Contrasting effects of lake breeze and urbanization on heat stress in Chicago metropolitan area

Journal Article · Sat Jan 28 00:00:00 EST 2023 · Urban Climate

DOI:https://doi.org/10.1016/j.uclim.2023.101429· OSTI ID:2329392

Wang, Jiali ^[1]; Qian, Yun ^[2]; Pringle, William ^[1]; Chakraborty, T. C. ^[2]; Hetland, Robert ^[2]; Yang, Zhao ^[2]; Xue, Pengfei ^[3]

---

1. Argonne National Laboratory (ANL), Argonne, IL (United States)
2. Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)
3. Argonne National Laboratory (ANL), Argonne, IL (United States); Michigan Technological Univ., Houghton, MI (United States)

This study used the latest Weather Research and Forecasting (WRF) model coupled with multi -layer urban canopy models to investigate contrasting effects from urbanization and lake breeze on summer heat stress over the Chicago metropolitan area (CMA). Comparisons between the model and in situ observations show that this coupled modeling system better captures urban locations' diurnal pattern of surface air temperature, skin temperature and relative humidity, with root mean square error reduced from 1.58 to 1.80 degrees C to 1.14-1.31 degrees C, 3.11-3.55 degrees C to 1.81-2.21 degrees C, and 10.73-11.35% to 7.84-8.60%, respectively, compared to WRF without coupling the urban canopy models. Two sensitivity experiments were conducted to isolate the influence of lake breeze and urbanization: one replaced the urban land use with cropland over the CMA, and the other filled all of Lake Michigan with cropland. Three different heat stress indices were computed to assess the uncertainties of heat stress response to changes in air temperature, relative humidity, and wind conditions. Results show that, when the lake has the largest cooling effect on air temperature, it also increases the relative humidity the most, and vice versa for urban warming and drying effects. Urbanization intensifies heat stress at night, and extends the heat caution period by up to 4 h over inland urban grids; the lake breeze relieves heat stress during afternoon (when the heat stress is the worst), and shortens the heat caution period by 1-3 h over inland urban grids and 3-4 h over coastal urban grids. In conclusion, the intensification of heat stress over the CMA due to urbanization is more than four times greater than the reduction from the lake breeze in the late afternoon and evening.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL (United States); Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)
• Sponsoring Organization: USDOE; USDOE Office of Science (SC), Biological and Environmental Research (BER). Earth & Environmental Systems Science (EESS)
• Grant/Contract Number: AC02-06CH11357; AC05-76RL01830
• OSTI ID: 2329392
• Alternate ID(s): OSTI ID: 2311005
• Journal Information: Urban Climate, Journal Name: Urban Climate Vol. 48; ISSN 2212-0955
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
Heat stress
Lake breeze
Urbanization