The Chinese Academy of Sciences Qinghai -Tibet: Research reveals the reasons for the "anti -high effect" of global stable isotopes.

On August 1, the Qinghai -Tibet Plateau Institute of the Chinese Academy of Sciences released news that the environmental change and multi -circle process team Yu Wusheng, a researcher at the United States Ohio State University Professor Lonnie Thompson, and Dr. Stephen Lewis, James Cook University, Australia, found that in the world, In terms of scale, from the new perspective of the stabilization of the atmospheric hydrophobic isotope, it can systematically reveal the reasons for the "anti -high effect" of different surfaces to stabilize the isotope of different plastic measographs, and put forward important suggestions on the work of reconstructing ancient heights in the future. The result was published online on July 28 in Nature Communications.

The rising history of the Qinghai -Tibet Plateau, especially the ancient height of the new -generation Qinghai -Tibet Plateau, is the focus, hotspots and difficulties in the scientific research of the earth system. Ancient height reconstruction methods are: paleontology, stabilized homogenic alpine meter, and clustering thermometer temperature meter. Among them, the method of stabilizing the ancient altitude of the isotopes is the most mature, and it has been widely used in the ancient reconstruction of ancient heights such as the Qinghai -Tibet Plateau, the Alps, the Andes, and Luoji Mountain.

The reconstruction of the ancient height of the use of stable isotope is based on the "high -programs" principle based on stable isotopes. That is, as the altitude gradually increases, the stable homogeneity in the surface medium gradually decreases. However, this method assumes that the climate conditions have basically remained unchanged for millions of years, which is obviously not in line with the actual situation. This causes the result of the reconstruction of this method inconsistent with the results obtained by other methods.

In recent years, researchers have discovered that there is an abnormal phenomenon of "anti -high -programs" in different surface mediums (including ice core, snow, rain, rain, river water, etc.) in different places around the world, that is, the stable isotopes in these mediums increase with the elevation of altitude as the altitude increases. And increase. The emergence of the "anti -high effect" theory conflicts with the theoretical foundation of the ancient alpine alpine meter, which hinders the development of ancient altitude reconstruction.

At present, the cause of the "anti -high effect" in different surface mediums in different surface media is still unknown. According to Yu Wusheng, the author of this article, the research team found that there is a "anti -high effect" in the western and Asian arid areas (from the Red Sea to the northern part of the Qinghai -Tibet Plateau), and the spatial distribution pattern and the surface The spatial distribution pattern of stabilizing the "anti -high effect" in the medium is basically the same.

Further research has found that there are two indispensable factors that occur in the "anti -high effect" of water vapor stable isotope, that is, the water vapor supply and high isotope signals of the high -the -equivalent value of the Yuanyuan District can be transmitted from the Yuanyuan District to the target area through horizontally. Studies believe that the "anti -high effect" has appeared in water vapor before precipitation. Because water vapor is the "material source" of precipitation, the "anti -high effect" of water vapor stabilized isotope is deeply imprinted in precipitation.

We know that the gradual rise in mountains such as the Qinghai -Tibet Plateau has led to the changes in the atmospheric circulation pattern in a larger range, which in turn has changed the inherent characteristics of the water vapor source area and the water vapor conveying path and water vapor stability. These changes make the application of the ancient altitude of the isotope more complicated in these regions. Therefore, before the use of stable homogenous alpine meters, it is necessary to carefully consider the effects of water vapor sources and water vapor conveying paths and its impact on the stable isotope value during different mountains.

In addition, the results of the research also provided new ideas for understanding the height of the ice core stable isotope. Professor Thompson of the cooperative author noticed that the average oxygen reputation value of the 6,700 -meter ice core on the top of the Guri Glacier on the northern part of the Qinghai -Tibet Plateau is higher than the average oxygen is equivalent to 6200 meters ice core. The high -programs have proposed an important scientific issue, which can explain the abnormal changes in the recording of the isotope for longer. " (CCTV reporter Chu Erjia)

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