Compound extremes are simultaneous or sequential occurrence of multiple environmental stressors over the same geographical region that collectively represent extreme hazardous conditions, or it can be concurrent occurrence of similar or distinct extremes with common drivers over multiple geographical regions. Some examples of compounding extremes include: i) drought and heatwave, ii) extreme precipitation and strong winds/storm surge, iii) hot, dry and windy conditions, and iv) spatially concurrent droughts. They represent rare states in the Earth system that expose social-ecological systems to hazardous unaccustomed environments with adverse consequences. The research in this area is relatively new and, therefore, robust frameworks for defining such extremes and evaluating their impacts are still a work in progress. We invite submissions that advance our understanding in the detection, attribution, prediction and projection of compound, concurrent and cascading extremes and their impacts at sub-seasonal to centennial timescales, using observational, modeling, and modern machine learning approaches.