The summer seasons of the last decades in the north of Western Siberia turned out to be the warmest for the last 7,000 years.
The summer seasons of the last decades in the north of Western Siberia turned out to be the warmest for the last 7,000 years. In previous millennia, air temperatures had been dropping gradually, with fluctuations in one direction or the other. However, in the XIX century began to rise and in recent decades reached the highest numbers. This was found out by the dendrochronologists of the Institute of the Plant and Animal Ecology, Ural Branch, Russian Academy of Sciences and Ural Federal University, who spent 40 years creating a superlong tree-ring chronology, based on the width of the annual rings of semi-fossil trees on Yamal Peninsula. During this time, they were able to study information on summer temperatures for 7,638 years. The scientists published the results of the study and their findings about temperatures in Western Siberia in the journal Nature Communications. The research is supported by the Russian Science Foundation (project No. 21-14-00330).
"Due to cyclic changes in the orbital parameters of the Earth in the circumpolar latitudes of the Northern Hemisphere there is a gradual decrease of solar energy in the summer months. This phase began about 8-9 thousand years ago and continues now. However, the data of annual rings show that since the middle of the 19th century the trend began to change, the temperature began to rise very rapidly. It reached the highest values in last decades," explains Rashit Hantemirov, Leading Researcher at the Laboratory of Dendrochronology of Institute of the Plant and Animal Ecology, Ural Branch, Russian Academy of Sciences and UrFU Laboratory of Natural Science Methods in Humanities.
Whatever period of time in the interval from 30 to 170 years was taken by the researchers, the warmest was the one that ended with the last year of reconstruction. For example, the average value for the last century is higher than the temperature of any other randomly taken centennial interval in the past.
Read more at Ural Federal University
Image: The researchers set slices of the tree trunks up to dry (Credit: Vladimir Kukarskih)