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The Universal Thermal Climate Index (UTCI) has been linked to outdoor activity patterns and used to evaluate the effectiveness of urban interventions to improve thermal comfort. This study investigates how simulating the urban environment at increasing levels of physical accuracy impacts UTCI values along three cycling routes in Cambridge, Massachusetts. Baseline UTCI values are estimated using a local weather file, and the following increments in physical accuracy are considered: wind-scaling, shading from buildings, shading and cooling from trees, computational fluid dynamics simulations for wind speeds, and simulated surface temperatures. With bike ridership data from Bluebikes, Boston's bike-sharing program, the relationship between bike ridership patterns and UTCI values along each route is studied. Supervised machine learning models are applied to predict bike ridership based on UTCI and other predictors. UTCI simulation results show that incorporating the various increments of accuracy influences hourly UTCI values at urban areas and exposed areas differently. Incorporating local wind speeds is especially impactful for urban areas. The statistical models trained to predict hourly bike trip counts based on UTCI and other demand and weather predictors achieved a root-mean-squared error of 1.06 trips. 47% of predictions were correct, and an additional 42% of predictions were off by 1 trip. This study demonstrates the importance of spatial refinement in simulating UTCI, and motivates future research into efficient simulation methods or rules-of-thumb for deriving spatial-temporal UTCI values. Future work into building a robust predictive model would motivate the design of thermally comfortable environments for human-powered transportation in cities. [Display omitted] [ABSTRACT FROM AUTHOR]

Highlights • Ensemble baseline development to simulate a range of future building energy scenarios. • Framework for rapid-response assessment of energy drivers for hundreds of buildings. • Procedures for campuses to track their energy policy effectiveness on an ongoing basis. • Proof-of-concept implementation for campus of Massachusetts Institute of Technology. Abstract Physics-based building energy models, once calibrated to historic energy data, are increasingly used to explore energy efficiency retrofits. When utilized for large building portfolios, such as university campuses, these calibrated models require substantial initial effort to develop, but are then typically only used once for analyzing potential building upgrades and estimating carbon reduction opportunities. This paper presents a continuous energy performance planning and tracking system for a university campus that automatically updates and compares measured against simulated building energy use for a hundred campus buildings. The system archives historic data, enables exploration of potential upgrade scenarios, and allows for the documentation of energy retrofits to individual buildings. The objectives of this tracking system are to support facility managers to ensure that their buildings are performing as intended, financial administrators to quantify potential energy savings and payback times of building upgrades and the overall university community to track campus-wide carbon emissions from buildings vis-à-vis previously defined reduction targets. A proof-of-concept implementation is presented for the authors' campus in Cambridge, Massachusetts. [ABSTRACT FROM AUTHOR]