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Abstract Soil moisture feedbacks that initiate, enhance, or suppress convection initiation and precipitation are important components of regional hydroclimatology. However, soil moisture feedbacks and the processes through which they operate are notoriously challenging to observe and study outside of model environments. In this study, we combine a climatological assessment of event frequency‐based measurements of soil moisture‐precipitation coupling in the central United States with a process‐based analysis of the mechanisms by which wet‐ and dry‐soil feedbacks may operate in the region. We use the Thunderstorm Observation by Radar algorithm to identify the location of convection initiation, circumventing the issue of using precipitation accumulation as a proxy for convection initiation. Results show substantial spatial variability in the climatological sign and strength of soil moisture‐precipitation coupling in the central United States, including regions that exhibit signs of both wet‐ and dry‐soil feedbacks. Within the regions with the strongest feedback signals, we find consistently strong coupling between soil moisture and the partitioning of surface heat flux, and strong coupling between surface heat flux—particularly sensible heat flux—and diurnal change in planetary boundary layer height. In all three regions assessed, the process‐based metrics confirmed the potential of wet‐ and/or dry‐soil feedbacks leading to convection initiation. 

One of the most significant challenges in the use of heterogeneous catalysts is the loss of activity and/or selectivity with time on stream, and researchers have explored different methods to overcome this problem. Recently, the coating of catalysts to control their deactivation has generated much research traction. This Review is aimed at studying different encapsulation techniques employed for controlling catalyst deactivation. Focus is given to the prevention of irreversible modes of deactivation, such as sintering and leaching. In this Review, we elaborate on different entrapment methods used to protect catalysts from deactivation in both liquid and gas reaction media. Relevant probe reactions are discussed with emphasis on the catalyst activity and stability. Challenges associated with those processes are also described with emphasis on the mass transfer limitations as a result of the coverage of the active sites. Finally, some future perspectives and areas for possible improvement are highlighted.