Chicago's heat island and climate change: Bridging the scales via dynamical downscaling

Patrick Conry, Ashish Sharma, Mark J. Potosnak, Laura S. Leo, Edward Bensman, Jessica J. Hellmann, Harindra J.S. Fernando

Research output: Contribution to journalArticlepeer-review


The interaction of global climate change and urban heat islands (UHI) is expected to have far-reaching impacts on the sustainability of the world's rapidly growing urban population centers. Given that a wide range of spatiotemporal scales contributed by meteorological forcing and complex surface heterogeneity complicates UHI, a multimodel nested approach is used in this paper to study climate-change impacts on the Chicago, Illinois, UHI, covering a range of relevant scales. One-way dynamical downscaling is used with a model chain consisting of global climate (Community Atmosphere Model), regional climate (Weather Research and Forecasting Model), and microscale ("ENVI-met") models. Nested mesoscale and microscale models are evaluated against the present-day observations (including a dedicated urban miniature field study), and the results favorably demonstrate the fidelity of the downscaling techniques that were used. A simple building-energy model is developed and used in conjunction with microscale-model output to calculate future energy demands for a building, and a substantial increase (as much as 26% during daytime) is noted for future (~2080) climate. Although winds and lake-breeze circulation for future climate are favorable for reducing energy usage by 7%, the benefits are outweighed by such factors as exacerbated UHI and air temperature. An adverse change in human-comfort indicators is also noted in the future climate, with 92% of the population experiencing thermal discomfort. The model chain that was used has general applicability for evaluating climate-change impacts on city centers and, hence, for urban-sustainability studies.

Original languageEnglish (US)
Pages (from-to)1430-1448
Number of pages19
JournalJournal of Applied Meteorology and Climatology
Issue number7
StatePublished - 2015
Externally publishedYes


  • Climate change
  • Coupled models
  • Heat islands
  • Lake effects

ASJC Scopus subject areas

  • Atmospheric Science


Dive into the research topics of 'Chicago's heat island and climate change: Bridging the scales via dynamical downscaling'. Together they form a unique fingerprint.

Cite this