Physics Today’s online staff summarize the most important and interesting news about science from the world's top media outlets.
Ars Technica: Historical records of sea levels during the past several million years show periods during which they were as much as 20 m higher than they are currently. However, when fed climate details from the periods of highest sea levels, current computer models do not match the historical record. To attempt to correct the models, David Pollard and Richard Alley of the Pennsylvania State University and Robert DeConto of the University of Massachussetts Amherst added two physical processes not currently included in the models—hydrofracturing and cliff failures. Hydrofracturing occurs when water fills crevasses in ice sheets to such depth that the pressure from the water breaks the ice sheet even further. Cliff failures occur when a cliff of ice becomes so tall that it collapses under its own weight. Both processes can increase the calving of icebergs from ice sheets. When that occurs near the grounding line, it can accelerate the loss of a glacier trapped behind the sheet. The adjusted model predicted a much quicker and more severe loss of ice sheets, which could account for much of the historical sea-level rise.
MIT Technology Review: As microchips become smaller, photolithography, the current technique for producing them, is reaching its limits in terms of complexity and expense. A group of researchers at IBM has demonstrated a process of molecular directed self-assembly that may provide a method for making significantly smaller microchips. By carefully preparing a set of block copolymers, and guiding the molecules' positioning using existing photolithography methods, the team was able to create circuit features that were separated by just 29 nm. Current methods are limited to separations of 80 nm. The potential increase in density of microchip circuitry could lead to much smaller chips and significant advances in processing power.
Science: The Doomsday Clock is maintained by the board of the Bulletin of the Atomic Scientists (BAS) as a representation of how close the world is to a global disaster. On 22 January, BAS executive director Kennette Benedict announced that the organization would be moving the clock hands 2 minutes closer to midnight, setting the symbolic time as 11:57pm. Benedict said that the reasons for the change include the recent stalling in nuclear disarmament talks and the growing threat of climate change. The time change is just the 18th since the clock's creation in 1947. It has ranged from just two minutes to midnight in 1953 to 17 minutes to midnight in 1991.
Nature: Imad Ahmad Barghouthi, a theorist who studies space-plasma physics at Al-Quds University in Jerusalem, was detained without charges on 6 December 2014 as he crossed the border from the West Bank into Jordan. In response to Barghouthi's detainment, several international science organizations have sent letters of protest to the Israeli government and to European organizations that provide research funds to Israel. Barghouthi was on his way to Amman to catch a flight to the United Arab Emirates so that he could attend a meeting of the Arab Union of Astronomy and Space Sciences in Sharjah. Since his arrest, he has been held in an Israeli military prison without being charged under a policy that allows Israel to hold a potential security risk for three months. Jawad Boulos, Barghouthi's lawyer, believes that Barghouthi was detained because of statements he made in support of Palestinian activists during Israel's 2014 invasion of the Gaza Strip. Barghouthi is now scheduled to be released on 2 February, but could be held longer.
Science: The US Senate voted 98 to 1 to approve an amendment to the Keystone XL Pipeline bill that says climate change is real and not a hoax . Proposed by Sheldon Whitehouse (D-RI), the amendment was one of several put forward by opponents of the pipeline, which would bring oil from Canada to the US. However, it was the only one to be approved. Other amendments that further stated that climate change was directly influenced by human activity and pollution had also been proposed. The Keystone XL bill is heavily supported by Republicans, many of whom have dodged the issue of climate change by saying they aren't scientists. Some, such as James Inhofe (R-OK), had called climate change a "hoax" in the past. Before the vote, Inhofe clarified that statement by saying the hoax is that people think that humanity can change the climate.
Science: Tetrafluoromethane (CF4) is a greenhouse gas that persists in the atmosphere for 50 000 to 100 000 years. It is commonly produced by the weathering of granite and other metamorphic rocks by rainfall. Now Daniel Deeds of the US Geological Survey and his colleagues have discovered that CF4 is also produced by tectonic activity. Surprised to find the chemical in groundwater samples collected near an active fault in the Mojave Desert, the researchers then examined 14 samples taken from aquifers along part of the San Andreas Fault. All but one of the samples showed higher CF4 levels than did water that had been exposed to the air. That suggested the gas was being absorbed from stone deep underground. The researchers also found that the samples from closer to the fault had higher concentrations of the gas than did those from farther away. Whether the CF4 is produced by the fracturing of rocks during earthquakes or by pressure stresses is not clear. However, the discovery that CF4 levels are not exclusively tied to weathering means they are no longer a reliable indicator of past changes in climate.
New Scientist: The first fast radio burst (FRB) was detected in 2007, and eight more have been seen since then. However, all were found after the fact in recorded data. Now, using the Parkes Telescope in New South Wales, Emily Petroff of Swinburne University in Melbourne, Australia, and her colleagues have seen one occurring in real time. FRBs are massive radio pulses that last just a millisecond but release as much radio energy as the Sun does in an entire day. The source of these events is still unknown, but it has been proposed that they could be caused by the collapse of oversized neutron stars or by flares from neutron stars with extremely strong magnetic fields. Within seven hours of the detection by Petroff's team, other telescopes were pointing in the direction of the event. Because none detected any evidence of an afterglow, two possible sources—gamma-ray bursts and supernovae—have been ruled out.
Washington Post: This morning officials from NASA and the National Oceanic and Atmospheric Agency hosted a joint press conference to announce that the agencies' analyses of 2014 temperature data showed that the year was the warmest yet recorded. Both agencies indicated that the warming was driven by heat from the oceans, which were also the hottest ever recorded. Perhaps most notable about 2014's warmth is that it occurred without an El Niño event, which the other recent years of high warmth all had. In both analyses, the global average temperature was just fractionally warmer than the previous warmest years. The continued warming adds further support for the effects of human-driven climate change.
Science: MacMillan Science and Education, the London-based publisher of Nature and Scientific American, is owned by Holtzbrinck Publishing Group in Germany. Berlin-based Springer Science+Business Media, purchased in 2013 for nearly $3.8 billion by private equity firm BC Partners, is one of the world's largest science, technology, and medicine publishers. Yesterday, the two publishers announced that they would be merging in a deal that would see Holtzbrinck maintain 53% ownership of the joint company with BC Partners holding the rest. Combined, they estimate annual sales of $1.75 billion, a market value of more than $5.8 billion, and more than 13 000 employees. Ewald Walgenbach of BC Partners says the goal is to sell the company, most likely as a publicly traded company, within the next few years.