint. In the distance, castles of ice rise from the vast, unbroken ice sheet. At the foot of one fortress, a battalion of King penguins lurks, unfazed by the freezing temperatures. Behind the ship, smaller Adelie penguins avoid a scrap with a leopard seal by climbing onto an island of ice and scurrying away.

Sea ice is vital to the Antarctic ecosystem. It’s not just a refuge for penguins and other animals, but a fundamental facet of life for creatures further down the food chain too, like Antarctic krill. It means life. The ice is also critical for heat because it’s more reflective than water, bouncing back more sunlight than the ocean, and it can act as a physical barrier, impacting the exchange of gases between the ocean and the atmosphere and protecting the continent’s ice shelves.

The Antarctic is currently experiencing the lowest level of sea ice since satellites began taking measurements in 1979. It’s an anomaly scientists are concerned about and monitoring closely. It was just a decade ago that sea ice in the Antarctic reached record highs, but generally low extents have been observed since 2016. It’s worrying, and could signal a shift in the sea ice dynamics down south, but the situation is more dire at the opposite end of the planet.

There, at the Earth’s northern extreme, the Arctic is experiencing an increase in temperatures two to four times higher than anywhere else in the world, and sea ice has decreased by about 12% per decade since the beginning of the satellite era. About 548,000 square miles of sea ice has been lost since 1979, equivalent to losing an area of ice roughly half the size of India. It’s seen a more rapid decline since 2000.

It’s one of the most obvious signs that greenhouse gas emissions are shifting the planet’s equilibrium. Researchers say we can take steps to slow the changes, but we need to act with urgency.

The 4 million people who call the Arctic home rely on the Arctic Ocean for food and transportation. The Indigenous peoples of the Arctic, who make up about 10% of the population, have a vibrant and longstanding cultural connection to the region that is slowly dripping away as regions become free of sea ice for the first time in millennia.

Meanwhile, the distribution of wildlife is shifting and behaviors are changing, altering the interactions between predators and prey. The Arctic’s famous polar bears rely on the ice to hunt and now have to travel further to eat, whereas the narwhal, a near-mythic, tusked whale, faces increased threats from killer whales lingering in exposed, warmer waters and disruptions to its migratory patterns.

Our best models currently predict the Arctic will be «sea ice free» within the next few decades, perhaps as soon as the 2030s. Antarctica’s sea ice is more of a mystery. But at both poles, sea ice is disappearing at an unprecedented rate.

And when the ice ends it’s not just the ends of the Earth that will change. It’s the entire planet.

An already changed Arctic

The Arctic Ocean’s sea ice expands during the winter, peaking in March, before retreating toward the North Pole. It typically reaches its lowest extent in mid-September. It never completely melts away — the North Pole itself is typically surrounded, and up to a fifth of the ice in the Arctic is so-called multiyear ice, persisting for more than a year.

Our understanding of this rhythmic pulse in the Northern Hemisphere stretches back for millennia. Indigenous peoples of the Arctic have passed down knowledge of the sea ice’s extent for thousands of years, particularly around coastal communities. Iceland’s government has been keeping detailed records since the 1600s, while log books and diaries kept during early exploration by ship provide a surprising amount of detail on where and when the Arctic Ocean froze over.

Our ability to understand the ice changed dramatically with the launch of the Nimbus-7 satellite in late 1978. The NASA and NOAA polar-orbiting satellite was fitted with an instrument that provided a way to observe the extent of the sea ice all year round, no matter the weather conditions, by studying the microwave energy bounced back from the surface. Continuous records have been taken since 1979, and the analysis has been deeply troubling. The extent of Arctic sea ice has been decreasing across those four decades, with each of the last 16 years the lowest on record.

Video: Changes in Arctic sea ice

Video credit: NASA’s Scientific Visualization Studio

For decades, scientists have tried to pinpoint when the total extent of Arctic sea ice will drop below 1 million square kilometers (or about 386,000 square miles) — the marker denoting a «sea ice-free» summer. In 2009, for instance, one study used climate models to determine that this mark would be hit by 2037. Other research has shown that the timing is unpredictable, with analyses suggesting we might still be decades away.

In June, a study in the journal Nature Communications analyzed 41 years of satellite data, from 1979 to 2019, reiterating that human greenhouse gas emissions are the dominant force in reduction of Arctic sea ice. It also generated a flurry of worrying headlines focused on the first ice-free summer, citing the near end of a range that it said had shifted to as early as the 2030s to 2050s. But those headlines gloss over a critical point: The current losses of summer sea ice are already having devastating effects.

«Although the first ice-free Arctic summer has constantly been a point of interest for understanding and communicating climate change, it’s more a symbolic threshold in some sense,» says Zachary Labe, a climate scientist at Princeton University and the National Oceanic and Atmospheric Administration. «Arctic climate change is already happening now and in all months of the year.»

An Antarctic paradox

From the beginning of the satellite era until 2010, Antarctic sea ice experienced a slight increase, with an acceleration in winter sea ice extent between 2012 and 2014. This was unexpected. Global temperatures have unequivocally risen in this time, largely due to human-induced climate change, raising ocean temperatures. Sea ice should’ve been melting. It didn’t.

The phenomenon was dubbed the Antarctic paradox.

Many climate models haven’t been able to reproduce these effects, though at least one high-resolution model has had success. Though explaining the paradox has been difficult, scientists have several hypotheses.

A visit to Antarctica

Natalie Robinson, a marine physicist at New Zealand’s National Institute of Water and Atmospheric Research, points out that changing wind patterns, release of freshwater from Antarctica, and ocean stratification could all have played a role over the last four decades, but she says that pointing to one variable as a driver of the increase is virtually impossible. «In reality, all of these processes act simultaneously and influence each other,» she notes.

About seven years ago, the story began to change. Antarctic sea ice extent plummeted in 2016 and hasn’t totally recovered since. In 2023, winter sea ice extent is dramatically lower than we’ve ever seen in the satellite era.

«Antarctic sea-ice extent has now adopted a downward trajectory as expected under warming and is congruent with observations of surface warming in the Southern Ocean,» says Petra Heil, a polar ice scientist with the Australian Antarctic Division. Graphs generated by Labe show the stark decline.

A line graph of Antarctic sea ice extent in 2023 generated by Zachary Labe

The record low extent has scientists concerned. Understanding the paradoxical increase over the past four decades could help unlock the reasons behind this sudden change. Does it represent a shift to a worrying new normal? Or is it merely a blip that can be attributed to the normal range of variability?

«There is certainly a fair bit of concern in the scientific community that it’s the former,» says Robinson.

«And we are racing to find out.»

When the ice ends

The great white sheets at either end of the Earth are particularly good at reflecting sunlight. Sea ice covers about 15% of the world’s oceans across the year, and up to 70% of the heating energy is reflected back into space. Cover that ice with a dusting of snow and up to 90% can be reflected.

When the sea ice disappears, the energy is absorbed by the ocean, raising its temperature. «In a positive feedback loop this ocean warming leads to even more ice loss and global warming,» says Heil. She suggests conceptualizing the impact of sea-ice loss by thinking about sea ice as the air conditioning unit of the Earth.

When the sea ice disappears, our planetary AC unit is being switched off. It becomes harder to reflect that heat into space and we lose the ability to «self-regulate» the Earth’s climate.

The change doesn’t affect just the ocean surface and the Earth’s air temperatures, though. Sea ice also plays one of the most critical roles on the planet in the ocean’s depths. As seawater freezes into ice, salt is expelled, making the surrounding water denser. This heavier, colder water sinks and gets whisked around the planet. Warmer waters are predominantly pushed by wind into the polar regions, then freeze up into ice. The cycle is known as thermohaline circulation.

«This process can be regarded as the starting point/engine of the global oceans’ overturning circulation,» says Jan Lieser, a sea ice scientist with the Australian Bureau of Meteorology and University of Tasmania.

image of the global conveyor belt with red arrows signifiying warmer water pushing around into the poles and blue arrows signifying colder deep currents

As the oceans continue to warm at both poles and sea ice extent decreases, this deep ocean current is likely to be disturbed. The knock-on effects could disrupt the polar ecosystems as nutrients and ocean biogeochemistry are altered, particularly in the Southern Ocean, where circulation is also heavily influenced by Antarctic meltwater and the currents already show signs of slowdown.

The atmosphere and ocean systems are incredibly complex and intertwined. Though the focus has long been on the extent of the sea ice, thickness also plays a role. So does snow cover. These measurements are harder to include in models because they’ve traditionally been difficult to gather. There are also differences at either pole. The Arctic typically has had thicker sea ice lasting for years, whereas Antarctic sea ice freezes new each year.

It now seems highly unlikely that the current declines can be stopped but Heil, and her colleague Melinda Webster from the University of Washington, say «it’s possible to slow and mitigate further detrimental effects of a warming climate by reducing greenhouse gas emissions and implementing ways to reduce existing atmospheric greenhouse-gas concentrations to levels that can sustain a habitable climate.»

On June 16, Heil and Webster, and more than 60 other polar scientists responded to the changes to the poles by calling for «urgent intensification of national and international research and observational capabilities in view of rapid Arctic and Antarctic change.»

«Action is required now,» she says, «to give future generations a fighting chance to mitigate the negative consequences of a warming climate.»

The anomaly in Antarctica’s sea ice this year, as if sounding its own alarm and affirming Heil’s calls, has only continued its downward trajectory.

Technologies

Today’s Wordle Hints, Answer and Help for April 19, #1765

Here are hints and the answer for today’s Wordle for April 19, No. 1,765.

Looking for the most recent Wordle answer? Click here for today’s Wordle hints, as well as our daily answers and hints for The New York Times Mini Crossword, Connections, Connections: Sports Edition and Strands puzzles.

Today’s Wordle puzzle has fairly common letters, so you might solve it right away. If you need a new starter word, check out our list of which letters show up the most in English words. If you need hints and the answer, read on.

Today’s Wordle hints

Before we show you today’s Wordle answer, we’ll give you some hints. If you don’t want a spoiler, look away now.

Wordle hint No. 1: Repeats

Today’s Wordle answer has no repeated letters.

Wordle hint No. 2: Vowels

Today’s Wordle answer has one vowel.

Wordle hint No. 3: First letter

Today’s Wordle answer begins with S.

Wordle hint No. 4: Last letter

Today’s Wordle answer ends with D.

Wordle hint No. 5: Meaning

Today’s Wordle answer can refer to maintaining an upright position on one’s feet. It’s also the main title word in a huge Stephen King novel.

TODAY’S WORDLE ANSWER

Today’s Wordle answer is STAND.

Yesterday’s Wordle answer

Yesterday’s Wordle answer, April 18, No. 1764, was TOADY.

Recent Wordle answers

April 14, No. 1760: CYCLE

April 15, No. 1761: BEGUN

April 16, No. 1762: CUBIT

April 17, No. 1763: BELLE

Technologies

Today’s NYT Connections: Sports Edition Hints and Answers for April 19, #573

Here are hints and the answers for the NYT Connections: Sports Edition puzzle No. 573 for Sunday, April 19.

Looking for the most recent regular Connections answers? Click here for today’s Connections hints, as well as our daily answers and hints for The New York Times Mini Crossword, Wordle and Strands puzzles.

Today’s Connections: Sports Edition gets a bit wild in the blue and purple categories. If you’re struggling with today’s puzzle but still want to solve it, read on for hints and the answers.

Connections: Sports Edition is published by The Athletic, the subscription-based sports journalism site owned by The Times. It doesn’t appear in the NYT Games app, but it does in The Athletic’s own app. Or you can play it for free online.

Read more: NYT Connections: Sports Edition Puzzle Comes Out of Beta

Hints for today’s Connections: Sports Edition groups

Here are four hints for the groupings in today’s Connections: Sports Edition puzzle, ranked from the easiest yellow group to the tough (and sometimes bizarre) purple group.

Yellow group hint: Play ball!

Green group hint: Gridiron roles.

Blue group hint: Like Ted Lasso.

Purple group hint: LA team that came from Brooklyn.

Answers for today’s Connections: Sports Edition groups

Yellow group: AL East teams.

Green group: First words of football positions.

Blue group: Premier League managers.

Purple group: Nicknames for the Dodgers franchise, over time.

Read more: Wordle Cheat Sheet: Here Are the Most Popular Letters Used in English Words

What are today’s Connections: Sports Edition answers?

The yellow words in today’s Connections

The theme is AL East teams. The four answers are Blue Jays, Orioles, Rays and Yankees.

The green words in today’s Connections

The theme is first words of football positions. The four answers are defensive, running, tight and wide.

The blue words in today’s Connections

The theme is Premier League managers. The four answers are Emery, Guardiola, Moyes and Slot.

The purple words in today’s Connections

The theme is nicknames for the Dodgers franchise, over time. The four answers are Bridegrooms, Dodgers, Robins and Superbas.

Technologies

Apple AirPods Max 2 vs. Sony WH-1000XM6: What’s the Best Choice for Apple Users?

How do the AirPods Max 2 stack up to Sony’s excellent WH-1000XM6 headphones? CNET’s audio expert David Carnoy gives you the full rundown.

When the AirPods Max 2 came out, I wrote an article comparing them to the original AirPods Max for Apple users who were considering upgrading. But some folks seemed more interested in my thoughts on how the Max 2 compare to Sony’s WH-1000XM6, which are among the very best noise-canceling headphones out there right now.

Both headphones earned CNET Editors’ Choice awards — and both are expensive. The AirPods Max’s high price was a source of contention when the original model launched in 2020, and the Max 2 also lists for $549. Pricing consumer headphones at more than $500 was a little shocking six years ago, but that didn’t stop people from buying the Max and setting a new benchmark for premium noise-canceling headphone prices, with top models from Bose, Sony and Bowers & Wilkins all receiving price hikes in recent years.

It’s a bit early for significant discounts on the Max 2, but later this year, they should settle in around $500 on Amazon, so you’re looking at about a $100 to $150 price bump to get them instead of the XM6, which retail for $450, but are typically discounted to around $400 in flash sales.

You can read my AirPods Max 2 review and Sony WH-1000XM6 review at those links.

Design

On the outside, anyway, the Max 2 are exactly the same as the Max USB-C, which came out in late 2024, and they’re available in the same five color options.

You can argue about which design is better and which model is more comfortable, but I’d have to give the Max 2 the advantage for pure build quality. These are headphones with a stainless steel frame, aluminum-clad earcups, smooth telescoping arms and swanky earpads that adhere magnetically and are easily replaceable. And then there’s that sweet digital crown to adjust volume and control playback.

Aside from their minimalist smart case, which I don’t love, the Max 2 have a more luxurious and durable design than the XM6. The Sonys are made primarily out of high-tech plastic and carbon-fiber composite, and their hinges aren’t immune to cracking despite their metal reinforcements, according to some user reports. The problem doesn’t seem nearly as prevalent as it was with some earlier Sony models, and I haven’t had any issues with my XM6. But online, you will find some photos of cracked or broken XM6 hinges and arms.

The trade-off for build quality is weight. The Max 2 weighs 386.2 grams or 13.6 ounces, while the XM6 weigh 254 grams or 9 ounces. The Max 2 are well-balanced and do a nice job distributing that extra weight on your head, with their breathable mesh knit canopy that spans the top of the headband. They don’t seem as heavy on your head as they feel in your hand. Most people will find both headphones quite comfortable, but you can’t get around the fact that the Max 2 are on the weightier side for headphones, and that may be a downside for some people, whether they’re on your head or in a bag, which you have to carry around with other things, such as a laptop.

It’s also not a good idea to drop the Max 2 on pavement because the aluminum can get dinged up or scratched. I’m pretty good about not dropping my headphones, but I put clear plastic earcup covers on my original Max as a precaution, especially after my daughter kept borrowing them from me. I should also note that the earpads and canopy can get a little stained and dirty if you’re not careful, especially the lighter colors. My kids don’t treat their headphones as well as I do, so I ended up having to replace the earpads for $69, though I did make my daughter pay for those replacements with her own money.

Winner: AirPods Max 2 win for build quality and durability, but the Sony WH-1000XM6 are well designed and will appeal to those looking for lighter headphones. The XM6 also have a dual-hinge design that allows them to fold up and flat (the Max 2 simply folds flat). I grade this a draw.

Features

The Max 2 have the edge in features as well, especially after Apple upgraded the Max 2 with the H2 chip, which essentially adds all the features found in the AirPods Pro 3 to the Max 2. These include Adaptive Audio, Conversation Awareness, Voice Isolation, Live Translation and Siri Interactions that allow you to use head gestures to answer and ignore calls or dismiss audio notifications. The Max 2 also support studio-quality audio recording and Apple’s camera remote feature using the digital crown. Both are useful for content creators.

The XM6 also offer a strong set of features, including Sony’s Speak-to-Chat feature, which preceded Apple’s Conversation Awareness feature. While they have different names, they both automatically lower the volume of the audio you’re listening to and shift the headphones from noise-canceling mode to transparency mode as soon as you start talking, letting you have a conversation without taking your headphones off.

But the AirPods Max 2 are designed to work with Apple products, and they automatically switch audio between devices on your iCloud account. Also, Apple’s spatial audio with head-tracking is arguably superior to Sony’s 360 Audio with head-tracking, which only works with Android devices, as Apple’s only works with Apple devices.

Now, if you’re an Android user, I’d be having a different conversation. Yeah, the AirPods Max 2 can be paired with Android devices, but they lose many of the Apple-exclusive features that set them apart. So if you’re an Android/Windows user and don’t have any Apple devices, you should opt for the XM6, which also support Sony’s high-quality LDAC audio codec if you pair them with an Android device. Or maybe Bose’s QuietComfort Ultra 2nd Gen or Bowers & Wilkins’ PX7 S3.

Winner: While the Sony WH-1000XM6 has a robust feature set available for Apple and Android devices, the AirPods Max 2 eke out a win on features for Apple users. The XM6 win for Android fans.

Noise canceling

With Apple’s H2 chip and software completely rewritten for it, both noise-canceling and voice-calling performance have improved with the Max 2. Apple says the noise canceling is 1.5x better, and you can definitely hear the difference compared to the ANC on the original Max. But the Sony XM6’s noise canceling is top-notch, and it’s hard to tell whether the XM6’s or the Max 2’s ANC is better. Ultimately, it’s very close, and both are quite impressive.

The Max 2 have a slight edge as far as their transparency mode goes. While Sony has improved its ambient sound mode that lets you hear the outside world, Apple’s transparency mode is still the gold standard, and stellar on the Max 2.

Winner: Tie

Voice-calling performance

Both have excellent voice-calling performance and do an impressive job of reducing background sound while isolating your voice. In my initial tests, I found the Sonys did a slightly better job in the noisy streets of New York, as callers said my voice sounded a little clearer and more consistent. But both headphones almost completely eliminated background noise during calls and are top-tier in the voice-calling department.

Winner: Tie

Sound quality

While both headphones sound superb for wireless headphones, they do sound different. Which one sounds better will likely depend on your personal tastes.

The Max 2 and Max 1 have a similar sound signature that’s balanced and pretty accurate. However, the Max 2’s upgraded dynamic range amplifier, coupled with Apple retuning its Adaptive EQ for the H2 chip, allows for a cleaner, more natural sound that’s nearly distortion-free.

The Max 2 do offer more clarity and dynamic sound, while the XM6 are a little warmer and more forgiving. My ears tend to gravitate toward more revealing headphones, such as the Max 2, but they can make badly recorded tracks sound even worse.

Without listening to the Max 2, you’d probably think the Sony’s sound is nicely detailed and accurate, with very good bass definition. But flipping back and forth between the two headphones, the Max 2 come across as more aggressive and intimate, while the XM6 are a little more laid back.

You can tweak the XM6’s equalizer settings in their companion app, which some people prefer. The Max 2, however, rely exclusively on their Adaptive EQ to optimize sound quality. The lack of flexible tuning bothers some people, but most don’t seem to mind the automatic tuning.

I didn’t notice that much of a change to the highs and mids between the Max 1 and Max 2. But whenever I hit a track with a harder bass line — or just more bass in general — the quality of the bass jumped out at me. Not only did it seem to hit harder, but it was tighter and more natural sounding.

The Max 2 sound a little more precise overall than the first-gen and have slightly better separation between instruments, so you can hear them a little more distinctly. That extra bit of precision helps with spatial audio, whether you’re listening to music or watching movies.

As I said, both the Max 2 and XM6 sound excellent in their own way. You can’t go wrong with either of these headphones for sound. But if you’re looking for a little more articulate headphones with slightly better clarity, the Max 2 have the edge in my book.

Winner: AirPods Max 2 win in a photo finish.

Wired listening

I’ll finish with a couple of smaller but still important items that may make a difference for some people. Note that the AirPods Max 2 have support for USB-C audio, which means you can plug the included USB-C cable into them and use them in wired mode with PCs, phones and tablets. The XM6 do not support USB-C audio.

However, the XM6 come with an analog headphone cable with a 3.5mm connector, so you can plug them into a headphone jack for wired mode (or use them with a USB-C-to-3.5mm adapter). This cable comes in handy when you need to plug into an in-flight entertainment system.

The Max 2, on the other hand, don’t include a USB-C-to-3.5mm cable for plane use, which is disappointing given their high price. You can buy the cable for around $35, but note that you have to use Apple’s official cable, not a generic USB-C-to-3.5mm cable.

Winner: The AirPods Max 2 technically have more robust wired-listening capabilities, but they get a points deduction for not including a USB-C-to-3.5mm cable, so I grade it a draw.

Battery life

Lastly, the XM6 do have the Max 2 beat on battery life. The Sonys are rated for up to 30 hours at moderate volume levels with noise canceling on, while the Max 2 are rated for up to 20 hours.

Winner: Sony WH-1000XM6

AirPods Max vs. Sony WH-1000XM6 final thoughts

Honestly, it’s hard to declare a true winner between these two great but expensive headphones. Each has some advantages and some small disadvantages.

Earlier this year, when the Max 2 hadn’t been released yet, I would have told you to get the XM6. But now that the Max 2 are here and the upgrades turn out to be a little more significant than I initially thought, it’s a tougher choice. They do offer some real advantages to Apple users from a features standpoint, so as long as you like the Max 2’s fit, they’re a pretty safe choice if you can afford them.