On the evening of October 25, 2022, the tenth lecture of the Guanya Cross Disciplines Statement was held simultaneously online and offline in Room 512, Jia Geng Building 2. Chaired by Associate Professor Xiong Feng, Professor Duan Anmin from the College of Ocean and Earth Sciences, Xiamen University, was invited to give a lecture titled "History, Current Situation and Future Prediction of Climate Change". Professor Duan Anmin, Associate Professor Hu Jun, Dr. Zhang Chao, Dr. Yang Xianyi, Dr. Cao Shutao from the College of Ocean and Earth Sciences, Assistant Professor Zhang Yang, Associate Professor Xiong Feng, Assistant Professor Guo Rui, Assistant Professor Li Shengnan, Assistant Professor He Yuan, and other full-time researchers and PhD students from the School of Management, a total of 56 people attended this lecture.
Currently, the Earth's climate system is undergoing dramatic changes, with the Arctic warming dramatically and the sea ice extent and thickness decreasing sharply. In the context of global warming, sea surface temperatures in the tropical Indian Ocean and western Pacific Ocean are increasing, and the tropics are expanding to mid-latitudes, while extreme precipitation is increasing dramatically, leading to changes in global precipitation distribution. To better study these changes, scholars have collected observations from multiple sources (e.g., station observations, field observations, and satellite observations), combined with the theoretical basis of atmospheric motion, and conducted numerical simulation studies with the help of climate system model tools, etc.
During the long period of geological history, the Earth's temperature has undergone drastic changes, possessing different forms such as hot-room Earth, ice-room Earth, greenhouse Earth and snowball Earth. A look at the evolution of the Earth's temperature over 600 million years reveals that: the vast majority of the period was warmer than today. The temperature trend has been decreasing from 50 million years to the present. And from 1 million years to the present, the Earth has had a clear cycle of ice ages, corresponding to different stages of biological and human development. Yet bringing the perspective back to the present reveals that the climate system is undergoing dramatic changes that differ from historical cycles. Greenhouse gases have increased dramatically, global warming has increased dramatically, land precipitation and atmospheric water vapor content have increased dramatically, Arctic sea ice has decreased dramatically, Northern Hemisphere snowpack has declined dramatically, sea level and ocean heat content are rising, and ocean acidification has increased dramatically. Based on these changes, which are different from the cyclical turnover, most scholars believe that human activities are the most important factor causing climate change since the Industrial Revolution. Climate change has affected every region inhabited by humans, while human activities have also increased the frequency of extreme climate events. Looking into the future, Professor Duan Anmin suggests that all regions of the globe are expected to be affected by simultaneous changes in multiple climate factors.
Combining the history, current situation and future of climate change, Professor Duan Anmin pointed out that, throughout human history, the extent of climate change since the industrial revolution has been unprecedented. With the continuous advancement of research technology, scholars have gradually determined that the impact of human activities on climate has changed from likely (70%) to very likely (90%) and nowadays extremely likely (99%). As climate warming is likely to increase further in the future, reducing emissions is an inevitable choice for adaptation and response to climate change.
At the end of the lecture, Professor Duan Anmin and the online and offline teachers and students had a communication and discussion. The lecture was successfully concluded!
