About

Welcome to the 13th International Workshop on Long-Term Changes and Trends in the Atmosphere (TRENDS2026), which will be held from May 18 to 22, 2026. The TRENDS workshop was planned to be held once every two years, and has been successfully held 12 times in different countries. Since the first time gathering in India (1999), our committee organized the workshop in Czech Republic (2001), Bulgaria (2004), Finland (2006), Russia (2008), USA (2010), Argentina (2012), UK (2015), Germany (2016), China (2018), Finland (2022), and Spain (2024). The 13th workshop will come to Beijing, China, and is organized by the Institute of Geology and Geophysics, Chinese Academy of Sciences. 

The TRENDS2026 workshop will be a premier gathering of scientists and researchers from different countries dedicated to advancing our understanding of evolution in the middle and upper atmosphere over decades to longer periods. This workshop aims to synthesize cutting-edge research on observed and projected changes in atmospheric composition, dynamics, and chemistry, discussing the roles of greenhouse gases, aerosols, geomagnetic and solar variations, etc. During this workshop, we will bridge observational analyses, model simulations, and theoretical insights to unravel the drivers, impacts, and uncertainties of the long-term changes and trends. The workshop topics include:

• Observed trends and long-term variations in the middle atmosphere

• Modeled and predicted trends and long-term variations in the middle atmosphere

• Trends and long-term changes in the ionosphere and thermosphere

• Dynamic, physical, chemical, and radiative mechanisms of trends and long-term variations

• Role of the middle atmosphere for climate•  Miscellaneous