<P> Examples of proxies include ice cores , tree rings , sub-fossil pollen , boreholes , corals , lake and ocean sediments , and carbonate speleothems . The character of deposition or rate of growth of the proxies ' material has been influenced by the climatic conditions of the time in which they were laid down or grew . Chemical traces produced by climatic changes , such as quantities of particular isotopes , can be recovered from proxies . Some proxies , such as gas bubbles trapped in ice , enable traces of the ancient atmosphere to be recovered and measured directly to provide a history of fluctuations in the composition of the Earth 's atmosphere . To produce the most precise results , systematic cross-verification between proxy indicators is necessary for accuracy in readings and record - keeping . </P>
<P> Examples of proxies include ice cores , tree rings , sub-fossil pollen , boreholes , corals , lake and ocean sediments , and carbonate speleothems . The character of deposition or rate of growth of the proxies ' material has been influenced by the climatic conditions of the time in which they were laid down or grew . Chemical traces produced by climatic changes , such as quantities of particular isotopes , can be recovered from proxies . Some proxies , such as gas bubbles trapped in ice , enable traces of the ancient atmosphere to be recovered and measured directly to provide a history of fluctuations in the composition of the Earth 's atmosphere . To produce the most precise results , systematic cross-verification between proxy indicators is necessary for accuracy in readings and record - keeping . </P>
what is an example of a natural climate record / proxy
what is an example of a natural climate record / proxy
ice cores
ice cores