Nat Rutter

(Univerisity of Alberta, Edmonton, Canada)

 

Professor Liu was an important part of my life for over 25 years, not only as a scientific colleague, but a very close friend.  I have a difficult time realizing he has passed on and will miss him greatly.

I can’t remember when I first met him, but most likely in the eighties during the formation of the International Geosphere-Biosphere Programme organized by the International Council of Scientific Unions to investigate  future global and climate change. We were both nominated to the scientific board of one of the core projects of the Programme called Past Global Changes (PAGES). This was important to Tungsheng and me because we, as well as most Quaternarists, realize the importance of knowing what happened in the past in order to predict global and climatic change in the future. The Committee was made up of a high number of numerical climatic modellers, some skeptical of the usefulness of Quaternary proxy data in testing computer models. Tungsheng and other Quaternarists on the Committee had an up hill battle convincing our computer modelling colleagues how important  our work was in testing the accuracy of past climate models. We prevailed and paved the way for an appreciation by climate modellers of the importance of our work, to their success in more accurate models. Tungsheng’s convictions helped in this transformation. Over twenty years later, the Committee is still thriving with Quaternary geologists making major contributions to the success of PAGES.

We were both involved in INQUA (International Union of Quaternary Research) for many years in the late eighties and nineties. This is when I worked closely with Tungsheng on INQUA matters. We were both on the executive committee, as vice presidents and later as presidents. When I was President of the Organizing Committee of the INQUA Congress in Ottawa, and later President of INQUA, Tungsheng was extremely helpful both in planning the objectives of INQUA and organizing the Commissions, as well as having his great insight into climate problems that Quaternary geology could help in solving. During this time, China was making great strides in Quaternary research and when China was awarded the INQUA Congress for 1991, Tungsheng couldn’t wait to show the world the geology of China. I helped him and his colleagues plan field trips for the Congress around China. One thing he was concerned about was the poor accommodations and road conditions in areas he wanted to visit. He said we should probably restrict our trips where we can be sure of “western – type” accommodations, and good, paved roads ensuring participants would be comfortable. Being such a kind and sensitive man, he worried about this. I finally convinced him that most of the participants would be geologists who would be used to other than first class roads and accommodations, and more importantly these people will come from around the world and want to see China, especially geology, archeology, and natural sites that they had only read about. I finally convinced him of this, and as a result trips were conducted to remote areas throughout China including a trip across Tibet, where we had to forge rivers and stay occasionally in army camps. This is the trip my wife and I were on. The people on this trip are still talking about how it was one of greatest experiences of their life. I have to admit that there were a few people that weren’t quite as enthused as the vast majority were. As we all know the Congress was a great success, and Professor Liu and his colleagues did an outstanding job. The success of the Congress and Tungsheng’s scientific reputation resulted in his, being elected President of INQUA.

As past President, I was honored to work with him for the next four years where many changes within INQUA were being made, especially in the mandate of the Commisions and  financial grant procedures. We often, however, talked about things other than INQUA and geology. This is really when I got to know him on a personal level and learned more about his values, and especially the importance of his family. I remember with great fondness one time he was at an INQUA executive meeting at my home in Canada, when he didn’t feel well. I suggested several “western” medicines. His reply was couldn’t you find me a Chinese herbal medicine pharmacy in Edmonton? I found him one in the Chinese section of Edmonton, something I didn’t know existed. He got what he needed and was soon well. Once more I ,was learning more about Chinese culture and especially the merits of Chinese medicine. I was always learning something new from Tungsheneg! One bad habit we both had was cigar smoking. We would commonly sneak out of a meeting and “light up” and discuss a variety of topics. His wife didn’t like his habit and would commonly scold me for encouraging him. Nevertheless, when I came to China, he would always have a cigar waiting for me. At the end of his term as President, at the INQUA Congress in Berlin, I was extremely honored when Tengsheng asked me to Chair the final meeting of the INQUA Council. This is when a lot of business is discussed including the election of the new executive and the selection of the site for the next Congress. This surprised me, because he was perfectly capable of running the meeting himself. When I asked him about this, he smiled and shyly said that I had more experience in dealing with unruly council members consisting mainly of Westerners!

Although Tungsheng and I spent much time together on administrative matters, it was really through science that I got to know China and the Chinese people. Sometime during our early friendship, he casually asked me if I was interested in working on loess problems in China. He suggested that I get out of Canada for a while and do something new. I should say here that I had mainly been engaged in glacial geology problems in western Canada for most of my career along with my graduate students. Although I had worked on other Quaternary problems such as paleosols and sea level changes, I had very little experience with loess. Anyhow, I said yes, I would like to investigate loess. This was the beginning of roughly 20 years of some of the most rewarding research that I have ever carried out. In addition, I learned something very important about Chinese culture, that when an agreement is reached it can be made verbally (not a written contract), and as long as everyone is honest and no one breaks their word, things work out fine. I can’t remember signing a document for anything in China, and when I reciprocated in Canada, verbal agreement was all that was necessary.

What Tungsheng suggested I do was to work on long loess/paleosol sequences in the Loess Plateau. The idea was to extract as much information as possible on past climate changes during the Quaternary. He said I could work with one of his outstanding new

Ph.D. students. This turned out to be Dr. Ding Zhongli. Needless to say, I was extremely fortunate to have him work with me. We all know the success Ding has had recently. Many studies had been undertaken on sections in the Loess Plateau, but few had complete loess/paleosol sequences to the beginning of the Quaternary. Ding had recently studied one of the most complete sections known at this time. This was the Baoji section, about 200 kilometers west of Xian, where it was possible to differentiate loess/paleosol units in the older or lower part of the section, something that hadn’t been achieved in other sections before this time. I remember with fondness working on the Baoji section, and climbing up to a humble farm house day after day, to enjoy freshly made noodles for lunch. This turned out to be one of my favorite meals in China. The farmer’s wife had not

cooked for a foreigner before and appeared to enjoy it very much.

For the next few years several of us investigated this site extensively and were able to differentiate  at least 37 major climatic changes during the past 2.6 Ma. During this time Ding, Professor Liu, and I, plus others from the Institute of Geology and Geophysics, discovered that grain - size could be used as a climatic proxy. Simply put, as the source area was to the northwest and west, and the dominant wind direction was from the northwest, we found that grain - size varied according to wind intensity- greater intensity during colder periods (winter monsoons) and less intensity, and at times little deposition, during  warmer periods (summer monsoons). This, in turn allowed us to demonstrate that Milankovitch forcing was the cause of the major climatic changes that were at least hemispheric in scale, if not worldwide. Other discoveries included the usefulness of magnetic susceptibility in determining climatic variations. One of our more important accomplishments was the construction of an orbital time scale from grain – size data. It was exciting for me to be part of this exercise. It was the first time that an orbital time scale was constructed from terrestrial material. It is probably safe to say that the

loess/paleosol sequences in the Chinese Loess Plateau are the most complete record of terrestrial  Quaternary deposits found anywhere in the world. It should be acknowledged  that our orbital time scale has been modified since the original publication. During this initial work on long records, Tungsheng made it possible for Ding to come to the University of Alberta for an extended visit to work on loess/paleosol problems. This was the first time Ding had been, I think, outside China, or at least to North America. This I really appreciated, because it gave me a chance to know Ding better.

Tungsheng made it possible for me, and my Canadian colleague, Professor Ted Evans to continue to work in China in conjunction with some of the best people in the Institute of Geology and Geophysics. This included Ding, and among others, Profs. Guo Zhentang, Liu Jiaqi, Han Jingtai, Sun Jimin, and Yang Xiaoping. We investigated loess/paleosol sections along widely spaced  transects in the Loess Plateau, concentrating on material of the last glacial cycle. We were able to identify and correlate isotope stages 1 through 5 as well as climate changes on the millennium time scale. One of my graduate students, Dean Rokosh, was able to carry out field work in China on this project, and eventually received his Ph. D at the University of Alberta. So for many years, much of my research time was concentrated in China associated  with climate change problems. However, during these years, I was invited by Profs. Li Jijun and Zheng Benxing of the Institute of Glaciology and Geocryology in Lanzhou to travel to the Tibetan Plateau and participate in conferences and field trips. This was because of my background and interest in glacial geology. This was beneficial for me as I was able to relate my work in glacial stratigraphy and permafrost phenomena to the glacial geology of the Tibetan Plateau. In turn, this information aided in a better understanding of climate changes based on evidence from glacial geology and that gained from the loess/paleosol stratigraphy.

My many trips to China arranged by Tungsheng and Ding, were not always work related. They made sure that I saw many of the major tourist attractions, such as the karst topography in Guilin, terracotta soldiers in Xian, The Great Wall near Beijing and Yulin, and the major attractions in Beijing. Other trips in China arranged by Chinese friends included the sights of Shanghai, the Cambrian soft- bodied fossil site near Kunming, the paleontology museum in Nangjing and the University of Science and Technology at Hefei (where I gave lectures). One trip, in 2001 that stands out for my wife, Marie, and me, is a trip that Tungsheng arranged for us, and Dr. Jim Bowler and his wife, Joan, led by Dr. Han Jiamao, that took us from Hong Kong, Shenzhen, Guangzhou and then by train to Beijing. This enabled us to see almost daily the changes that were taking place in China. One thing I clearly remember on this trip was at a meeting in Shenzhen where Tungsheng was asked to deliver a talk. This is when power point presentations were relatively new. Like me, and others of my generation, Tungsheng knew how to push the button to advance the next slide but not much beyond that. Anyhow, during the talk he pushed the button but nothing happened. He looked up and could only smile. Within two seconds at least six people rushed to the podium to help and solve the problem. I relate this to illustrate the great respect and admiration his colleagues had for Professor Liu. They wanted to make sure that he suffered no embarrassment. Another memorable trip was in 2004, when Marie and I were invited to spend a month at the Institute of Geology and Geophysics where I was able to carry out research and get reacquainted with geologists I had known earlier and meet some of the new geologists and graduate students, such as Dr.Yang Shiling, and I was able to learn, first hand, how the Institute functioned.

I mentioned the trips I have had to China, outside of research, to emphasize that through Tungsheng and others, I have learned a great deal about the country and it’s people, and how important China has become to my life. It was all started by Professor Liu back in the eighties by suggesting I should come to China and study loess. I didn’t know at the time that I would be going back and forth to China for a large part of my life, over 20 years! One of my proudest moments was when the Chinese Academy of Sciences awarded me an Honorary Professorship. I think Professor Liu was thanking me for the years that we had been working together, both scientifically and administratively. I, of course, hope to continue to go to China and visit Tungsheng’s family, who incidentally  I became close too, as well as to see my friends, and as an Honorary Professor at the Institute. The Institute has always has always made me feel welcome.

Professor Liu was an extremely important in my life, as a friend, mentor, and scientific colleague. He opened the doors for me on the importance of loess and paleosols in climate change reconstruction, and perhaps more important, China and its culture and people. He has left me with many good friends that I will cherish for the rest of my life. I shall miss Tungsheng greatly, but his memory will not be forgotten.