A Comparison of Temperature Trends of Industrial Era and pre-Industrial Age
In the past century the global temperature has increased by approximately one degree centigrade. Global climate models predict that changes in the next century could be far larger, two to six degrees centigrade by 2100. It is these changes that are one of the main concerns about climate change. It is often stated that these changes are far larger previous changes of the past and could cause life treating damages to the environment. However, is this true? There will be check of stable isotopic data, oxygen 18 and deuterium which are temperature proxies, to see if rates of temperature change over the past two thousands are truly far smaller.
In the study publically available stable isotopic data available within the NOAA paleoclimatology data website are analyzed. Of the over 200 available data sets this study will analyze results from 32 data sets of glacial ice core because yearly isotope data is available. A total of 31 of the data sets include centuries within both Little Ice Age and current (Industrial) warm periods. Fifteen ice core data sets include results from Medieval warm period, seven ice core data sets include results from Dark Age, six ice core data sets includes from Roman warm period and lastly one ice core data set includes results from Holocene Optimum period. All of this ice core data avoids one of the main concerns long instrumental records due to changing landscapes from rural to urban, which is common for instrument data with long records that is often located in or near airports of larger cities which decades ago were at the edge of the city but are now surrounded by urban development. Regressions analysis on each of the data sets are completed a decade apart from being of data set towards the present. The at least yearly observations allows all regressions to include data sets typically considered large-significant.
Comparison of resulting rates of temperature change for various centuries are compiled for time periods fully within a warm era such as present, Medieval and Roman and current (Industrial), fully within a cool period, dark age or little ice age, and lastly for transition period that include portions within both warm and cool period. Are we in a transition period or a warm period? Past warm and cool periods are typically longer than current period post 1850, for example Roman and Medieval warm periods are 600 years long.
AAPG Datapages/Search and Discovery Article #90350 © 2019 AAPG Annual Convention and Exhibition, San Antonio, Texas, May 19-22, 2019