MEDIEVAL GLOBAL WARMING
®
®
Copyright©1997-2008 by Biology Cabinet Organization
ALL RIGHTS RESERVED.
GLOBAL WARMING IN THE MEDIEVAL AGE
By Nasif Nahle
To quote this article, please write the next two lines:
Faculty of Biological Sciences. Biological Independent Society (SABIO). Autonomous University of Nuevo Leon. Conference: Global Warming. September 2006. Invited lecturer: Nasif Nahle. Taken from http://www.biocab.info/Medieval_Age_Global_Warming.html, (day) (month), (year).
INTRODUCTION
Since 2000, the Media has been spreading misleading information generated by some spurious data made by Mann et al about an “unprecedented” global warming on our planet that, supposedly, has been caused by the human beings. Nevertheless, the scientists have demonstrated that the warming on Earth has happened naturally and that it depends on other factors other than human activities. A very important warming happened through the Medieval Age. The following graph demonstrates that during that period our planet was warmed up much more that at the moment and that the human beings do not have anything to do with the climatic changes that have always happened on Earth.
CLICK ON THE GRAPH TO SEE AN ENLARGED IMAGE
The graph above these lines has been plotted from the data collected by Yang and colleagues and Moeberg and colleagues through the isotope documentation, which is most precise for knowing the climatologic conditions in the remote past.
The dark-blue line denotes the changes of temperature that happened from 800 AD, the slashed red line designates the global trend of the temperature variations, and the light-blue line denotes the level of highest variation of temperature reached in the Medieval Age.
Through 800 AD to 1420 AD the variations of global temperature anomalies were higher than the temperature anomalies reached through the last century. The warming happened in 1998, which roughly reached 0.52 °C, was more benign and shorter in time (only one year) that the anomaly occurred in 1040 AD, which was higher than 0.8 °C and persisted by almost 50 years.
Another period of warming more severe than the current warming happened during the period from 1977 to 1981, which averaged a global variation of 0.75 °C.
In the graph below these lines, I have added the data of the carbon dioxide concentration to verify that the CO2 emitted from the human activities could have some connection with the current warming; however, the collage indicates that the atmospheric CO2 concentration is increased after the warming initiated, and not the opposite. Thus, it is not the concentration of atmospheric CO2 the origin of the warming, but just the opposite, that is, the warming is the cause of the higher concentrations of atmospheric CO2.
CLICK ON THE GRAPH TO SEE AN ENLARGED IMAGE
The graph has been drawn up taking into account the data collected by Yang et al and Moeberg et al through proxies other than tree-rings, which is most precise to know the climatologic conditions in the remote past. The data on the atmospheric carbon dioxide concentration were collected from NOAA. The dark blue line denotes the happened changes of temperature from 800 AD, the slashed red line denotes the global trend of the temperature variations, and the green line denotes the variation of the carbon dioxide concentration from 800 AD up to date. Evidently, carbon dioxide has not caused the warming of our planet, and is quite clear that the increase in the atmospheric carbon dioxide concentration increases many years after to have initiated the warming of the troposphere.
