新着論文紹介(2013.10.15) Nature, Science, PNAS
◉Nature
1.Earth science: The timing
of climate change
Chris Huntingford, Lina Mercado & Eric
Post
Nature 502, 174–175 (10
October 2013) doi:10.1038/502174a
An innovative assessment of climate change calculates the year in which
ongoing warming will surpass the limits of historical climate variability.
Three experts explain this calculation’s significance compared with
conventional approaches,anditsrelevancetoEarth’sbiodiversity.
2.The projected timing of
climate departure from recent variability
Camilo Mora, Abby G. Frazier, Ryan J.
Longman, Rachel S. Dacks, Maya M. Walton, Eric J. Tong, Joseph J. Sanchez,
Lauren R. Kaiser, Yuko O. Stender, James M. Anderson, Christine M. Ambrosino,
Iria Fernandez-Silva, Louise M. Giuseffi & Thomas W. Giambelluca
Nature 502, 183–187 (10 October 2013) doi:10.1038/nature12540
They present a new
index of the year when the projected mean climate of a given location moves to
a state continuously outside the bounds of historical variability under
alternative greenhouse gas emissions scenarios. Using 1860 to 2005 as the
historical period, this index has a global mean of 2069 (618 years s.d.) for
near-surface air temperature under an emissions stabilization scenario and 2047
(614 years s.d.) under a ‘business-as-usual’ scenario. Unprecedented climates
will occur earliest in the tropics and among low-income countries, highlighting
the vulnerability of global biodiversity and the limited governmental capacity
to respond to the impacts of climate change. Our findings shed light on the
urgency of mitigating greenhouse gas emissions if climates potentially harmful
to biodiversity and society are to be prevented.
◉Science
3.Windfall for Tiny University With Outsized Ambitions
Dennis Normile
Science 11 October 2013: 182.
4.Cleaner Lakes Are Dirtier Lakes
Emily S. Bernhardt
Science 11 October 2013: 205-206.[DOI:10.1126/science.1245279]
Efforts to reduce the phosphorus input to lakes have helped to lessen
algal blooms but exacerbated nitrate pollution.
5.Waveform Tomography Reveals Channeled Flow at the Base of the Oceanic
Asthenosphere
Scott French, Vedran Lekic, and Barbara Romanowicz
Science 11 October 2013: 227-230.
Published online 5 September 2013 [DOI:10.1126/science.1241514]
6.Human Influences on Nitrogen Removal in Lakes
Jacques C. Finlay, Gaston E. Small, and Robert W. Sterner
Science 11 October 2013: 247-250.
Increased phosphorus inputs from human activities have stimulated
nitrogen removal processes in many lakes. Recent management-driven reductions
in phosphorus availability promote water column accumulation and export of
nitrogen from large lakes, an unintended consequence of single-element
management that argues for greater control of nitrogen as well as phosphorus
sources
◉PNAS
7.Iceberg discharges of the last glacial period driven by oceanic
circulation changes
Jorge Alvarez-Solas, Alexander Robinson, Marisa Montoya, and Catherine
Ritz
PNAS 2013 110 (41) 16350-16354; published ahead of print September 23,
2013, doi:10.1073/pnas.1306622110
They present simulations of the last glacial period carried out with a
hybrid ice sheet–ice shelf model forced by an oceanic warming index derived
from proxy data that accounts for the impact of past ocean circulation changes
on ocean temperatures. The model generates a time series of iceberg dis- charge
that closely agrees with ice-rafted debris records over the past 80 ka,
indicating that oceanic circulation variations were re- sponsible for the
enigmatic ice purges of the last ice age.
8.Role of orthopyroxene in rheological weakening of the lithosphere via
dynamic recrystallization
Robert J. M. Farla, Shun-ichiro Karato, and Zhengyu Cai
PNAS 2013 110 (41) 16355-16360; published ahead of print September 25,
2013, doi:10.1073/pnas.1218335110
9.Robust increases in severe thunderstorm environments in response to
greenhouse forcing
Noah S. Diffenbaugh, Martin Scherer, and Robert J. Trapp
PNAS 2013 110 (41) 16361-16366; published ahead of print September 23,
2013, doi:10.1073/pnas.1307758110
