A current direction in climate research is to study how changes in cloud-related atmospheric radiative heating impact both clouds and their environment. Recent research suggests atmospheric cloud radiative effect (ACRE) as an important feedback mechanism for enhancing the development of tropical convective systems and the persistence of convective self-aggregation in idealized numerical simulations. This motivates the hypothesis that longwave radiative heating associated with the presence of clouds in deep mesoscale convective regions can induce a secondary thermally-direct circulation, which leads to low-level moisture convergence into deep convective regions and thus strengthens the organization of mesoscale convective systems (MCS) and the contrast of ACRE between the MCS and non-MCS regions. Here, we explore this hypothesis with multiple independent satellite and reanalysis datasets and compare the relationship between a couple of convective aggregation metrics and ACRE associated with MCS and non-MCS over different sizes of domains. Our preliminary results suggest that more aggregated MCS are closely related with an increased contrast of ACRE between the MCS and non-MCS regions, although this relationship is sensitive to the size of the chosen domain.