Check your compass: The magnetic north pole is on the move
By SETH BORENSTEIN
AP Science Writer
Tuesday, February 5
WASHINGTON (AP) — North isn’t quite where it used to be.
Earth’s north magnetic pole has been drifting so fast in the last few decades that scientists say that past estimates are no longer accurate enough for precise navigation. On Monday, they released an update of where magnetic north really was, nearly a year ahead of schedule.
The magnetic north pole is wandering about 34 miles (55 kilometers) a year. It crossed the international date line in 2017, and is leaving the Canadian Arctic on its way to Siberia.
The constant shift is a problem for compasses in smartphones and some consumer electronics. Airplanes and boats also rely on magnetic north, usually as backup navigation, said University of Colorado geophysicist Arnaud Chulliat, lead author of the newly issued World Magnetic Model. GPS isn’t affected because it’s satellite-based.
The military depends on where magnetic north is for navigation and parachute drops, while NASA, the Federal Aviation Administration and U.S. Forest Service also use it. Airport runway names are based on their direction toward magnetic north and their names change when the poles moved. For example, the airport in Fairbanks, Alaska, renamed a runway 1L-19R to 2L-20R in 2009.
The U.S. National Oceanic and Atmospheric Administration and United Kingdom tend to update the location of the magnetic north pole every five years in December, but this update came early because of the pole’s faster movement.
The movement of the magnetic north pole “is pretty fast,” Chulliat said.
Since 1831 when it was first measured in the Canadian Arctic it has moved about 1,400 miles (2300 kilometers) toward Siberia. Its speed jumped from about 9 mph (15 kph) to 34 mph (55 kph) since 2000.
The reason is turbulence in Earth’s liquid outer core. There is a hot liquid ocean of iron and nickel in the planet’s core where the motion generates an electric field, said University of Maryland geophysicist Daniel Lathrop, who wasn’t part of the team monitoring the magnetic north pole.
“It has changes akin to weather,” Lathrop said. “We might just call it magnetic weather.”
The magnetic south pole is moving far slower than the north.
In general Earth’s magnetic field is getting weaker, leading scientists to say that it will eventually flip, where north and south pole changes polarity, like a bar magnet flipping over. It has happened numerous times in Earth’s past, but not in the last 780,000 years.
“It’s not a question of if it’s going to reverse, the question is when it’s going to reverse,” Lathrop said.
When it reverses, it won’t be like a coin flip, but take 1,000 or more years, experts said.
Lathrop sees a flip coming sooner rather than later because of the weakened magnetic field and an area over the South Atlantic has already reversed beneath Earth’s surface.
That could bother some birds that use magnetic fields to navigate. And an overall weakening of the magnetic field isn’t good for people and especially satellites and astronauts. The magnetic field shields Earth from some dangerous radiation, Lathrop said.
Follow Seth Borenstein on Twitter: borenbears
The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.
Lunar New Year allows US companies to find prosperity too
By TERRY TANG
Tuesday, February 5
As Asian-Americans across the U.S. mark the Lunar New Year on Tuesday, they can celebrate by eating Mickey Mouse-shaped tofu, sporting a pair of Year of the Pig-inspired Nike shoes and by snacking on pricey cupcakes.
The delicacies and traditions that once made a generation of Asian-Americans feel foreign are now fodder for merchandizing. Between now and Feb. 17, Disney California Adventure Park is offering “Asian eats” that include the Mickey-shaped tofu and purple yam macarons. Nike is issuing a limited-edition Chinese New Year collection of shoes with traditional Chinese patchwork. And housewares giant Williams Sonoma has a slew of Lunar New Year dishware and its website offers a set of nine “Year of the Pig” cupcakes for $80.
Robert Passikoff, a marketing consultant and founder of Brand Keys Inc., said there’s been a “reawakening” in the last few years of the United States’ world view of China. But it’s also about differentiating your business and growing revenue, not necessarily inclusion.
“They’re not there as social workers to create harmony among the disenfranchised people,” Passikoff said. “The other side is brands are all looking for an itch, they’re all looking for some way to engage customers. And if the Lunar New Year will do it, why not?”
Chinese fast-food chain Panda Express funded a New Year’s-themed interactive exhibit inside a Los Angeles mall. “The House of Good Fortune: A Lunar New Year,” includes different rooms showcasing customs, like a room of “flying” red envelopes and a “hall of long noodles,” a customary dish that symbolizes long life.
“Crazy Rich Asians” cast member Harry Shum Jr. promoted the exhibit and brushed off those who may scoff at the company’s efforts.
“I think it’s good to be reminded of these traditions. It’s been so important for many generations before us to try and pass that on and also experience it in a new way,” Shum said.
Andrea Cherng, the Panda Restaurant Group’s chief marketing officer and the daughter of Chinese-American founders Andrew and Peggy Cherng, said she knows some Asian-Americans will roll their eyes.
“Now the reality about Panda is that we were many people’s first Chinese experience in the U.S.,” Cherng said. “But then what a fantastic opportunity for us to be able to bridge cultures and bring to them our interpretation of what’s so special about this holiday.”
Christopher Tai, 37, of San Francisco, recently bought a Golden State Warriors jersey specially made for the Lunar New Year as a gift for his girlfriend’s father. The design includes the Chinese character for “warrior.” He said the jersey shows an effort at inclusion.
“They’re recognizing an underrepresented part of their fan base,” Tai said.
But he wonders if shoppers who snap up Williams Sonoma dishware will come away learning anything.
“I feel like a lot of people are attracted to these aesthetic elements like say red, dragons, dogs or shiny gold, without really knowing the significance of the colors and symbols and what the animals mean,” Tai said.
“There’s a part of me that’s still that kid who felt my culture was very ‘other.’ From that standpoint, I’m happy to see it more mainstream,” said Lisa Hsia, 37, of Oakland, California. “But at the same time when I see Chinese New Year shoes or whatever, I have to ask, who’s putting this together and who’s it for?”
Most Chinese traditionally ring in the Lunar New Year, which is assigned one of 12 animals each year off the Chinese zodiac, with a family dinner the evening before. The meals typically include a whole chicken, a whole fish, pork, noodles, spring rolls and dumplings, whose shape resembles ancient Chinese gold ingot currency.
Other customs include giving money-filled red envelopes to children or single young adults and sharing mandarin oranges, which represent good fortune. The celebrations, which are also commemorated in Vietnam and other countries with ethnic Chinese communities, can last up to two weeks.
As Asian populations in the U.S. and social media use grow, it’s easier for people to be aware of the holiday and its customs.
Xi Chen, who is from China but teaches Mandarin to middle-schoolers in Hamilton, Massachusetts, incorporated dumpling-making as part of her Lunar New Year lesson.
“We don’t have many Asian restaurants in town. Some students told me it was the first time in their life they’ve tried dumplings,” Chen said.
Stella Loh, 39, of Los Altos, California, said as a kid, she often got questions like, “Didn’t we already celebrate the new year?”
But now, even non-Asian co-workers have been wishing her a happy new year.
“I’d never really brought it up before,” Loh said. “It’s always nice to know people who aren’t Chinese recognize a piece of your own culture.”
Follow Terry Tang on Twitter at twitter.com/ttangAP
Are sharks being attacked by killer whales off Cape Town’s coast?
February 4, 2019
Authors: Alison Kock, Marine Biologist, South African National Parks (SANParks); Institute for Communities and Wildlife in Africa, University of Cape Town, South African Institute for Aquatic Biodiversity. Tamlyn Engelbrecht, PhD Student, University of Cape Town.
Disclosure statement: Alison Kock works for South African National Parks. She receives funding from the Save Our Seas Foundation. She is affiliated with Shark Spotters and the South African Whale Disentanglement Network. Tamlyn Engelbrecht works for Shark Spotters. She receives funding from the National Research Foundation. She is affiliated with the Institute for Communities and Wildlife in Africa (iCWild) at the University of Cape Town.
Partners: University of Cape Town provides funding as a partner of The Conversation AFRICA.
Large, predatory sharks occupy the top of ocean food chains, where they play important roles in maintaining diverse and healthy ecosystems. The loss of these predators can therefore have significant impacts on ecosystems.
For a long time broadnose sevengill sharks have occupied the apex of the food chain alongside the more famous great white sharks in False Bay on the southern tip of South Africa. Both species feed on seals, dolphins, other sharks and fish.
However, the structure of the False Bay food chain began to change significantly in 2015 with the appearance of a “new” predator, shark-eating killer whales.
The change was noted with the discovery of several dead sevengill sharks by scuba divers from a popular dive site inside the Table Mountain National Park marine protected area. This site was home to an exceptionally large group of sevengill sharks. Divers could dive with up to 70 sharks on a single hour-long dive – no other place in the world had this many broadnose sevengill sharks in one place.
Initially, the cause of death remained a mystery because no dead sharks were recovered for examination. Initially fingers were pointed to humans, great white sharks or killer whales. It was only months later following the discovery of more dead sharks and examination of the carcasses by scientists that the fingers pointed straight at killer whales.
With this information in hand we set about reviewing the literature on killer whale behaviour, dietary specialisation, and population delineation globally and locally. Based on the review we hypothesised that the attacks on broadnose sevengill sharks in False Bay were possibly indicative of the arrival of a different sub‐group – or ecotype – of killer whale in the bay that feeds on sharks.
The appearance of a super predator
Since 2009 there has been a steady increase in the frequency of killer whale sightings and the number of pods in False Bay. Initially the pods in the bay were observed feeding only on marine mammals, like common dolphins and the occasional Cape fur seal.
Initially, it was believed that the killer whales frequenting False Bay and other areas along the coast predominantly fed on mammals. So, why did killer whales start killing sharks?
Evidence from our literature review points to the arrival of a different killer whale, one which targets sharks. Typically it used to occur offshore. But that seems to have changed.
At the same time as the first discoveries of the dead sharks, a local whale watching charter documented the arrival of two new killer whales in the bay in January 2015. These individuals were easily identifiable by their characteristic bent over dorsal fins, and were nicknamed “Port” and “Starboard” and were sighted near the sevengill aggregation site at the time of both incidents in 2015 and 2016.
In 2017, it is suspected that these same two killer whales were also responsible for the death of five great white sharks further up the coast in Gansbaai.
Similar to the sevengill sharks, the wound pattern was the same and the shark’s livers were missing. Examination of the carcasses by scientists showed that the sharks had large, gaping wounds between their pectoral fins and their livers were missing, while the rest of the internal organs like heart, stomach and reproductive organs were left behind.
There were distinct bite marks on the pectoral fins of the dead sharks. These evenly spaced, circular tooth impressions were identified as most likely being from a “flat-toothed” killer whale, which is rare in coastal waters. There were no bites anywhere else on the body, indicating that the killer whale (or whales) had likely pulled on the pectoral fins to open up the body cavity, to remove the liver. The sharks’ liver accounts for up to a third of its weight and is rich in fat, a nutrient that killer whales seek out.
The key questions are why have these shark specialists moved inshore and what impact will they have?
As part of our literature review we looked at a case study from Alaska, US that provided some clues.
Killer whales started targeting sea otters and caused massive declines in their abundance. The declines were documented between 1990-1997 by population surveys conducted across the Aleutian archipelago. This in turn had a knock-on effect as sea urchin (sea otter food) populations exploded. As sea urchins’ primary food is kelp, this increase resulted in the deforestation of kelp forests in the region.
Scientists speculated that the killer whales started targeting sea otters because of declines in prey species in offshore areas.
This led us to deduce that declines in offshore prey species in South Africa might therefore be one of the reasons these killer whales have moved closer to shore.
Currently, the once popular sevengill aggregation site is largely abandoned, with only rare sightings. Great white shark sightings have also declined in False Bay, possibly in part due to the presence of these killer whales. There are substantial gaps in our understanding of killer whale behavioural ecology in South Africa, but what’s evident is that the presence of these shark specialists could have profound and cascading impacts on the ecosystem.
Due to the unique predatory niche occupied by sevengill sharks in False Bay, the increased presence of these particular killer whales in False Bay could have profound impacts throughout the ecosystem.
The politics of the periodic table – who gets the credit and why
February 6, 2019
Author: Kelling Donald, Associate Professor of Chemistry, University of Richmond
Disclosure statement: Kelling Donald receives funding from The National Science Foundation, and the Dreyfus Foundation.
Partners: University of Richmond provides funding as a member of The Conversation US.
The periodic table merges scientific inquiry, international politics, hero worship, desires for structure and desires for credit.
Formally, the modern periodic table is a systematic arrangement of the known chemical elements. The table is organized in an orderly way that shows the periodic occurrence of elements with similar chemical properties. Elements with similar chemical properties are stacked one on top of another in columns; going down each column from one row to the next the atoms of the elements get larger and heavier. Such periodic variations in the properties of elements are what Dmitri Mendeleev (1834-1907) and other scientists observed and sought to summarize in tabular and other forms.
Yet, the periodic table is not as objective as that basic description may sound. And who deserves credit for its creation is also not straightforward. I am a theoretical chemist; I apply chemical principles and mathematics to answer questions and solve problems in various areas of chemistry. I’m also fascinated by the history of science and how we assign credit and name things in science. Those interests coupled with my chemistry background have led me over the years to intersections of the political and the scientific in the emergence of the modern periodic table.
There are, for instance, nationalistic tilts to the periodic table. Two elements (francium and gallium) are named for France and one each for Japan (nihonium), Germany (germanium) and Poland (polonium). Scandinavia got scandium; the elements berkelium, darmstadtium and moscovium give three cities each a spot on the table. One Swedish village – Ytterby – has claimed four elements: erbium, terbium, ytterbium and yttrium. A number of other places and people have also snagged their little rectangles on the table too, and that, in some cases, only after serious disputes.
Among the elements named after people is element number 101, mendelevium (Md), which honors Mendeleev. Resisting other self-serving instincts, a group of Berkeley scientists who discovered the radioactive Md in 1955 decided to honor the Russian scientist Mendeleev for his contributions to formulating the periodic table. With the Cold War underway, however, they had to convince the Eisenhower administration to allow them to give up a spot on the table to a deceased Russian.
Why Mendeleev, though? Did he discover the periodic table? Hardly.
Mendeleev published in 1869 a paper that organized then-known elements in an authoritative, logical and systematic way, and he boldly predicted new ones. That paper was followed by others in the early 1870s that improved on the first and demonstrated the value of a deep appreciation for the periodicity in chemistry.
He, his papers and his table garnered a lot of attention and accelerated progress in our collective understanding of the elements and their relationships to each other. But the inspiration and the data that spurred Mendeleev’s achievements were owed in huge ways to predecessors and contemporaries such as Amedeo Avogadro (1776-1856), Johann Wolfgang Döbereiner (1780-1849) and Stanislao Cannizzaro (1826-1910).
At the end of a chemical congress in Karlsruhe, Germany, in September 1860, for instance, a decisive paper by Cannizzaro on the weights of the atoms of the elements was distributed to the attendees. Mendeleev was at that meeting, and Cannizzaro’s work helped him to organize his 1869 table of 63 known elements, which he arranged according to observed chemical properties and assigned atomic weights.
Cannizzaro’s work was so convincing that another attendee of the Karlsruhe meeting, J. Lothar Meyer, reported that it felt to him as if the scales fell from his eyes as he gained a new understanding of the elements.
Mendeleev’s periodic chart appeared some nine years after the Karlsruhe meeting (1869), but by 1868 Alexandre-Émile de Chancourtois (1820-1886), William Odling (1829-1921), John Newlands (1837-1898) and Gustavus Hinrichs (1836-1923), for example, had already served up, however technically inferior, credible attempts at periodic assemblies of the elements. Newlands had also predicted the existence of other elements.
Meyer, enlightened as he was by Cannizzaro, devised tables in the 1860s before Mendeleev’s appeared. But his grand paper describing his table, which was similar to Mendeleev’s in many respects, was published in 1870, some months after Mendeleev’s 1869 paper. Predictably, a slowly festering dispute over priority eventually erupted between them.
The impressive imperfect
Does Mendeleev deserves credit for producing a superb table for his time, for advancing an understanding of how the properties of atoms are rhythmically linked, for underlining the power of that understanding and for brave predictions that pushed chemistry forward? Indeed. But great victories can have more than one hero, and the emergence of our periodic table is one such victory.
J. Lothar Meyer also contributed to the development of the periodic table.
Mendeleev’s work was neither the beginning nor the end of the charting of periodicity in chemistry. He misplaced some elements, and his table was incomplete, even with his predictions: the group of so-called noble gases, for example, was discovered in the 1890s and was not anticipated in his papers. And general chemistry students today can readily spot other deficiencies in his 1869 table, too, based on our contemporary understanding of the nature of the elements.
In brief, Mendeleev’s contribution was tremendously impressive but was also imperfect, and the value of Meyer’s contributions was already sufficiently clear as to move the Royal Society of London to award both him and Mendeleev their prestigious Davy Medal in 1892 “for their discovery of the periodic relations of the atomic weights.” Indeed, the joint award has been cited as evidence that what was seen by some to be especially valuable about Mendeleev’s table was how it accommodated (as Meyer’s also did) the elements that were known, and not so much for Mendeleev’s predictions of new elements.
Was the Royal Society hoping too, through the joint award, to muffle the disquiet about priority or credit for the increasingly indispensable table? Perhaps. But if that were the intention, they failed. In science as in politics, the temptation to be simple rather than accurate can be quite strong. Scientists still say, “Mendeleev discovered the periodic table.”
Noble intentions, political interventions
Whatever one thinks of Meyer’s versus Mendeleev’s role in the incarnation of the table, history has not treated Meyer as well as it could have. One might ask, for example, if Alfred Nobel (1833-1896), who was a contemporary of Mendeleev and Meyer (1830-1895) but who aided in no direct way our understanding of periodicity, is more deserving than Meyer or Newlands or de Chancourtois of a spot on the period table.
In my opinion, the answer is clearly no.
Even so, element 102 – nobellium – was named after Alfred Nobel, partly because he died rich enough to fund his bequest to the world of the Nobel Prizes. But there are ironies here. Nobel got a spot on their periodic table, but neither Mendeleev, Meyer, nor anyone else received a Nobel Prize for demonstrating periodicity or developing the periodic table.
Mendeleev was actually in nine Nobel Prize nominations between 1905 and 1907, but he never won. Some claim he was denied because Swedish scientist Svante Arrhenius held substantial animosity toward him. Mendeleev harshly criticized a theory (unrelated to periodicity, about how salts dissolve in water) that Arrhenius had proposed, and – although Arrhenius was not a member of the award committee – he was famous, influential and highly regarded by his peers on the Nobel Prize selection committees. But that and other Nobel Prize backstories are separate political discussions.
Politics, hero worship and jockeying for credit are often closer than desirable to scientific practice. A place where they all converge is on that great list of the chemical elements known so far to humanity.
Who has won the priority dispute? A class of minerals has been named after Meyer, but if having a private room on the periodic table is the gold standard for its fathers, then Mendelevium has answered the question.
The United Nations, scientists and science-loving people everywhere celebrate the periodic table this year for the marvelous chemical good that it has offered and continues to offer us. And we acknowledge as well its storied past, internal political warts and all.