Unpopular snail fossils and popular global warming

Recent question. However, from a different perspective, this is also the persistence of "unpopular" and the concentration of "popular" ...

Let's talk about the popularity. This summer, the waves are followed by the high temperature, accompanied by the red warning, from the people of Li Min to the corporate government, they all feel the pressure or anxiety of climate warming. Global warming has become a hot topic of global science, society, and public attention in recent years.

The scientific community has the responsibility to answer the public's concerns and doubts. For example, how did the climate change in the past, and the current climate warming has reached the warmest degree of warmth in the past (about 10,000 years)? How to develop in the future? These are issues that cannot be avoided.

Answer these questions, there are two ways of scientific circles: (1) geological records; (2) ancient climate simulation. There are currently two ways to have contradictions and differences. Based on the geological records accumulated in more than half a century, geologists have confirmed that the new world (about 8000-4000 years) has a warm period of about 2-3 degrees higher than today. After 4000 years, the climate continues to cool down; However, the antique simulation experts did not simulate this period of warmth. The result they simulated is that the global temperature has been warming up since 10,000 years! This difference is called "The Holocene Temperator Conundrum".

Today is the continuation and projection of the past. If the geological records are recorded, the natural climate has been a cooling trend since 4000 years. It can provide precious buffer time to respond to the rapid warming of greenhouse gases and provide valuable buffer time. If according to the results of the climate, the natural climate has been heating up for 10,000 years. The chain of human activity-greenhouse gases is superimposed, which will be oiling on the fire! How did the temperature of the new world change? It is about the development of human society and has attracted much attention.

Ancient climate simulation experts believe that there is no problem with the model because the principles and algorithms of these models successfully support today's global meteorological warning, forecast and socioeconomic development. Climate simulation experts began to find the cause from geological records. They believed that geological scholars used geological records to reconstruct the medium and new warmth period temperature, which was mainly controlled by the high temperature contribution in summer, rather than the real annual average temperature signal. They remove the new world geological record temperature change trend as the new seasons deviation in summer. The relevant papers were published in magazines such as "Nature", announcing the mystery of "effectively solving" the new world temperature change, "solving the problem that has troubled climate scientists for many years."

However, many geologists do not recognize this account, because watching the characteristics of various climate and environment indicators from the characteristics of stratigraphy soil section, they are much warm in the instructions. This is because it requires the other three seasons to be colder to match the results of the simulation ...; inexplicable, but suffer from not understanding how the ancient climate model works, for some climate simulation experts The annual average temperature change of bitter reconstruction is mainly the conclusion of the summer temperature contribution, which is very wronged. My own evidence knows the most, how to prove to the academic world to reconstruct the average annual temperature signal? It is the key to replenishing partial rescue.

This is a job that needs to be concentrated on the argument. Logically: (1), you can first reveal the ability and credibility of the four seasons of temperature changes through the modern process test and verify the climate replacement index, and then establish a quantitative conversion function; (2) Then convert the four seasons of temperature and average annual temperature in the process and trend of the average annual temperature in the new world through the replacement index of geological records; Is it controlled by summer temperature?

The next difficulty is, what kind of climate replacement indicators to screen? It is generally believed that land biological indicators are relatively sensitive to seasonal climate change, but analysis and testing shows that the biological combination indicators of long life cycle (such as more than ten-century) and ultra-short life cycle (summer insects cannot speak ice) are revealing spring spring In terms of temperature changes in summer, autumn and winter, there is a relatively large scope of error, or some seasonal can not be tested; more suitable is creatures of the living cycle of the year (1-3 years), such as snails, widely distributed, many types, quantities Rich, sensitive to seasonal temperature changes, is considered to be the most suitable climate indicators that are most suitable for establishing a quantitative relationship with seasonal temperature through the modern process.

Tiantian, geographical, people, and based on the research of the research on the animal animal animal animal animal animal animal animals for many years, this thesis first successfully established a quantitative relationship between the national modern snail group distribution and the four seasons of temperature and annual average temperature. The Loess Plateau section of snail fossil records, (1) rebuilding the sequence of temperature and annual average temperature change sequence in the four seasons of the four seasons in the past 20,000 years; They all show that the warm period from 8000 to 4000, showing a clear cooling trend after 4000 years (Figure 1); (3) the contribution of the four seasons of the four seasons through the contribution of the variance. The four seasons of temperature contribute to the average temperature change (positive, negative) of the annual temperature. Among them, the contribution of the average temperature changes to the annual temperature in summer and winter is significantly greater than spring and autumn (Figure 2). The facts of temperature change trends. In other words, the trend of changes in the four seasons and annual temperature changes of the reconstruction of Snail Fossils, which shows that the new and warm period controlled by the average annual temperature change has undoubtedly existed. The trend is indeed always cooling.

Figure 1 The four seasons of the four seasons (left) of Yao County and Xichuan of the Loess Plateau, and the average temperature (right, blue diamond -shaped and thread) and analog average temperature (right brown line) are directly rebuilt.

Early New World (EH), China New World (MH) and Evening New World (LH)

Figure 2 New Shiyao County (A) and Xichuan (B) The temperature contribute to the average annual temperature contribution at different seasons, and their relationship with the season (C).

After the article was published, some antique simulation experts came to discuss, and also believed that it was necessary to find the cause from the model sensitivity and boundary conditions: in terms of model sensitivity, most of the current GCMs may be high The sensitivity to rail -driven is low; in terms of boundary conditions, related climate simulation did not consider changing the new world planting in the desert of Africa, and did not consider changes in the Antarctic sea ice.

Besides, the unpopular snail: Remember the major of the "sixth generation single transmission" of Peking University? Paramgrars are considered representatives of unpopular professional circles. Snail fossils are more unpopular among the many paleontology. There are many people who know the snails. There are very few people who use snail fossils as professional learning. There are only a handful of experts who study snail fossils.

In the early years, a group of students who studied software animal abdominal feet fossils trained by Researcher Yu Wen, a researcher at the Institute of Ancient Biological Research Institute of the Chinese Academy of Sciences, changed their careers and retired. At present, the ancient ecological research team of the Geological Earth Institute of the Chinese Academy of Sciences still has a line. Li Fengjiang As a student of Mr. Yu Wen's student (researcher Wu Naiqin), Dong Yajie, from a master's degree to a postdoctoral study, studying all the way, with the teacher, silently guarding this direction and opening up this field.

Mr. Liu Dongsheng has been cultivating this direction attentively when he was alive. He came forward in person. Researcher Chen Dezan and foreign countries invited Russeau Didier in France to cooperate with the research on the snail fossils on the Loess Plateau. In response to the confusion and problems encountered in the study, Mr. Liu said in a targeted manner, "... The research work must have its own system. This is the most important, and it is afraid that there is no system. What does this unit do ... ". In response to the research background of snail research at home and abroad at the time, the research team clarified three interconnected matters, or the system: (1) clarifying the classification of common snail fossil systems in my country; The quantitative snail combination of the environment; (3) On the basis of the above, study the record of the dust sedimentation snail fossils since the new generation of the Loess Plateau.

In the process of sorting out the classification of the snail fossil system, the three main difficulties are: (1) the difference between the classification of the living snail; (2) the relationship between the classification of snails in the European grassland area; (3) the comparison with the pattern specimen. Among them, in order to accurately identify some uncommon snail fossils, when comparing with mode specimens, it often costs a lot. Because Mr. Yan Dunjian (1943) the Chinese snail fossil model specimens, among several museums scattered in Europe, such as France, need to use various opportunities to go to Europe or France to meet and communicate. Model specimen, this is the most test patience and needs persistence.

In the past 30 years, the study of climate climate has gradually entered the transition stage from qualitative to quantitative research, provided that it is necessary to systematically analyze and establish a quantitative relationship between environmental indicators and climate with different climate with different climate. Unlike the collection of soil samples such as micro -fossils such as pollen, there are tens of grams of soil in each place. Each snail sample is at least more than ten kilograms. It can ensure that the samples in each place have snails. Although more than 20 years of hard work, there are currently only less than 400 qualified snail combinations, covering only most of the areas north of the Yangtze River in my country. Perseverance.

The hardest thing is to obtain a systematic record of the snail combination from the Hundreds of meters of the Loess Plateau with high resolution (about ~ 10cm sampling spacing). A goal was set that year: to complete a complete loess plateau snail fossil sequence of 6 million years. This should be the longest and most resolution of the new generation of new generation biosiology sequences in the world. Unfortunately, there is still a yellow land of about 200,000 years (between 2400 and 26 million years), until Wu Naiqin retires, and has not completed the collection of all snail fossils. Lying in the 150-200-meter-deep gap in Xifeng (Qingyang) in Gansu, 15 kg of samples are required for every 10 cm, and a bag should be sieved on the back of a bag. Team collaboration needs to persevere (Figure 3). Figure 3 The process of collecting snail fossils in the Loess Plateau (left) and the common type of snail fossil (right)

From the unpopular snail fossils to the popular global warming: paleo -biology is a cross discipline of life science and global science. A branch, studying the biological remains, relics, and fossils preserved in the strata, to determine the order and era of the strata, understand the history of the earth's development, and infer the laws of water and land distribution, environmental changes, deposits of mineral formation and distribution in geological history. Studying climate change and global warming is also the use of snails. It is necessary to study unpopular research into a popular person, which requires the perseverance of "unpopular" and the concentration of "popular" ...

Beautiful editor: Chen Feifei

School pair: Wanpeng

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