As we are about to usher in the year 2024, we would like to extend our highest respect, sincerest greetings and New Year's best wishes to all faculty, students, global alumni, and their families, leaders at all levels, friends from all walks of life at home and abroad who have been supporting the development of the Department of Earth System Science (DESS), Tsinghua University!

In the year 2023, the DESS deeply implemented the spirit of the 20th Party Congress, solidly carried out the work arrangements made by the 15th Party Congress of Tsinghua University, adhered to and strengthened the Party's overall leadership, and heightened our sense of responsibility, with a focus on moral education and high-quality development, entrepreneurship and positive actions, achieving practical results in talent training, academic innovation, cooperation and exchanges.

Breakthroughs have been made in the development of high-quality education system. The Ministry of Education have approved of the addition of an undergraduate major of Earth System Science (Science) under the category of atmospheric science in Tsinghua University. Our department has completed the periodic qualification assessment of degree authorization programs of the Ministry of Education. The "Sustainable Science" offered by Professor Liu Zhu was rated as an excellent course in Tsinghua University. Associate Professor Wang Han's "Innovative Research Methods for Postgraduates" was rated as a demonstration course of ideological and political education in Tsinghua University. Associate Professor Yu Le won the Second Prize of Excellent Instructor in the Student Research Training (SRT) Program. The Analysis Report of Postgraduate Curriculum System has been compiled, with the training objectives, teaching arrangements, teacher requirements, curriculum ideology and politics of each course adjusted in line with the basic structure of "Basic Theory Courses-Specialized Basic Courses-Specialized Courses". A new course "Atmospheric Chemistry" was offered. Meanwhile, the department continued to deepen the construction of a minor undergraduate program in "Earth System Science" and added three general courses for undergraduates. In addition, we actively participated in the construction of Xiuzhong College, and many teachers from our department served as undergraduate tutors of Zhili College, Tanwei College, Xingjian College and Xiuzhong College. At the same time, the Measures for Education and Teaching Incentives in the Department of Earth System Science has been formulated, clarifying the incentive measures for the development of teaching materials, and three publishing contracts have been signed with publishing houses for three textbooks of our department.

Excellent achievements have been scored in the training of top-notch talents. Professor Lu Hui won the Lin Feng Counselor Award (as a teacher). Lei Tianyang, a doctoral student of Class 2019, won the Tsinghua University Top-Class Scholarship (as a graduate student); Xu Yawei, a doctoral student of Class 2021, won the "December 9th" Guo Mingqiu Counselor Award of Tsinghua University. Jiang Ruijie, a doctoral student of Class 2020, was rated as a Merit Student in Beijing. Qian Yukun, a doctoral student of Class 2017, was rated Outstanding Student Cadre in Beijing; Tao Feng, a doctoral student of Class 2018, was rated as Rising Academic Star among Tsinghua University graduate students. The DESS Graduate Youth League Branch won the Work Progress Award of Tsinghua University Department Youth Leagues; Class 2021 of DESS Graduate Program won the honor of Advanced Graduate Student Collectives in Tsinghua University. Over the past year, the DESS deepened the reform of the postgraduate scholarship system, followed the spirit of “breaking away from the evaluation system relying on five aspects only”, encouraged graduate students to explore “no-man’s land for scientific research” and carry out cross-innovation research. Meanwhile, we did a good job in guiding graduates' employment, with the employment rate reaching 100% in 2023.

The Department continued to strengthen its endeavor to build a top-notch talent team. Three teachers, Lu Hui, Liu Zhu and Liu Li, were promoted to permanent professorships. Professor Guan Dabo was appointed as "Tsinghua University Chair Professor of Basic Science". Two teachers were rated as Leading Experts of National Ten Thousands Talent Program and Young Changjiang Scholars. Professor Yang Kun, Professor Zhang Qiang, Professor Guan Dabo and Assistant Professor Tong Dan were rated Clarivate’s global “Highly Cited Researchers” in 2023. Meanwhile, we have improved the academic governance mechanism, strengthened the development of our academic community, straightened out the responsibilities and functions of the scientific steering committee and the tenured professorship committee, and adjusted the academic leaders in the two disciplines of ecology and atmospheric science. We have also enriched the DESS party and government team, completed the post adjustment of the department and the optimization of the staff team. The academic atmosphere of "encouraging originality, inter-disciplinary cooperation, harmony in diversity" and caring for and respecting talents has been promoted, thus effectively stabilizing the backbone talent team. The Administrative Measures for the Appointment of Teachers in the Department of Earth System Science and the teacher post setting and talent recruitment plan have been revised, with the open teacher recruitment information for 2024 being released.

High-tech innovations have been constantly emerging. Addressing the national strategy for achieving carbon neutrality, we have strengthened organized scientific research, and continued to carry out interdisciplinary research in the fields of climate change impact and response, global carbon-neutral path construction, achieving a series of original breakthroughs. The DESS faculty have published 3 papers in major journals of Nature and Science, and more than 230 papers in SCI and SSCI-indexed journals. "Drivers of Atmospheric Composition Change and Environmental Health Effect" won the first prize of the Natural Science Award of the Ministry of Education. The Global Daily Carbon Dioxide Emission Report 2023 and the Countdown Report on Population Health and Climate Change in The Lancet in 2023 have been released. Constant efforts have been made to promote the construction of the earth system model, develop the version of CIESM 2.0 including human activities and carbon cycle simulation functions, and complete the upgrade of coupler C-Coupler3. The Key Laboratory of Numerical Simulation of Earth System, Ministry of Education, held an annual academic meeting and issued an open fund. The Field Science Observation and Research Station of the Ministry of Education on Migratory Birds and Habitat Ecology in East Asia has improved its observation and research capabilities. Tsinghua University (DESS )- The New Intelligent Surveying and Mapping Joint Research Center of Xi’an Institute of Surveying and Mapping has been inaugurated, and the prototype construction of "Tianzhou Project" (Earth-land-ocean-atmosphere super-large experimental research platform) has been steadily advanced. Representative achievements include:

1. The international research team organized by Professor Huang Xiaomeng, doctoral student Tao Feng, and Professor Luo Yiqi of Cornell University has carried out in-depth interdisciplinary research in the fields of ecology and computer science, revealing the decisive role of microbial carbon utilization efficiency on global soil organic carbon storage by using artificial intelligence and data assimilation technology. The results have been published in the form of a paper titled "Microbial carbon use efficiency promotions global soil carbon storage" in Nature.

2. Associate Professor Li Wei’s Research Group, in conjunction with many research institutions at home and abroad, has revealed the impact of global large-scale bioenergy crop cultivation on the global land water cycle, and explored the impact of different planting strategies on land precipitation and other land water balance components through biogeochemical effects. The results have been published in the form of a paper titled "Increasing Precision Over Land Due to Climate Feedback of Large-scale Bioenergy Culture" in Nature Communication. Meanwhile, the biophysical and biogeochemical effects of human-induced degradation of tropical rain forest from 1990 to 2010 have been quantitatively analyzed by using high-resolution satellite observation data. The results have been published in the form of a paper titled "Comparative biophysical and biogeochemical feedbacks on warming from tropical moist forest degradation" in Nature Earth Science.

3. The international research team led by Professor Zhang Qiang and Assistant Professor Zheng Bo of Shenzhen International Graduate School has developed a near-real-time quantitative tracking system for global wildfire carbon emissions, which inversed and quantified the spatiotemporal pattern of wildfire carbon dioxide emissions from 2000 to 2021, and systematically analyzed the drivers behind the wildfire emissions in the middle and high latitudes of the northern hemisphere in 2021. The results have been published in the form of a paper titled "Record-high CO2 commitments from bore fires in 2021" in Science.

4. Professor Guan Dabo, Assistant Professor Tong Dan and Professor Zhang Qiang's Research Group has analyzed the carbon emission characteristics of the global steel industry in detail based on the self-developed facility-level carbon emission database of the global steel industry, constructed a plant-by-plant decarbonization strategy for the global steel industry, and proposed a highly differentiated carbon neutral path for the global steel industry. The related results have been published online in the form of back-to-back papers in Nature and Nature-Climate Change titled "Global Iron and Steel Plant CO₂ Emissions and Carbon-Neutrality Pathways" and "Plant-by-Plant Reduction Strategies for the Global Steel Industry" respectively.

5. Professor Lin Guanghui's research group found that reforestation in damaged mangrove habitats can bring higher carbon sequestration benefits than mangrove afforestation itself through comprehensive analysis of many cases and literature data around the world. The research results were published in Nature Communication with the title of "Mangrove Reforestation Providers Greater Blue Carbon Benefit Than Afforestation for Mitigating Global Climate Change".

6. Professor Bai Yuqi’s Research Team, together with Researcher Li Fang’s team from the Institute of Atmospheric Physics of the Chinese Academy of Sciences, has completed the regional health effect assessment of wildfire emissions in China from 2021 to 2100, revealing the spatiotemporal distribution of health risks caused by wildfire emissions in China in different periods in the future. The results have been published in the form of a paper titled in "Projections of mortality risk attractive to short-term exposure to landscape fire smoke in China, 2021–2100: a health impact assessment study" in The Lancet Planet Health.

High-level international cooperation and exchanges have been deepening. Our department has promoted the university to establish a partnership with the World Meteorological Organization (WMO) and sign a memorandum of understanding, which will deepen cooperation around forward-looking scientific research, talent training, teacher and student exchanges, etc., improve the quality and accessibility of information services in meteorological, hydrological, environmental and health-related fields, and jointly meet the rapidly growing and changing social needs. Our department has also promoted the renewal of the agreement between Tsinghua University and the University of Exeter, and established cooperation and exchanges with the University of Melbourne, Australia. We have recommended 3 honorary academic title experts from Tsinghua University, invited foreign experts and experts from Hong Kong, Macao and Taiwan to pay over 30 visits, and sent teachers and students abroad for 146 times. In our effort to build a brand of academic exchange, the department held 39 sessions of "Zijing Forum on Global Change Science" throughout the year, and built a new academic exchange platform of "Renewable Energy Science Salon" based on the Institute of Global Change.

Just as the new bamboo outgrows the old relying on the elder’s selfless support, our progresses are inseparable from the guidance and support of members of the Scientific Steering Committee such as Academician Xu Guanhua and Academician Guo Huadong, leaders at various levels, friends from all walks of life at home and abroad, global alumni and their families! We would like to extend our sincerest gratitude to all of you again! We are looking forward to more care and support from you!

“Despite tremendous hardships in panning, we may obtain gold by blowing away all wild sand.” In the year 2024, we will, in the light of the current situation of the DESS, implement the requirements of “Action Plan of Tsinghua University for Comprehensively Implementing the Spirit of the Party’s 20^th National Congress”, and accelerate the work arrangements for the university’s 15^th Party Congress. We will strive to make greater new contributions to building a world class university with Chinese characteristics by taking fostering virtue through education as a fundamental task, serving the state as the highest pursuit, developing high-quality disciplines as the development foundation, deepening reform and opening-up as a powerful driver, and strengthening party construction as a strong backup.

We wish you good health, good fortune and much happiness in the coming New Year!

DESS, Tsinghua University

January 1, 2024