[[దస్త్రం:Radiocarbon_bomb_spike.svg|కుడి|thumb|300x300px|Atmospheric <sup>14</sup>C, [[New Zealand]]<ref>{{cite journal|url=http://cdiac.esd.ornl.gov/trends/co2/welling.html|title=Atmospheric δ<sup>14</sup>C record from Wellington|accessdate=2007-06-11|journal=Trends: A Compendium of Data on Global Change. Carbon Dioxide Information Analysis Center|year=1994|publisher=Oak Ridge National Laboratory|deadurl=yes|archiveurl=https://web.archive.org/web/20140201222225/http://cdiac.esd.ornl.gov/trends/co2/welling.html|archivedate=2014-02-01|df=}}</ref> and [[Austria]].<ref>{{cite journal|url=http://cdiac.esd.ornl.gov/trends/co2/cent-verm.html|author=Levin, I.|title=δ<sup>14</sup>C record from Vermunt|journal=Trends: A Compendium of Data on Global Change. Carbon Dioxide Information Analysis Center|year=1994|display-authors=etal|deadurl=no|archiveurl=https://web.archive.org/web/20080923105819/http://cdiac.esd.ornl.gov/trends/co2/cent-verm.html|archivedate=2008-09-23|df=}}</ref> The New Zealand curve is representative for the Southern Hemisphere, the Austrian curve is representative for the Northern Hemisphere. Atmospheric nuclear weapon tests almost doubled the concentration of <sup>14</sup>C in the Northern Hemisphere.<ref>{{cite web|url=http://www1.phys.uu.nl/ams/Radiocarbon.htm|title=Radiocarbon dating|accessdate=2008-02-19|publisher=University of Utrecht|archiveurl=https://web.archive.org/web/20071209151357/http://www1.phys.uu.nl/ams/Radiocarbon.htm|archivedate=2007-12-09|deadurl=no|df=}}</ref>]]
1955 నుండి 1980 మధ్యలో అనేక దేశాలలో అణు పరీక్షలు జరిగాయి. ఈ చర్యల వల్ల వాతావరణంలో కార్బన్ - 14 నాటకీయంగా పెరిగింది. అదే విధంగా జీవావరణంలో కూడా పెరిగింది. ఈ పరీక్షలు ముగిసిన తరువాత వాతావరణంలోని కార్బన్ - 14 గాడత క్రమంగా తగ్గుముఖం పట్టింది.
The above-ground [[Nuclear testing|nuclear tests]] that occurred in several countries between 1955 and 1980 [[List of nuclear tests|(see nuclear test list)]] dramatically increased the amount of carbon-14 in the atmosphere and subsequently in the biosphere; after the tests ended, the atmospheric concentration of the isotope began to decrease.
Oneవాతావరణంలో కార్బన్ side-effectof14 theఎక్కువవడం changeమూలంగా inవచ్చే atmosphericదుష్ప్రభావం మూలంగా ఒక వ్యక్తి పుట్టిన సంవత్సరాన్ని ఖచ్చితంగా గణన చేయలేము. ప్రత్యేకంగా దంతాల ఎనామిల్ లో మరియు కంటి కటకం లో కార్బన్ carbon-14 isపరిమాణం thatపెరగడం thisమూలంగా hasరేడియోధార్మిక enabledడేటింగ్ someవిధానంలో optionsగణన (e.g.,చేయుటలో [[Bombఖచ్చితత్వం pulse|bomb-pulseఉండదు. dating]]<ref>{{cite web|url=https://journals.uair.arizona.edu/index.php/radiocarbon/article/view/3713|title=Bomb-Pulse Dating of Human Material: Modeling the Influence of Diet|archiveurl=https://web.archive.org/web/20141020085949/https://journals.uair.arizona.edu/index.php/radiocarbon/article/view/3713|archivedate=2014-10-20|deadurl=no|df=}}</ref>) for determining the birth year of an individual, in particular, the amount of carbon-14 in [[tooth enamel]],<ref>{{cite journal|url=http://news.nationalgeographic.com/news/2005/09/0922_050922_nuke_body.html|title=Radiation in Teeth Can Help Date, ID Bodies, Experts Say|journal=National Geographic News|date=2005-09-22|deadurl=no|archiveurl=https://web.archive.org/web/20070425080623/http://news.nationalgeographic.com/news/2005/09/0922_050922_nuke_body.html|archivedate=2007-04-25|df=}}</ref><ref>{{cite journal|vauthors=Spalding KL, Buchholz BA, Bergman LE, Druid H, Frisen J|title=Forensics: age written in teeth by nuclear tests|journal=Nature|date=2005-09-15|volume=437|pages=333–4|pmid=16163340|doi=10.1038/437333a|issue=7057|bibcode=2005Natur.437..333S}}</ref> or the carbon-14 concentration in the lens of the eye.<ref>{{cite journal|doi=10.1371/journal.pone.0001529|title=Radiocarbon Dating of the Human Eye Lens Crystallines Reveal Proteins without Carbon Turnover throughout Life|year=2008|last1=Lynnerup|first1=Niels|last2=Kjeldsen|first2=Henrik|last3=Heegaard|first3=Steffen|last4=Jacobsen|first4=Christina|last5=Heinemeier|first5=Jan|journal=PLoS ONE|volume=3|pages=e1529|pmid=18231610|issue=1|pmc=2211393|editor1-last=Gazit|editor1-first=Ehud|bibcode=2008PLoSO...3.1529L}}</ref>
