Is the demise of the Tang Dynasty related to the climate？ Scholar： It is the ＂straw＂ that overpowers camels.

　　　 The research team headed by Zhang Pingzhong, a professor at Lanzhou University, reconstructed the changing history of the Asian monsoon since 1810 through the analysis of a stalagmite, and found that there was a corresponding relationship between the weakening of the monsoon and the decline of the dynasty. In fact, this is not the first time that someone has put forward this view. Last year, Jeralt Haug, a German, published a paper in Nature, saying that the demise of the Tang Dynasty was directly related to the weakening of the monsoon, but Zhang Deer, chief paleoclimatologist of China National Climate Center, refuted this. So, is the new research credible?

　　Technical analysis monsoon weakened and the Tang Dynasty perished.

　　　　The research sample of Haug’s team is a core sample taken from Ma ‘er Lake in Huguangyan, southwest of Zhanjiang City, Guangdong Province. In this lake formed by volcanic eruption 140,000 years ago, there is a 60-meter-thick volcanic mud, which contains abundant climate and environmental information. The Haug team believes that the ancient monsoon intensity in East Asia can be revealed through the magnetic properties and titanium substance of core samples. And this directly affected the rise and fall of a dynasty.

　　　　They believe that in 751 AD, the army of the Tang Dynasty and the Arab army fought fiercely in Luoluo, an important town in Central Asia. After that, the Tang Dynasty began to decline. This happens to be in the dry period when the summer monsoon weakens. Long-term drought and lack of rain in summer led to successive years of crop failure, which provoked peasant uprisings and eventually led to the demise of the Tang Dynasty in 907.

　　　　In the same way, the Haug team also discovered another amazing secret: the same climate change occurred in Central America. Around the 9th century, there was a drought in the Caribbean that lasted for more than 100 years, and the famous Mayan civilization died out.

　　According to the literature, the wet period is sandwiched with the dry period.

　　　　Soon, Zhang Deer, chief paleoclimatologist of China National Climate Center, and Lu Longhua, director of Polar Meteorological Research Office of China Institute of Meteorological Sciences jointly contributed to Nature, refuting the views of German scientists.

　　　　"During 700-900 AD, China experienced two wet climatic periods, including a short drought period." In an article to Nature, Zhang Deer wrote, "The last 30 years before the demise of the Tang Dynasty were rainy rather than dry." Lu Longhua once told the reporter of China Youth Daily about this matter: "As a climatologist in China, it is impossible to say anything at this time."

　　　　Zhang Deer, 64, is one of the main compilers of the great work of paleoclimatology, The Collection of Meteorological Records for Three Thousand Years in China. Relevant researchers have searched and recorded 8,228 kinds of historical books for 20 years, and actually picked 7,335 kinds of citations, doing heavy textual research. When comparing the time series curve of titanium value with the historical climate record of China with accurate age, Zhang Deer found that they were obviously misaligned. Therefore, Zhang Deer questioned whether the dating of Huguangyan titanium sequence is accurate and whether it can represent the monsoon change.

　　　　Compared with the data obtained by experimental instruments, Zhang Deer believes that the historical records left by predecessors "don’t lie". She believes that China’s historical climate records are accurate after surveying, and some times can even be accurate to the month and day.