Editing Geology (section)

===Paleoclimatology===
{{Main|Paleoclimatology}}

Geologists also obtain data through stratigraphy, [[boreholes]], [[core sample]]s, and [[ice core]]s. Ice cores<ref>{{Cite journal |author=Barnola |first1=J. M. |last2=Raynaud |first2=D. |last3=Korotkevich |first3=Y. S. |last4=Lorius |first4=C. |year=1987 |title=Vostok ice core provides 160,000-year record of atmospheric CO2 |journal=Nature |volume=329 |issue=6138 |pages=408–414 |bibcode=1987Natur.329..408B |doi=10.1038/329408a0 |s2cid=4268239}}</ref> and sediment cores<ref>{{Cite journal |author=Colman |first1=S. M. |last2=Jones |first2=G. A. |last3=Forester |first3=R. M. |last4=Foster |first4=D. S. |year=1990 |title=Holocene paleoclimatic evidence and sedimentation rates from a core in southwestern Lake Michigan |journal=Journal of Paleolimnology |volume=4 |issue=3 |pages=269 |bibcode=1990JPall...4..269C |doi=10.1007/BF00239699 |s2cid=129496709}}</ref> are used for paleoclimate reconstructions, which tell geologists about past and present temperature, precipitation, and [[sea level]] across the globe. These datasets are our primary source of information on [[global climate change]] outside of instrumental data.<ref>{{Cite journal |last1=Jones |first1=P. D. |last2=Mann |first2=M. E. |date=6 May 2004 |title=Climate over past millennia |url=http://www.meteo.psu.edu/holocene/public_html/shared/articles/JonesMannROG04.pdf |url-status=live |journal=Reviews of Geophysics |volume=42 |issue=2 |page=RG2002 |bibcode=2004RvGeo..42.2002J |doi=10.1029/2003RG000143 |archive-url=https://web.archive.org/web/20190411223135/http://www.meteo.psu.edu/holocene/public_html/shared/articles/JonesMannROG04.pdf |archive-date=11 April 2019 |access-date=28 August 2015 |doi-access=free}}</ref>