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<DIV class=article-heading>Nature Volume: 501<SPAN>, </SPAN>Pages: 403–407</DIV>
<DIV class=published>Date published: 19 September 2013</TIME></DIV>
<DIV class=doi>doi:10.1038/nature12534</DIV>
<DIV class=doi> </DIV>
<DIV class="received first"><FONT size=5><STRONG>Recent global-warming hiatus
tied to equatorial Pacific surface cooling</STRONG></FONT></DIV>
<DIV class="vcard no-comma"><A class=name
href="http://www.nature.com/nature/journal/v501/n7467/full/nature12534.html?WT.ec_id=NATURE-20130919#auth-1"
jQuery172008532550678198003="65"><SPAN class=fn>Yu Kosaka</SPAN></A><SUP><A
href="http://www.nature.com/nature/journal/v501/n7467/full/nature12534.html#a1">1</A></SUP>
<SPAN>& </SPAN><A class=name
href="http://www.nature.com/nature/journal/v501/n7467/full/nature12534.html?WT.ec_id=NATURE-20130919#auth-2"
jQuery172008532550678198003="66"><SPAN class=fn>Shang-Ping Xie</SPAN></A><SUP><A
href="http://www.nature.com/nature/journal/v501/n7467/full/nature12534.html#a1">1</A>,
<A
href="http://www.nature.com/nature/journal/v501/n7467/full/nature12534.html#a2">2</A>,
<A
href="http://www.nature.com/nature/journal/v501/n7467/full/nature12534.html#a3">3</A></SUP>
</DIV>
<DIV id=content class="col article-template" role=article sizset="0"
sizcache08697979643359293="27">1 Scripps Institution of Oceanography, University
of California, San Diego, 9500 Gilman Drive MC<SPAN class=mb><SPAN
class=mb> </SPAN></SPAN>206, La Jolla, California 92093-0206, USA 2 Physical
Oceanography Laboratory and Ocean–Atmosphere Interaction and Climate Laboratory,
Ocean University of China, 238 Songling Road, Qingdao 266100, China 3
International Pacific Research Center, SOEST, University of Hawaii at Manoa,
1680 East West Road, Honolulu, Hawaii 96822, USA</DIV>
<DIV class="col article-template" role=article sizset="0"
sizcache08697979643359293="27"> </DIV>
<DIV class="col article-template" role=article sizset="0"
sizcache08697979643359293="27"><FONT
size=3><STRONG>Summary</STRONG></FONT></DIV>
<DIV class="col article-template" role=article sizset="0"
sizcache08697979643359293="27">
<DIV id=author-information class="section expanded">
<DIV class=content><FONT size=3>Despite the continued increase in atmospheric
greenhouse gas concentrations, the annual-mean global temperature has not risen
in the twenty-first century<SUP><A id=ref-link-3
title="Easterling, D. R. & Wehner, M. F. Is the climate warming or cooling? Geophys. Res. Lett. 36, L08706 (2009)"
href="http://www.nature.com/nature/journal/v501/n7467/full/nature12534.html#ref1">1</A>,
<A id=ref-link-4
title="Foster, G. & Rahmstorf, S. Global temperature evolution 1979-2010. Environ. Res. Lett. 6, 044022 (2011)"
href="http://www.nature.com/nature/journal/v501/n7467/full/nature12534.html#ref2">2</A></SUP>,
challenging the prevailing view that anthropogenic forcing causes climate
warming. Various mechanisms have been proposed for this hiatus in global
warming<SUP><A id=ref-link-5
title="Solomon, S. et al. Contributions of stratospheric water vapor to decadal changes in the rate of global warming. Science 327, 1219-1223 (2010)"
href="http://www.nature.com/nature/journal/v501/n7467/full/nature12534.html#ref3">3</A>,
<A id=ref-link-6
title="Solomon, S. et al. The persistently variable [ldquo]background[rdquo] stratospheric aerosol layer and global climate change. Science 333, 866-870 (2011)"
href="http://www.nature.com/nature/journal/v501/n7467/full/nature12534.html#ref4">4</A>,
<A id=ref-link-7
title="Kaufmann, R. K., Kauppi, H., Mann, M. L. & Stock, J. H. Reconciling anthropogenic climate change with observed temperature 1998-2008. Proc. Natl Acad. Sci. USA 108, 11790-11793 (2011)"
href="http://www.nature.com/nature/journal/v501/n7467/full/nature12534.html#ref5">5</A>,
<A id=ref-link-8
title="Meehl, G. A., Arblaster, J. M., Fasullo, J. T., Hu, A. & Trenberth, K. E. Model-based evidence of deep-ocean heat uptake during surface-temperature hiatus periods. Nature Clim. Change 1, 360-364 (2011)"
href="http://www.nature.com/nature/journal/v501/n7467/full/nature12534.html#ref6">6</A></SUP>,
but their relative importance has not been quantified, hampering observational
estimates of climate sensitivity. Here we show that accounting for recent
cooling in the eastern equatorial Pacific reconciles climate simulations and
observations. We present a novel method of uncovering mechanisms for global
temperature change by prescribing, in addition to radiative forcing, the
observed history of sea surface temperature over the central to eastern tropical
Pacific in a climate model. Although the surface temperature prescription is
limited to only 8.2% of the global surface, our model reproduces the annual-mean
global temperature remarkably well with correlation coefficient <I>r</I> = 0.97
for 1970–2012 (which includes the current hiatus and a period of accelerated
global warming). Moreover, our simulation captures major seasonal and regional
characteristics of the hiatus, including the intensified Walker circulation, the
winter cooling in northwestern North America and the prolonged drought in the
southern USA. Our results show that the current hiatus is part of natural
climate variability, tied specifically to a La-Niña-like decadal cooling.
Although similar decadal hiatus events may occur in the future, the
multi-decadal warming trend is very likely to continue with greenhouse gas
increase.</FONT></DIV></DIV></DIV></FONT></BODY></HTML>