2023年平安夜前夕的南半球，夏日陽光穿過灰色雲層灑落在冰面上。美國破冰船“納塔尼爾·帕爾默”（Nathaniel B. Palmer）號被無邊無際的厚冰層包圍著，幾個小時前，這艘私有破冰船撞上了固定冰（fast ice）——附著於海岸線、不隨風和洋流漂移的海冰。船上的研究人員走下舷梯來到冰面上，他們須要花幾個小時採集海冰樣本，以瞭解海冰融化對海洋化學、海洋物理以及地球氣候的影響。
進行了一個多小時的取樣工作後，他們看到幾千米外的船後面有一排黑點，這些黑點正快速朝他們移動。很快，研究人員意識到那是一群阿德利企鵝（Pygoscelis adeliae），南極最小的企鵝物種。它們排成一條長隊穿過冰面——有的在笨拙地行走，有的則用腹部滑行，數量大約 100 只。
它們繞著船走來，直奔研究人員取樣的地方。它們離研究人員很近，如果允許的話，研究人員甚至可以摸到它們。研究人員別無選擇，只能停下工作，欣賞這些大膽地繞著他們的裝置走動的好奇崽崽。
企鵝們嘎嘎叫著，揮動著翅膀，檢查著冰面上每一個用機器鑽出的洞。它們對鏟子特別感興趣，有些企鵝看起來甚至想和這些工具“發生關係”，還有一隻跳進了科學家用來攜帶裝置的塑膠滑道，就是不肯離開。
美國阿拉斯加大學費爾班克斯分校（University of Alaska Fairbanks）的化學海洋學家勞拉·惠特莫爾說（Laura Whitmore）說：“我們不應該干涉企鵝，對吧？所以如果它們來了，我們只能讓它們待在那兒。”惠特莫爾是“帕爾默”號冰層作業的負責人，她的同事給她起了個綽號叫“冰雪女王”。
惠特莫爾表示，她寧願企鵝別出現在他們的取樣區，因為研究人員須要獲取乾淨的樣本，而企鵝……很髒。這是惠特莫爾第一次來南極洲，她通常在北極研究海冰，那裡沒有企鵝，她對這些鳥類的好奇心感到驚訝不已：“我們第一次登上冰面，它們就直接向我們游過來，它們靠近人類的行為是第一件令我驚訝的事。然後，這一幕再次上演，就好像這就是它們會有的行為，它們就是會向我們游過來。”
在冰上取樣對體力要求很高，部分原因是在冰面上行走非常困難，尤其是穿著三層厚衣服。研究人員會不停陷入雪裡，也會各種摔倒。尋找冰塊進行取樣的整個過程也很艱難。每次研究人員離開船時都很容易被企鵝找到，但對於人類來說，找到合適的海冰要困難得多。
厚厚的浮冰經常包圍著破冰船，成千上萬的浮冰像一塊不連貫拼圖的巨大碎片，散佈在海面上。隨著船的移動，沉重的巨大浮冰撞擊著船體，發出雷鳴般的響聲。
研究人員需要找到一塊足夠堅固的浮冰，以便能夠支撐他們踩上去，但又不能太厚，太厚的話用來在浮冰周圍航行的小型充氣船可能會夠不到浮冰頂部；浮冰還必須處在不會被風吹向船體、船上的煙霧也不會被吹入冰層汙染樣本的位置。
另一個難題是亮度。即使浮冰不是平的，它反射的光線也可能讓它看起來是平的，你很難看出上面是否有突起、裂縫或不平坦的地方。
每次尋找浮冰時，惠特莫爾和船上的海洋技術人員都要在艦橋上花六個小時透過窗戶尋找一塊合適的海冰，用雙筒望遠鏡和十足的耐心。希瑟·傑克遜（Heather Jackson）是美國南極洲計劃（U.S. Antarctic Program）的海洋技術員，她的工作是幫助“帕爾默”號上的研究人員找到一塊好浮冰，並在他們登上冰面後保證他們的安全。
當尋覓找到一塊合適的候選浮冰時，研究人員會穿上覆蓋全身的橙色救生衣，這是一種足夠厚的救生衣，可以抵禦嚴寒，也能在水中幫助研究人員浮起來。然後，他們會用掛在船體側面的繩梯（Jacob’s ladder）從“帕爾默”號上下來，跳進小型充氣摩托艇，靠近候選浮冰進行初步檢查。摩托艇會繞著浮冰行駛，以便研究人員檢查浮冰是否穩固，然後找到一個有希望的位置時，駕駛員會將摩托艇慢慢開到冰上。
冰面上的往往覆蓋著雪，這些雪有時過於鬆軟，讓人難以在上面行走，有時掩藏著一層不穩定的、泥濘的冰。海洋技術員會用一根長長的金屬棍在冰面上四處戳一戳，確保它的穩固性。
確定好穩固性後，研究人員就把他們的重型裝置搬到冰上，包括管道、鏟子、水桶，以及每個人都有的個人防水袋。防水袋裡裝有食物、水、額外的冬裝和一個用來排尿的瓶子，以備不時之需，畢竟他們會在冰上待上六個小時。
Penguins and Ice Samples Make This Research Vessel Paradice
Rachel Feltman: For Scientific American’s Science Quickly, this is Rachel Feltman. You’re listening to part two of our Friday Fascination miniseries all about Antarctica.
Last week we met award-winning Brazilian journalist Sofia Moutinho onboard a U.S. icebreaker called the Nathaniel B. Palmer. Today we’ll follow her as she and her fellow passengers hit the ice—literally disembarking onto one of the many ice floes that drift through the Southern Ocean. They’ll have to navigate tricky terrain and frigid temperatures to collect samples of pristine ice, which is crucial for helping scientists figure out how the world’s waterways will change as our warming climate melts this region’s glaciers and ice shelves.
But before we get into all that science—and the hard work that makes it possible—Sofia has some new friends to introduce us to.
Tara Williams: It’s bowing [laughs]!
Kouba: It’s just so much gratitude. It’s just—it’s once in a lifetime, these things. I just—oh, my God [cries louder]!
Sofia Moutinho (tape): Are you crying?
Kouba: I just—I’m absolutely crying!
Moutinho (tape): You cried, too, right?
Williams: Yes, a few times [cries and laughs at the same time]. It’s just beautiful and amazing, and who gets to see this?
Moutinho: It’s the night before Christmas Eve in 2023. The austral summer sun shines behind gray clouds. An endless, thick layer of ice surrounds the Nathaniel B. Palmer, a U.S. icebreaker. It has only been a few hours since our ship rammed into the fast ice so we could disembark. Fast ice is the technical term for this frozen seawater connected to the shoreline.
Our gangway is down, and a group of researchers is out on the ice. They will spend hours outside sampling sea ice to understand how its melting is affecting the chemistry and physics of the ocean as well as Earth’s climate.
But with hard work comes feathered rewards.
You just heard the researchers crying with joy after an unexpected encounter with local wildlife.
Williams: I don’t even have words.
Teagan Bellitto: I’m so happy they came over.
Williams: My face hurts from smiling so much.
Moutinho: “They” were Adélie penguins, the smallest penguin species in the Antarctic.
The researchers had been sampling for a little more than an hour, collecting snow from the surface and drilling ice cores with noisy machines, when we saw a line of black dots a few miles away, behind the ship. The shapes were moving quickly toward us.
Ken Block: There are a lot of penguins over there!
Moutinho (tape): Yes, there’s, like, 100 penguins coming this way!
Moutinho: Soon enough we realized it was a group of Adélies. They moved across the ice in a huge line—some walking clumsily, others sliding on their belly.
Laura Whitmore: Oh, my gosh!
Moutinho (tape): Did you see that? There’s like 100 of them!
Whitmore: The penguins are coming! Oh, my gosh!
Other researchers: Oh, my gosh!
Moutinho (tape): It’s the March of the Penguins!
Moutinho: They went around the ship and straight to the spot where the researchers were sampling. They were so close to us that we could touch them if we were allowed to. The scientists had no choice but to stop their work and admire the visitors, who boldly walked all around their equipment.
[CLIP: Penguins make noise while researchers look on and take photographs]
Moutinho: The gang of penguins squawked, honked, waved their wings and inspected every hole on the ice. The animals had a special admiration for the scientists’ shovels. Some looked like they wanted to mate with the tools. One of them jumped into a plastic slide that the scientists use to carry equipment and just wouldn’t leave it.
[CLIP: Penguin noises]
Whitmore: We’re not supposed to interfere with the penguins, right? So if they come, we kind of have to just let them be there.
Moutinho: That’s Laura Whitmore, a chemical oceanographer at the University of Alaska Fairbanks and leader of ice operations on the Palmer. Because of that her colleagues nicknamed her “the Ice Queen.”
Whitmore: While we’re doing the work, I would rather them not be right in our sampling area. We’re trying to get clean samples, and penguins are pretty dirty [laughs].
Moutinho: While we had never seen so many penguins on the ice before, this was not our only encounter with them. These birds greeted us practically every time we stopped to collect samples during our journey in West Antarctica.
This was Laura’s first trip to Antarctica. She usually studies ice in the Arctic, where there are no penguins, and she was surprised by how curious these birds are.
Whitmore: The first floe we were on, they came right up to us, and I just think their behavior—coming close to people—was the first surprising thing. And then they did it again. It’s like, “This is just their behavior. They’re going to come up to us.”
Moutinho: Just before our penguin encounter, I asked Laura about her expectations for our time on the ice that night. She couldn’t have known what was about to happen, but what she said proved prophetic.
Whitmore: I have a friend who always says, “Another day on the ice is another day in paradise,” which is pretty true.
Moutinho: But even in this icy paradise, it’s easy to break a sweat. Sampling on ice is physically demanding, in part because it’s super hard to walk across the surface, especially wearing three layers of thick clothes. I kept sinking into the snow and falling down. So did the scientists.
Bellitto: I fell in a nice little snow patch there—like, a deep hole—on my way here. And I was like, “You know, I thought I was going to be so graceful.”
Whitmore: You thought that?
Bellitto: Yeah, I like to be optimistic.
Moutinho: The whole process of finding ice to sample is also hard.
While it was easy for the penguins to find us on the ice every time we left the ship, finding the right sea ice was much more difficult for the humans.
Thick ice floes often surrounded the ship. Thousands of them were spread across the ocean surface like gigantic pieces of an incoherent puzzle. As the ship moved, their huge masses hit the hull, making thunderlike sounds.
[CLIP: Ice floes knock against the hull of the ship]
Moutinho: The researchers needed to find an ice floe that was sturdy enough for us to step on but not so thick that the top was out of reach from the small inflatable boat we used to navigate around the floating ice. The floe also had to be positioned in a spot where the wind would not blow it against the hull or throw the ship’s smoke into the ice, contaminating the samples.
The brightness was another challenge. Light reflecting off ice floes makes them look flat, even if they aren’t. It was difficult to see if there were ridges, cracks or areas of uneven ground.
Every time we went on an ice hunt, Laura and the marine technicians onboard spent up to six hours on the bridge looking through the big windows for a good piece of sea ice. They were armed with binoculars and patience.
[CLIP: Background music]
Whitmore: We’re just going to kind of keep on going to the next bits of ice and keep looking.
Heather Jackson: To find a better favorite.
Moutinho (tape): Window-shopping for ice.
Whitmore: Yeah [laughs], literally, through the windows.
[CLIP: Jackson hums the music playing on the bridge]
Moutinho: Heather Jackson is the person humming with Laura. She is a marine technician with the U.S. Antarctic Program. Her job is to help the researchers onboard the Palmer find a good piece of ice and keep them safe once they land on it.
Jackson: Sea-ice work is a slow process, and it moves at a glacial pace sometimes.
Moutinho: Heather, Laura and another marine technician, Stuart Siddons, often had long discussions before choosing which ice floe to inspect more closely.
Stuart Siddons: That one’s a good option.
Whitmore: Okay.
Moutinho: When the researchers found a good candidate, they put on orange flotation suits that covered their whole body. The suits are thick enough to protect against the cold and will float if someone falls in the water.
Then we went down from the Palmer using a Jacob’s ladder—a rustic ladder made out of ropes and planks—hanging on the side of the hull.
Siddons: Okay, come on down!
Henry Thoreen: You’re the next contestant. Two more steps. One—okay.
[CLIP: Something hits the floor of a boat]
Moutinho: We jumped into a Zodiac, a small inflatable motorboat.
Siddons (on the radio): Bridge, bridge, Zodiac Two away at nine.
Whitmore: To good science!
Technician (on the radio): Roger that, Zodiac Two away at nine.
[CLIP: The boat’s motor revs, and waves splash]
Mollie Passacantando: This is awesome!
Moutinho: Sitting on the edge of the boat, we approached the candidate ice floe for an initial inspection. We drove around the floe while the researchers checked if the ice was stable. When the team found a promising spot, the pilot inched the Zodiac up onto the ice.
[CLIP: The boat’s motor stops, and waves splash]
Siddons: I’m thinking it’ll sluff a little bit, but I can get my nose up pretty far.
[CLIP: The boat’s motor revs as Siddons accelerates, and people laugh]
Moutinho: Henry Thoreen, a marine tech, was the first to get out.
Siddons: You want to grab the poker?
Thoreen: Let’s do it.
Whitmore: People are watching on the bridge, Henry [laughs]!
Moutinho: Using a long metal stick, Henry poked the icy ground in several spots to ensure it was stable.
Siddons: Poke a bit back towards us, Henry, just to get an idea if there is a range on the bow that we need to worry about.
[CLIP: Thoreen continues to poke the ground]
Moutinho: The snow can be misleading. Sometimes it is too fluffy to walk on. Other times it hides a layer of unstable, slushy ice.
Thoreen: Oh, this is nice and stable.
Moutinho and researchers (tape): Woo-hoo!
Moutinho: The researchers carried their heavy equipment onto the ice.
Whitmore: The tubes, the shovels, the buckets.
[CLIP: People walk through the snow]
Moutinho: Everyone also brought a personal dry bag with food, water, extra pairs of winter clothes and a bottle to pee in if necessary. We would be on the ice for up to six hours, so nature just might call. But tinkling on an ice floe in Antarctica isn’t exactly straightforward. Diane Hutt, a U.S. Antarctic Program field supervisor, explained why during a safety training onboard.
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