The meso scale as a frontier in interdisciplinary modeling of sustainability from local to global scales

Abstract

Achieving sustainable development requires understanding how human behavior and the environment interact across spatial scales. In particular, knowing how to manage tradeoffs between the environment and the economy, or between one spatial scale and another, necessitates a modeling approach that allows these different components to interact. Existing integrated local and global analyses provide key insights, but often fail to capture “meso-scale” phenomena that operate at scales between the local and the global, leading to erroneous predictions and a constrained scope of analysis. Meso-scale phenomena are difficult to model because of their complexity and computational challenges, where adding additional scales can increase model run-time exponentially. These additions, however, are necessary to make models that include sufficient detail for policy-makers to assess tradeoffs. Here, we synthesize research that explicitly includes meso-scale phenomena and assess where further efforts might be fruitful in improving our predictions and expanding the scope of questions that sustainability science can answer. We emphasize five categories of models relevant to sustainability science, including biophysical models, integrated assessment models, land-use change models, earth-economy models and spatial downscaling models. We outline the technical and methodological challenges present in these areas of research and discuss seven directions for future research that will improve coverage of meso-scale effects. Additionally, we provide a specific worked example that shows the challenges present, and possible solutions, for modeling meso-scale phenomena in integrated earth-economy models.

Focus on global–local–global analysis of sustainability

“…Increased complexity can outstrip data and modeling capabilities, slow down research, make results more difficult to understand and interpret, and complicate effective communication with decision-makers and other users of the analyses. As Johnson et al (2023b) illustrate in their figure 2, a limited computational budget requires making trade-offs about where to opt for more versus less detail, e.g. in spatial resolution, number of economic sectors, or biophysical processes.…”

“…Banerjee et al (2022) use the IEEM Platform that integrates economic, land use, and ecosystem service models, to analyze whether the Amazon rainforest will likely cross a tipping point. The papers by Johnson et al (2023b), andCisneros-Pineda et al (2023), though focused mainly on issues of modeling the meso-scale, and linkages across local-global and global-local scales, also illustrate the importance of linking economic, land use, and biophysical models. These papers discuss the development of an 'Earth-Economy model' that links the GTAP general equilibrium model of the economy with the InVEST model of ecosystem services showing how economic drivers can lead to ecosystem change, which changes the flow of ecosystem services, and how this then affects macroeconomic performance.…”

“…In addressing this challenge, local, meso, and global scale perspectives are required (figure 1). The local scale refers to the socio-economic and environmental conditions in the neighborhood of individual agents, e.g., landowners with their surrounding environment (Johnson et al 2023b). The meso-scale can be thought of as regionalscale, with regions varying from small watersheds to entire river basins (e.g.…”

Accounting for spatial economic interactions at local and meso scales in integrated assessment model (IAM) frameworks: challenges and recent progress

“…landowners, with surrounding natural systems (Johnson et al 2023). The meso scale is the mediating layer of processes, systems, and institutions, including markets, that connect local scale phenomena to larger, global scale systems and vice versa (Johnson et al 2023). Spatial economic interactions, i.e.…”

“…In this context, the local scale can be thought of as those economic and environmental phenomena that manifest at scales of 1 km or less and involve the decisions and interactions of individual agents, e.g. landowners, with surrounding natural systems (Johnson et al 2023). The meso scale is the mediating layer of processes, systems, and institutions, including markets, that connect local scale phenomena to larger, global scale systems and vice versa (Johnson et al 2023).…”