Interview: IPCC Report Provides Comprehensive Information for Addressing Climate Change
On October 27-29, the Working GroupⅠ of the IPCC AR5 held outreach activities in Beijing to introduce the latest fruits of climate assessment. Co-chair of Working GroupⅠQin Dahe and Thomas Stocker accepted the joint interview of China Meteorological News and Xinhua News on the current conditions of climate change and the stories behind the report.
Reporter: Why the IPCC emphasizes "human influence has been the dominant cause of the observed warming since the mid-20th century". Is it inconsistent with the human-made global warning since industrialization?
Thomas Stocker: IPCC has made a series of assessment reports since 1990 and the human influence has been more and more evident due to two reasons. The first is better observation and the second is better understanding of the physical changes in the climate system, such as the uptake of heat in the ocean, the melting of Greenland and Antarctic and the rising temperature in the atmosphere.
There are always many factors that influence the climate. And one of the important factors is the natural variability, in other words, whether you have the warm pacific or cold pacific or other natural phenomenon such as changes in solar radiance or volcano eruptions. But in addition to these natural variations, which will continue in the future. Since 1850, the concentration of greenhouse gases, most importantly carbon dioxide, in the atmosphere has increased due to emissions from the combustion of fossil fuels, land use, and cement production. Since 1950, this has played a dominant role.
Qin Dahe: This conclusion does not conflict with IPCC previous reports. Since the middle of last century, due to industrialization, fossil fuel combustion, land using, and cement manufacturing, the greenhouse gases have increased and became a major factor of global warming. According to IPCC's temperature curve, the temperature increases significantly since 1950. Therefore we say human beings play an important role in global warming since 1950.
Reporter: Following with the IPCC report, are there any adverse impacts of climate change to China in the future?
Qin Dahe: Strictly speaking, the report of climate change impact is done by the IPCC Working Group II. In the future, the global temperature will rise. In China, the temperatures in the north will rise faster than that in in the south. That will affect China's climate system. In fact, China has a lot of extreme weather/climate events in recent years, such as heavy precipitation, extreme heat wave, as well as a small number of extremely cold weather events. In the future, we may see more hot waves. The arid regions may be drier and the humid regions may have more precipitation.
Dr. Qin Dahe.
Reporter: In recent years, especially since 2007 when AR4 released, what are advancements on the global climate observations? How can it make the report to be scientifically robust?
Thomas Stocker: We have two major advances since 2007. The first one concerns on measurements based on satellites' observaton on the gravitational effect of Greenland and Antarctic. The melting of ice in Greenland and Antarctic provides us with a signal in the satellites and for the first time we can measure the mass that is lost every year across Greenland and Antarctic. This provides water to the ocean, which results in and increases sea level. For the first time the observations find that the changing glacier, Greenland mass, and Antarctic mass, combine together into a closed and consistent budget of sea level rise. We have much better understanding on sea level rise.
The second indication that is important progress since 2007 is much better observation of the ocean. We can now understand and quantify the warming of 700 meter depth water of the ocean throughout of the world, which permits us to calculate the energy budget of entire planet. The energy budget of entire planet tells us that over 90 percent of the warming has occurred in the ocean.
Reporter: In recent years, what developments are achieved on the China climate observation system and climate model/operations? How can it help to mitigate the disasters induced by climate extremes?
Qin Dahe: Since 1950s, China climate observation system has been greatly developed and formed as a system. Most areas of China are under good observation. Especially in recent years, China has installed automatic meteorological stations in some remote areas where are lack of observation data before, making China's observation data richer and more comprehensive.
Waliguan Atmospheric Background Station, built in 1980s, is very important for observing climate system. It is the only station in inland plateau areas among WMO 37 atmospheric background stations. Meanwhile, the observations of ocean, hydrology, ecology, and cryosphere have made breakthroughs in China. Currently, climate observation system has been well developed.
As for climate models, Institute of Atmospheric Physics of Chinese Academy of Sciences (CAS) and National Climate Center of CMA have made some progresses. Among the 40 models in the Working GroupⅠreport of fifth assessment report, 5 models from China participated in the assessment. In addition, China's atmospheric chemistry model, and ocean model have been applied in relevant chapters. Despite of the difficulty of Climate system research, Chinese scientists are committing to the field. We hope China's climate system models can play a greater role in the next assessment reports. I hope various sectors could strengthen collaboration in developing climate system and earth system models with high quality. It will make more contributions to the projection of global climate change.
Reporter: What are the criteria of IPCC in choosing authors? In comparison with the AR4, what are changes in authors?
Thomas Stocker: We have very clear criteria to select authors and review editors of IPCC reports. The top criteria is scientific excellence. For example, he/she has published articles in peer reviewed journal for specific topic. In research frields, the author must cover the areas of a specific chapter as defined the outline of the report. We do not look at the performance of individual authors in our assessment. The key in such an assessment is that the scientists work as an excellent team within the chapters but also within entire working group. Dr. Qin Dahe has spent a lot of efforts to build a powerful team with the election in 2010 and throughout the work in the four year report.
Every report assembles new authors team and this time we have 60 percent of the authors who did not have IPCC experience before. It is a critical element for IPCC in addition to the regional balance to have the balance of new people together with experienced colleagues who have participated in previous assessment or other assessment work in climate science.
Prof. Thomas Stocker.
Reporter: What are the backgrounds of Chinese authors? (working institutes and research fields in general) Why there is an increase of Chinese author? How does China participate in the compiling of AR5?
Qin Dahe: A total of 18 Chinese scientists, including me, have been listed among the 259 authors of IPCC AR5 WGI report. The number is significantly increased compared with 8 of AR4 and 5 of AR3. Generally speaking, Chinese authors are from three areas. One third of the authors are from CMA, State Oceanic Administration, and other sectors; one third from various institutes of CAS, and one third from universities. We selected the scientists in full accordance with the requirement of IPCC. In our team, Chinese scientists are modest and hard working. They actively discussed and exchanged views with other authors. It is very hopeful to improve the academic capacity of themselves and the Chinese team.
Reporter: Since there was Himalayas glacier mistake in AR4, do you feel pressure in making process of AR5? And how does IPCC make sure no mistakes like this to appear in AR5?
Thomas Stocker: We can not give a guarantee that there would be zero mistake, because ultimately this is work by humans for humans. Therefore we can not exclude mistake. What we have done since 2007 is to apply and revise procedures of IPCC. We formed an error protocol which informs precisely which steps have to be taken once an error has been discovered and confirmed, which steps have to be taken to correct that error. We of course hoped that with the multiple stages of worldwide review that we can reduce errors to absolute minimum in the best case.
Qin Dahe: Although we cannot guarantee 100% accuracy, we have a strict auditing system and correction mechanism. We have 2 times of reviews, one time for experts and one time for related governments. Each chapter has review author. After review, the review author should sign their name. These measures can reduce mistakes or avoid mistake, and errors can be corrected in time.
Reporter: What implications do you think are offered in AR5 for the international community to deal with on-going climate change?
Thomas Stocker: What we try to deliver is the best possible scientific information for what is one of the greatest challenge of human kind, global warming, and all the consequences of temperature rise in the world, causes such as changes of water cycle, sea level, extreme events and many others. Policy makers have responsibility to address this problem and to take decisions. With our report and our assessment, plus two assessments that will be delivered by working groups two and three on impact and on mitigation. I believe policy makers have the best possible and most comprehensive scientific information to take informed decisions.
Reporter: Are there any stories to share with us in the 4-year compiling process of working group one contribution to IPCC AR5?
Thomas Stocker: Absolutely yes. One of the unforgettable story is the first lead author meeting at the invitation of Qin Dahe took place in Kunming, China. We have an excellent start which provided good basis to form the team of working group one scientist. I remember each interesting evening with Chinese scientists and entire group in Kunming. That was the start of our journey. At The end, certainly all in our memory is very fruitful plenary over four days of very hard work in Stockholm with 52 hours of discussion with all the government representatives of the world to arrive at a understandable and comprehensive report. There a lot of work and very little sleep. We spent 52 hours with only 8 hours of sleep. But I think we together managed to put this process through.
Qin Dahe: On September 23–27 of this year, the fifth assessment report has been passed the review by more than 100 governments in Stockholm. According to IPCC regulations, Summery for Policy Makers should be reviewed line by line. Thomas and I lead the authors to answer questions from representatives of governments. The process lasted for 4 consecutive days and 4 nights. We chaired the meeting in turn over 50 hours for the last review. It was very tired. At 05:00 a.m. on September 27, we finished. At that time, we were very excited and had great sense of achievement.
Dr. Qin Dahe.
Reporter: Would you give some comment on Qin’s winning of Wolvo Environmental Prize?
Qin Dahe: At the beginning of this year, I passed the review of Volvo Environment Prize. My submitted materials are mainly from three aspects, including developing cryosphere science, researching climate change and climate system change, and formulating China meteorological development strategy and promoting data sharing. Of course it is attributed to my team. This is the first time that Chinese scientist gaining the award. I think the award means we should continually promote research of climate change science and climate system science.
I study cryosphere science for a lifetime, and now my team continues to work in this field. Since 1995, I has studied climate change science, in nearly 20 years. I collected a great amount of data and many views to formulate China meteorological development strategy. When I began to study cryosphere science, I regarded it as an interesting thing. It is my greatest pursuit to do this well.
Thomas Stocker: I guess this is long expected because Qin is a pioneer in researching the cold environment. He has been instrumental in setting up the Antarctic program of China. In together with many other colleagues he has done a travel to Antarctic and become famous for such pioneering work. I think his contribution to IPCC as a person of a large country is unique. He has been recognized as a co-chair in the 4th assessment report, when he was my boss in the AR4. I was fortunately at AR5 to work with him. Because he brought unique experience to AR5, I believe we had an extremely fruitful relationship to combine this experience from AR4. As a co-chair I thank him for his coordination efforts.
Reporter Zhang Yong
Photo by Zhuang Baiyu
Editor Shi Long