1/28/2014

Journal Review 20 – 27 Jan (Nature, Science, PNAS, Nature Communications)

Journal Review 20 – 27 Jan (Nature, Science, PNAS, Nature Communications)

NATURE
1. Climate change spawns bigger waves
Nature 505, 456 (23 January 2014) doi: 10.1038/505456a
Geophys. Res. Lett. http://doi.org/q2c (2014)

Sea-level pressure data from multiple global climate model simulations was used in statistical models to predict changes in ocean wave height. These showed the frequency of extremely high waves now occurring approximately once every 10 years would double or triple by the end of the century in some coastal regions. Surface wind speeds are affected by changing air temperature and sea level pressure. Rising sea levels could worsen the impacts of bigger waves.

2. Strong storms shift landwards
Nature 505, 457 (23 January 2014) doi: 10.1038/505457c
Environ. Res. Lett. 9, 014008 (2014)

Cyclone activity has shifted towards the coasts in East Asia in recent decades, resulting in storms of greater intensity making landfall over eastern China, Korea and Japan. Changing atmospheric-circulation patterns resulting from a gradual warming of the western Pacific Ocean have shifted the areas where cyclones develop, moving them to the north and west.

3. Polar drilling problems revealed
Quirin Schiermeier
Nature 505, 463 (23 January 2014) doi: 10.1038/505463a

After arriving at Lake Ellsworth in Antarctica in early December 2012, glaciologist Martin Siegert and his team had hoped to cut through the 3km thick ice sheet in a single 72-hour effort with a specially developed hot-water drilling technique to minimise air and water pollution. However, equipment failures forced them to halt this attempt. A paper summarising the problems and possible solutions is now under review by the Annals of Glaciology.

4. Rock’s power to mop up carbon revisited
Daniel Cressey
Nature 505, 464 (23 January 2014) doi: 10.1038/505464a

Scientists are now looking into weathering olivine anthropogenically so as to sequester carbon. The research is promising but there are many unknowns such as the alteration of pH due to introducing large amounts of olivine into the sea.
5. Sea drilling project launches
Jane Qiu
Nature 505, 466-467 (23 January 2014) doi: 10.1038/505466a

On 28 January, an international team of scientists is due to set sail from Hong Kong on board the research vessel JOIDES Resolution, marking the first expedition of the International Ocean Discovery Programme (IODP). Its aim is to determine the age of the South China Sea, and to resolve ongoing controversy over how it formed.

6. Ecology: Good dirt with good friends
Mark A. Bradford
Nature 505, 486-487 (23 January 2014) doi: 10.1038/nature12849

Averill et al. show that commonly assumed controls such as temperature do not explain why stores of organic matter differ across soils in temperate, tropical and boreal forests. Instead, the proposed primary control is the types of fungus with which trees form mutually beneficial relationships. This highlights the need to consider how local-scale biotic interactions shape global and regional scale carbon dynamics.

7. Climate science: A resolution of the Antarctic paradox
John King
Nature 505, 491-492 (23 January 2014) doi: 10.1038/505491a

Long-term warming of the north and tropical Atlantic may be the ultimate cause of the observed increase in Antarctic sea-ice extent which is seemingly paradoxical in a warming climate.

8. Localised sources of water vapour on the dwarf planet Ceres
Michael Küppers, Laurence O’Rourke, Dominique Bockelée-Morvan, Vladimir Zakharov, Seungwon Lee, Paul von Allmen, Benoît Carry, David Teyssier, Anthony Marston, Thomas Müller, Jacques Crovisier, M. Antonietta Barucci & Raphael Moreno
Nature 505, 525-527 (23 January 2014) doi: 10.1038/nature12918

Hydrated minerals have been found on Ceres, which is thought to be differentiated into a silicate core with an icy mantle. Water vapour has been detected around ceres, with at least 10­­­26 molecules produced per second, originating from localised sources that seem to be linked to mid-latitude regions on the surface. This could be due to comet-like sublimation or to cryovolcanism.

SCIENCE
9. Special collection on Curiosity: Exploring Martian habitability
Vol. 343 no. 6169
5 articles on the detection at Gale crater of a system of ancient environments that would have been habitable by chemoautotrophic microorganisms. 1 article on a more ancient and also potentially habitable environment detected in Noachian age rocks at Meridiani Planum. 1 article on the present radiation environment on the surface of Mars at Gale crater.

10. Climate effects of Aerosol-cloud interactions
Daniel Rosenfeld, Steven Sherwood, Robert Wood, Leo Donner
Vol. 343 no. 6169 pp. 379-380 doi: 10.1126/science.1247490

Aerosols counteract part of the warming effects of greenhouse gases, mostly by increasing the amount of sunlight reflected back to space. However, the ways in which aerosols affect climate through their interaction with clouds are complex and incompletely captured by climate models. As a result, the radiative forcing (that is, the perturbation to Earth's energy budget) caused by human activities is highly uncertain, making it difficult to predict the extent of global warming. Recent advances have led to a more detailed understanding of aerosol-cloud interactions and their effects on climate, but further progress is hampered by limited observational capabilities and coarse-resolution climate models.

11. Strong ground motion prediction using virtual earthquakes
M. A. Denolle, E. M. Dunham, G. A. Prieto & G. C. Beroza
Vol. 343 no. 6169 pp. 399-403 doi: 10.1126/science.1245678

Sedimentary basins increase the damaging effects of earthquakes by trapping and amplifying seismic waves. Simulations capture this effect but no method exists to validate these results for earthquakes that have not occurred. Using the ambient seismic field, Denolle et al. have created a new method for ground motion prediction. They applied it to magnitude 7 scenario earthquakes on the southern San Andreas fault and compared it with simulations. Substantially different shaking patterns were found but both predict strong amplification and coupling of source and structure effects.

12. Increased dust deposition in the Pacific Southern Ocean during glacial periods
F. Lamy, R. Gersonde, G. Winckler, O. Esper, A. Jaeschke, G. Kuhn, J. Ullermann, A. Martinez-Garcia, F. Lambert & R. Kilian
Vol. 343 no. 6169 pp. 403-407 doi: 10.1126/science.1245424

Glacial-interglacial dust supply cycles from the polar South Pacific indicate dust deposition was three times higher during glacial periods than interglacials for the past million years. Large-scale common climate forcings were implied, such as latitudinal shifts of the southern westerlies and regionally enhanced glaciogenic dust mobilisation in New Zealand and Patagonia.

PNAS
13. Attributing reductions in coral calcification to the saturation state of aragonite, comments on the effects of persistent natural acidification
Roberto Iglesias-Prieto, Claudia Tatiana Galindo-Martinez, Susana Enriquez & Juan P. Carricart-Ganivet
Vol. 111 no. 3 E300-301 doi: 10.1073/pnas.1318521111

The correct attribution of reductions in coral calcification rates to environmental parameters is key to predicting how coral reefs could respond under future climate change scenarios. Crook et al. report a 35% reduction in calcification rates of the coral Porites astreoides growing near submarine freshwater springs relative to specimens growing in the surrounding lagoon. The authors of this letter are of the opinion that their main conclusion identifying low aragonite saturation as the sole driver for the observed reductions in coral calcification is misleading. In a reply published in the same issue (Reply to Iglesias-Prieto et al.: Combined field and laboratory approaches for the study of coral calcification), Crook et al. maintain that their conclusion can be substantiated by their choice of corals collected and combined laboratory experiments.

14. Molecular insight into bacterial cleavage of oceanic dimethylsulphoniopropionate into dimethyl sulphide
Chun-Yang Li, Tian-Di Wei, Sheng-Hui Zhang, Xiu-Lan Chen, Xiang Gao, Peng Wang, Bin-Bin Xie, Hai-Nan Su, Qi-Long Qin, Xi-Ying Zhang, Juan Yu, Hong-Hai Zhang, Bai-Cheng Zhou, Gui-Peng Yang & Yu-Zhong Zhang
Vol. 111 no. 3 1026-1031 doi: 10.1073/pnas.1312354111

DMS is an important participant in the global sulphur and carbon cycles. The molecular mechanism of DMSP cleavage to DMS remains unclear. Li et al. solve the crystal structure of DddQ, a DMSP lyase, and give insight into the catalytic mechanism of the DMSP cleavage reaction to further understand how marine bacteria cleave DMSP to generate the climatically important gas DMS.

NATURE COMMUNICATIONS
15. Silicon isotopes indicate enhanced carbon export efficiency in the North Atlantic during deglaciation
Katharine R. Hendry, Laura F. Robinson, Jerry F. McManus & James D. Hays
Nature Communications 5, Article number: 3107 doi: 10.1038/ncomms4107

Enhanced diatom opal burial in Sargasso Sea sediments indicates that silicic acid, a limiting nutrient today, may have been more available in subsurface waters during Heinrich Stadials, millennial-scale climate perturbations of the last glacial and deglaciation. Hendry et al. use the geochemistry of opal-forming organisms from different water depths to demonstrate changes in silicic acid supply and utilisation during the most recent Heinrich Stadial.

16. Asian pollution climatically modulates mid-latitude cyclones following hierarchical modelling and observational analysis
Yuan Wang, Renyi Xhang & R. Saravanan
Nature Communications 5, Article number: 3107 doi: 10.1038/ncomms4098

Increasing levels of anthropogenic aerosols in Asia may have a huge impact on global atmosphere, but the magnitude has yet to be quantified. A novel hierarchical modelling approach and observational analysis shows Asian pollution increases the strength of winter cyclones over the northwest Pacific, increasing precipitation by 7% and net cloud radiative forcing by 1.0Wm-2 at the top of the atmosphere and by 1.7Wm-2 at the Earth’s surface.