On 21 November, Academician Markku Kulmala, Director of the Institute for Atmospheric and Earth System Research (INAR) at the University of Helsinki, Academician of the Finnish Academy of Sciences, and Foreign Member of the Chinese Academy of Sciences, led a delegation to visit Nanjing University. Professor Tan Zhemin, President of Nanjing University and Academician of the Chinese Academy of Sciences, welcomed Kulmala and his delegation to the Gulou Campus. Professor Fu Congbin, Academician of the Chinese Academy of Sciences and Foreign Member of the Finnish Academy of Science and Letters, also attended the meeting.

Tan Zhemin welcomed Kulmala and his delegation on behalf of Nanjing University. He highlighted that over the past decade, Nanjing University and the University of Helsinki have achieved a number of cooperative results in areas such as discipline building, talent cultivation, research innovation and student exchange. In particular, the jointly established Nanjing-Helsinki Institute in Atmospheric and Earth System Sciences, Nanjing University (NJU Nanjing-Helsinki Institute) has become a model of higher education cooperation between China and Finland. Tan Zhemin also gave an update on the development of the Suzhou Campus, which aims to promote new engineering clusters focused on future industries and achieve breakthroughs in discipline building and new engineering fields. He highlighted Nanjing University's commitment to international collaboration and recent initiatives to enhance global engagement, including programmes such as the International Visiting Scholars Programme and the International Research Collaboration Seed Fund. He expressed the hope that faculty and students from both universities will actively participate in these programmes and take their partnership to new heights. Both universities also plan to co-host the "China-Finland University Presidents' Innovation Forum" to deepen their strategic cooperation.

Kulmala expressed his gratitude for the warm welcome from Nanjing University. He noted the deep friendship and fruitful cooperation between the University of Helsinki and Nanjing University. Next year will mark the 75th anniversary of diplomatic relations between China and Finland, which Kulmala sees as an opportunity to jointly promote cross-cultural exchanges and research cooperation, thus further contributing to the friendship between the two nations. He also expressed his hope that cooperation will continue to expand into more areas.

The meeting was attended by Ding Aijun, Associate Vice President of Nanjing University and Dean of the NJU Nanjing-Helsinki Institute, as well as representatives from relevant departments and schools.

After the meeting, Fu Congbin, Ding Aijun and others accompanied Kulmala on a tour of the Li Siguang Building, which showcased Nanjing University's long history and remarkable achievements in the field of geosciences. Kulmala expressed great admiration for the historical significance of the building and the university's excellence in geosciences.

After the visit, Kulmala gave a lecture to faculty and students entitled "The Impact of New Atmospheric Particle Formation on Air Quality and Global Climate". The lecture focused on global trends in climate change and air pollution, explored similarities and differences in aerosol research between China and Finland, and shared current research challenges and future priorities. Kulmala presented the history of the SMEAR observatory and its long-term observational studies, and emphasised the importance of establishing a global observing network. He emphasized that international cooperation is the key to tackling climate change and air pollution.

Drawing on his personal journey, Kulmala also shared valuable research experiences with students at the NJU Nanjing-Helsinki Institute, encouraging them to adopt a global perspective, boldly explore scientific unknowns and contribute to sustainable societal development. After the lecture, the students enthusiastically asked questions on topics such as academic issues, career development and research methods. Kulmala patiently answered their questions and took a group photo with everyone present, ending the event on a lively note.

Kulmala also visited the SORPES Station and the History Museum of NJU Atmospheric Sciences. He visited the NJU Nanjing-Helsinki Institute and the School of Intelligent Science and Technology at the Suzhou Campus, where he had in-depth discussions with relevant institutional leaders on topics such as the disciplinary strengths of the two universities and joint efforts to promote data science programmes at the NJU Nanjing-Helsinki Institute. Kulmala also planted a ginkgo tree in the Academician Grove at the Suzhou campus as a symbol of the friendship between the two universities.

Ding Aijun accompanied Kulmala and his delegation to a meeting with Zhang Yan, Deputy Director of Suzhou New District, and Yu Meihua, Deputy District Mayor, to discuss the future development of the NJU Nanjing-Helsinki Institute.