Microbial processes regulate the natural cycling of materials in every ecosystem on Earth. The responses of microbial processes to increases in global temperatures are poorly described and hence poorly constrained. Temperature can drive changes in microbial processes by generating stressors that affect the activity of entire (mixed) populations or by inducing enzyme-level physiological responses characteristic of individual functional microbial groups. Higher temperatures could result in general thermal or salinity stress, influencing the activity of multiple microbial groups. Alternatively, different enzymes may display different temperature responses, with some hardly affected and others strongly stimulated or inhibited at higher temperature. Available physiological models do not adequately constrain the possible range of temperature-driven impacts on microbial dynamics, making it impossible to predict how microbial processes will operate in our changing world. Our research aims to understand how interactive microbial processes will respond to increased temperature and other complex, interlinked environmental stressors in a changing world.