After Indonesia's Tsunami-Earthquake Disaster, Scientists Look For Cause

Jakarta: Almost a week after a quake-tsunami wreaked devastation in central Indonesia, scientists are zeroing in on what they believe caused the highly unusual natural disaster.

The 7.5 magnitude earthquake hit off Sulawesi island Friday and sent destructive waves charging into the coast, reducing buildings in Palu to rubble and sweeping people to their deaths.

The city was not regarded as being at high-risk of a tsunami and was left grossly unprepared for the catastrophe, which has so far claimed more than 1,400 lives with hundreds more injured and missing. 

Now experts are piecing together the unlikely chain of events which laid waste to Palu.

The quake was a sideways -- rather than vertical -- movement of tectonic plates, seen as unlikely to generate a tsunami.

p3lkbr6"It's very unlikely the earthquake alone could generate a tsunami of that size", tsunami experts have said. 

But after sifting through mounds of data, scientists believe that the powerful tremor occurred over the vast length of a fault line, triggering underwater landslides that caused the tidal waves.

"This is an earthquake that is not the standard mechanism to generate a tsunami," Costas Synolakis, director of the University of Southern California's Tsunami Research Center, told AFP.


"It's fairly rare."

When the monster waves did roll in, their force was intensified as they rushed down a narrow bay into Palu.

In recent years Sumatra has been the main focus of authorities' concern when it comes to tsunamis as Aceh, on the island's northern tip, was devastated by a deadly quake-triggered tsunami in 2004. 

Officials fear another major quake and tsunami are inevitable at some point on the highly volatile fault line off the island's west coast, meaning there was greater vigilance towards the threat than in Sulawesi.

Apart from a handful of tsunami experts, few seemed worried that the fault line that cut through Palu would produce a tsunami, particularly as it is what is known as a "strike-slip" fault, where tectonic plates move sideways. 

In the Aceh tsunami and the majority of others, destructive waves were generated by a violent upward thrust of the Earth's crust, not a sideways movement.

But such was the force of the quake off Sulawesi and the aftershocks that followed, one or more underwater landslides are believed to have occurred that displaced huge quantities of water and sent waves barrelling into the coast.

'Have to learn from this'

"There is reasonable confidence that this tsunami was triggered at least partially by a landslide," Adam Switzer, a tsunami expert from Nanyang Technological University's Earth Observatory of Singapore, told AFP.

"It's very unlikely the earthquake alone could generate a tsunami of that size."

Even before the tsunami hit, the quake and the aftershocks that followed caused widespread devastation along the Sulawesi coast, with many buildings left in ruins and huge cracks ripped in roads. 

But with officials not expecting such a catastrophic event in the area, Palu seemed ill-prepared. 

A tsunami alert was issued at the national level when the quake hit but was lifted soon afterwards and it is not clear if there was an effective mechanism to relay the warning to people on the ground in Sulawesi. 

And the city's tide-monitoring station, which could have detected the destructive waves, was broken on the day, authorities have admitted.

But while many in Indonesia were surprised that the disaster hit Palu, scientists say there are other examples of such quakes. 

Of about 35 tsunamis documented since 1992, four are believed to have been caused by quake-triggered undersea landslides, but none were in Indonesia, according to Synolakis.

Despite the criticism that authorities were unprepared, seismologists have been more forgiving -- they say the chain of events was so complicated it would have been hard for even advanced warning systems to detect the tsunami.

"This is something the automated systems could not really anticipate," Synolakis said. 

Switzer said and his colleagues were working flat out to figure out exactly what happened, and it would likely be a long process.

"We really need to make sure that we understand this event, because we have to learn from this," he said.

Scientists Look to Jupiter, Saturn's Moon Titan for Global Warming Insight

By analyzing methane in the skies of Jupiter and Saturn's moon Titan, scientists are now pinpointing what effects this global warming gas is having on Earth, a new study finds.

Greenhouse gases warm the planet by trapping heat from the sun. The greenhouse gas that most often makes news is the carbon dioxide generated in great amounts by the burning of fossil fuels. However, methane is an even more potent greenhouse gas, pound for pound capable of warming the planet more than 25 times more than carbon dioxide over the span of a century, according to the Intergovernmental Panel on Climate Change (IPCC).

In the new study, researchers focused on the most poorly understood aspect of the role of methane in global warming — how much short-wavelength solar radiation it absorbs. Previous estimates from the IPCC regarding the effects of increased methane emissions on global climate omitted the impact of shortwave absorption. [Photographic Proof of Climate Change: Time-Lapse Images of Retreating Glaciers]

Recent climate models are designed to account for shortwave absorption of methane. However, their accuracy is limited by uncertainties in how well methane absorbs shortwave radiation. Whereas the carbon dioxide molecule has a relatively simple linear shape, methane has a more complex tetrahedral shape, and the way it responds to light is also complicated — too much so to pin down in the lab.

Instead, scientists examine the atmospheres of Jupiter and Saturn's largest moon Titan, which both have "at least a thousand times greater concentration of methane than Earth's atmosphere," study co-author Dan Feldman, a climate scientist at Lawrence Berkeley National Laboratory in Berkeley, California, told Space.com. As such, these celestial bodies can serve as "natural laboratories" for investigating sunlight's effects on methane, he explained.

The scientists analyzed data of Titan from the European Space Agency's Huygens probe, which landed on the big moon in January 2005, and of Jupiter from NASA's Hubble Space Telescope. This helped pinpoint how methane absorbs various short wavelengths of sunlight, data the researchers plugged into climate models of Earth.

The scientists found the global warming effects of methane are likely not uniform on Earth, but vary over the planet's surface. For instance, since deserts near the equator have bright, exposed surfaces that reflect light upward, shortwave absorption is 10 times stronger over regions such as the Sahara desert and the Arabian Peninsula than elsewhere on Earth, Feldman said.

In addition, the presence of clouds can increase methane-shortwave absorption by nearly threefold. The researchers noted these effects west of southern Africa and the Americas, and with the cloud systems in the Intertropical Convergence Zone near the equator. 

"We can really nail down the methane greenhouse effect on Earth based on observations of Jupiter and Titan," Feldman said.

These findings support previous climate models regarding methane's effects on global warming. The researchers said their work could help advance climate-change mitigation strategies by clarifying the risks different regions across the world face.

The scientists detailed their findings online Wednesday (Sept. 26) in the journal Science Advances.

19 Quakes Rock Ring of Fire in 24 Hours

“The ring is a huge geological feature and the primary source of major earthquakes and volcanoes in the world,” van der Pluijm said.

The Ring of Fire was rocked by 19 earthquakes in 24 hours. Two of the seismic disturbances registered more than 5 on the Richter scale. Experts predict more than 100 quakes measuring between 6 to 6.9 range for 2018; the figure currently stands at 75.

RELATED: At Least 69 Earthquakes Hit Ring of Fire in 48 Hours

“It’s worth remembering that one magnitude 6.5 earthquake releases the same amount of energy as 30 magnitude-5.5 earthquakes,” Ben van der Pluijm, a geologist at the University of Michigan. “So, having 20 magnitude-5.5 EQs is the same as having one magnitude 6.3.”

Two earthquakes struck off the coast of the Greek island of Crete, the United States Geological Survey (USGS) said. The quakes, measuring 4.5 and 4.4 in magnitude, occurred four minutes apart. The first 53 kilometers south-west of Tympakion and the other 55 kilometers from Tympakion.

Major tremors over the last day included a 5.8-magnitude quake which struck 30 miles east-southeast of the Solomon Islands and another 5.5-magnitude hitting 31 miles east-northeast of Fiji’s Ndoi Island, according to the USGS.

“On a yearly basis we have roughly 1500 magnitude 5-5.9 earthquakes around the world,” van der Pluijm told Express. “So far we are at roughly 1100 for 2018. So from a tectonic energy standpoint, we are expecting a lot more earthquakes in the magnitude 5-7 range, and maybe half a dozen more magnitude 7-plus in 2018.”

The dreaded Ring of Fire stretches a total of 25,000 miles from New Zealand to the tip of South America in a horseshoe shape.

“The ring is a huge geological feature and the primary source of major earthquakes and volcanoes in the world,” van der Pluijm said. “For example, Japan is in the Ring of Fire and Japan is basically one giant volcano.”

Late last month, 25 quakes were recorded in a 24-hour period, including one measuring 7.1 off the coast of New Caledonia in the South Pacific. At one point, some 69 earthquakes reportedly struck the ring over a 48-hour period.

Hidden newsprint, painting found beneath Pablo Picasso artwork

WASHINGTON: Scientists have peered into the thick layers of Spanish artist Pablo Picasso's famous Blue Period painting, unveiling a page from a 1902 French newspaper and traces of another artwork.

Researchers from National Gallery of Art in the US conducted hyperspectral infrared imaging of Picasso's Mother and Child by the Sea - a painting in the collection of the Pola Museum of Art in Japan.

The analysis revealed portions of printed text in French similar to newsprint.

Using the readable text, Keiko Imai, chief curator, Pola Museum of Art, was able to identify the source of the text as an issue of the French daily newspaper Le Journal published on January 18, 1902.

While the reason for the presence of newsprint in the paint layers is a mystery, the discovery is significant for Picasso scholars due to the proximity of the date to the artist's move from Paris to Barcelona.

The study also provided more information about a prior paint composition seen in the X-radiograph.

The infrared images also show another earlier signature by the artist in the opposite orientation.

"I was surprised and fascinated by this finding in a painting I have always admired at our museum.

We were able to officially confirm that Mother and Child by the Seawas painted after the date of the newspaper article used on the canvas," said Imai.

"We routinely focus our cameras on a sheet of paper with printed text prior to placing the painting on the easel," said John Delaney, senior imaging scientist, National Gallery of Art.

"To verify we were in good focus, we pointed the camera first at the face of the mother and to my surprise immediately saw newspaper text in her face!" said Delaney.

"The presence of a paper interleaf begins to make sense of the fine wrinkling in the surface texture and the gentle undulations observed in several areas over the surface," said Sandra Webster-Cook, senior paintings conservator, Art Gallery of Ontario (AGO) in Canada.

"It suggests that the paper does not perfectly conform to the underlying paint surface," said Webster-Cook.

"What is exciting about this finding is that the sheet from Le Journal that Keiko Imai has identified offers Picasso scholars a firm date before which the seated woman in the composition underneath was painted," she said.

"The January 18, 1902 date of the paper interleaf is also of interest, as it is known Picasso returned to Barcelona from Paris sometime in early January 1902," she said.

Picasso is commonly known to have reused canvases and often integrated elements of previous compositions into his subsequent works.

Indications of earlier compositions are often visible on the painting's surface, and can be linked to distinctive crackle patterns, different paint colours visible through cracks and abrasion or at the edges of works, and the texture of dried impasto formed from previous paint layers that do not correspond to the painting's final composition.

  • Published in Culture

Reduced energy from the sun might occur by mid-century: Now scientists know by how much

The Sun might emit less radiation by mid-century, giving planet Earth a chance to warm a bit more slowly but not halt the trend of human-induced climate change.

The cooldown would be the result of what scientists call a grand minimum, a periodic event during which the Sun's magnetism diminishes, sunspots form infrequently, and less ultraviolet radiation makes it to the surface of the planet. Scientists believe that the event is triggered at irregular intervals by random fluctuations related to the Sun's magnetic field.

Scientists have used reconstructions based on geological and historical data to attribute a cold period in Europe in the mid-17th Century to such an event, named the "Maunder Minimum." Temperatures were low enough to freeze the Thames River on a regular basis and freeze the Baltic Sea to such an extent that a Swedish army was able to invade Denmark in 1658 on foot by marching across the sea ice.

A team of scientists led by research physicist Dan Lubin at Scripps Institution of Oceanography at the University of California San Diego has created for the first time an estimate of how much dimmer the Sun should be when the next minimum takes place.

There is a well-known 11-year cycle in which the Sun's ultraviolet radiation peaks and declines as a result of sunspot activity. During a grand minimum, Lubin estimates that ultraviolet radiation diminishes an additional seven percent beyond the lowest point of that cycle. His team's study, "Ultraviolet Flux Decrease Under a Grand Minimum from IUE Short-wavelength Observation of Solar Analogs," appears in the publication Astrophysical Journal Letters and was funded by the state of California.

"Now we have a benchmark from which we can perform better climate model simulations," Lubin said. "We can therefore have a better idea of how changes in solar UV radiation affect climate change."

Lubin and colleagues David Tytler and Carl Melis of UC San Diego's Center for Astrophysics and Space Sciences arrived at their estimate of a grand minimum's intensity by reviewing nearly 20 years of data gathered by the International Ultraviolet Explorer satellite mission. They compared radiation from stars that are analogous to the Sun and identified those that were experiencing minima.

The reduced energy from the Sun sets into motion a sequence of events on Earth beginning with a thinning of the stratospheric ozone layer. That thinning in turn changes the temperature structure of the stratosphere, which then changes the dynamics of the lower atmosphere, especially wind and weather patterns. The cooling is not uniform. While areas of Europe chilled during the Maunder Minimum, other areas such as Alaska and southern Greenland warmed correspondingly.

Lubin and other scientists predict a significant probability of a near-future grand minimum because the downward sunspot pattern in recent solar cycles resembles the run-ups to past grand minimum events.

Despite how much the Maunder Minimum might have affected Earth the last time, Lubin said that an upcoming event would not stop the current trend of planetary warming but might slow it somewhat. The cooling effect of a grand minimum is only a fraction of the warming effect caused by the increasing concentration of carbon dioxide in the atmosphere. After hundreds of thousands of years of CO2 levels never exceeding 300 parts per million in air, the concentration of the greenhouse gas is now over 400 parts per million, continuing a rise that began with the Industrial Revolution. Other researchers have used computer models to estimate what an event similar to a Maunder Minimum, if it were to occur in coming decades, might mean for our current climate, which is now rapidly warming.

One such study looked at the climate consequences of a future Maunder Minimum-type grand solar minimum, assuming a total solar irradiance reduced by 0.25 percent over a 50-year period from 2020 to 2070. The study found that after the initial decrease of solar radiation in 2020, globally averaged surface air temperature cooled by up to several tenths of a degree Celsius. By the end of the simulated grand solar minimum, however, the warming in the model with the simulated Maunder Minimum had nearly caught up to the reference simulation. Thus, a main conclusion of the study is that "a future grand solar minimum could slow down but not stop global warming."

‘Breakthrough’ discovery inside Giza Pyramid baffles scientists

Scientists have discovered a secret, giant void hiding inside the Great Pyramid of Giza in Egypt. Located above the pyramid’s Grand Gallery, the 30-meter-long void inside Khufu's Pyramid remains a mystery.

Its size suggests it plays an important role in the tomb’s structure. It’s the first discovery of its kind since the 19th century.

“These results constitute a breakthrough for the understanding of Khufu’s Pyramid and its internal structure,” the scientists explained in a journal published in Nature.

READ MORE: Pyramid scheme: Mysterious chambers found hidden in ancient Giza structure

Scientists uncovered the void as part of the ScanPyramids project that dates back to 2015. The chamber was found using cosmic-ray imaging and by recording subatomic particles, a practice known as muon radiography, which bounces inside the structure providing an outline for 3D reconstruction of the space.

https://cdni.rt.com/files/2017.11/original/59fb10e0fc7e93886a8b4567.jpg© ScanPyramids mission / AFP

This method allows researchers to visualize the known and potentially unknown voids in the pyramid in a non-invasive manner.

This large void has therefore been detected with a high confidence by three different muon detection technologies and three independent analyses,” the scientists said. “While there’s currently no information about the role of this void, these findings show how modern particle physics can shed new light on the world’s archaeological heritage.”

Psychiatric medication protects developing mouse brain from birth defects

A clinically available anxiety drug safely and effectively protects against brain defects caused by the mouse version of a common human virus, finds new research published in The Journal of Neuroscience.

More than half of U.S. adults are infected with cytomegalovirus (CMV), but most people do not experience any symptoms because a healthy immune system keeps the virus in check. However, CMV infection in babies can cause unusually small brain size (microcephaly) like the less common Zika virus, deafness, blindness, mental dysfunction, and other neurological problems that can last a lifetime. There is no effective CMV vaccine, and current treatments are not recommended during pregnancy or in newborns because of their potential to cause other birth defects and cancer.

Anthony van den Pol and colleagues found that a daily low dose of the mood stabilizer valnoctamide reduced the amount of CMV in the body of infected newborn mice and suppressed further replication of the virus that had already reached the brain, without negative side effects. The treatment also normalized neurological and behavioral development in the infected mice, including impaired social interactions thought to link CMV infection and autism spectrum disorder. Finally, the authors show that the drug suppresses replication of CMV in human fetal brain cells.


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Materials provided by Society for Neuroscience. Note: Content may be edited for style and length.

Fall armyworm 'threatens African farmers' livelihoods'

Scientists are calling for urgent action to halt the spread of a pest that is destroying maize crops and spreading rapidly across Africa.

The fall armyworm poses a major threat to food security and agricultural trade, warns the Centre for Agriculture and Biosciences International (Cabi).

It says farmers' livelihoods are at risk as the non-native insect threatens to reach Asia and the Mediterranean.

The Food and Agriculture Organization plans emergency talks on the issue.

The fall armyworm, so called because it eats its way through most of the vegetation in its way as it marches through crops, is native to North and South America but was identified for the first time in Africa last year.

Cabi chief scientist Dr Matthew Cock said: "This invasive species is now a serious pest spreading quickly in tropical Africa and with the potential to spread to Asia.

"Urgent action will be needed to prevent devastating losses to crops and farmers' livelihoods."

Scientists think the caterpillar or its eggs may have reached the continent through imported produce.

Once established in an area, the adult moths can fly large distances and spread rapidly.

Army worm caterpillar The caterpillar can march like an army across the landscape / Image copyright CABI

Dr Jayne Crozier, of Cabi, said the fall armyworm's presence had now been confirmed in west Africa and was thought to be present in the south and east of the continent, many parts of which rely on maize for their staple diet.

"It's possibly been there for some time and it's causing a lot of damage now," she told BBC News.

"The recent discovery of fall armyworm in Africa will be a huge threat to food security and also to trade in the region."

The FAO is to hold an emergency meeting in Harare between 14 and 16 February to decide emergency responses to the fall armyworm threat.

It says the pest has been confirmed in Zimbabwe and preliminary reports suggest it may also be present in Malawi, Mozambique, Namibia, South Africa and Zambia.

An investigation by Cabi has found that the fall armyworm is established in Ghana.

Experts at Cabi say it could take several years to develop effective methods to control the pest.

And they say there is confusion over the identity of the fall armyworm as it is similar to other types of armyworm, which are already present in Africa.

Zambia has used army planes to spray affected areas with insecticides.

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