Rapid urbanization induced daily maximum wind speed decline in metropolitan areas: A case study in the Yangtze River Delta (China)

An assessment of observed wind speed and wind power density over China for 1980–2021

“…Since the early 1990s, the EL-type cup anemometer at many stations has been replaced by the EN-type cup anemometer, which provides more accurate and reliable measurement and is easier to install and use. 41,60 We find that the number of breakpoints caused by instrument replacement reached a maximum in 2004, and two weak peaks happened in the early 1990s and early 2010s. For breakpoints caused by station relocation, the mean state of the homogenized NWS series increases at 96 breakpoints while decreases at 17 breakpoints, which indicates that most relocated stations were moved to places with higher wind speed.…”

“…Overall, southern China has more stations with two or more breakpoints than that of northern China, mainly due to the stations with three breakpoints being located along the Yangtze River. It is indicated that the great level of industrialization over there 39,41 induces more relocations of stations and then more breakpoints. To establish the reasons behind each breakpoint, we referred to the metadata provided by NMIC.…”

“…Using 506 stations, the NWS of East China is observed to have a consistent declination at −0.16 m s −1 decade −1 39 . Some studies indicate that urbanization has an important but not dominant role in the regional wind stilling, 40 but its influence is more remarkable in highly urbanized areas, like East China 39,41 . However, some studies also observed a recent break in the “stilling” condition in China 13,28,32–35,42–44 .…”

“…39 Some studies indicate that urbanization has an important but not dominant role in the regional wind stilling, 40 but its influence is more remarkable in highly urbanized areas, like East China. 39,41 However, some studies also observed a recent break in the "stilling" condition in China. 13,28,[32][33][34][35][42][43][44] Based on 2333 stations over China, Zhang and Wang 32 found that the NWS decreases (À0.24 m s À1 decade À1 ) for 1970-2004 and increases (0.02 m s À1 decade À1 ) for 2005-2017.…”

Reduction in reversal of global stilling arising from correction to encoding of calm periods *

“…Monitoring of global near surface winds has shown a decline in the average speeds from the early 1970s to around the mid-2010s, which was termed 'stilling' (Roderick et al 2007, McVicar et al 2012b. Several causes have been proposed for this decline (see Wu et al 2018 for an overview), including an increase in surface roughness induced by the greening of the planet (Vautard et al 2010;Zhu et al 2016) or urbanisation (Chen et al 2020;Zhang et al 2022), natural variability induced by internal decadal ocean-atmosphere oscillations (Zeng et al 2018(Zeng et al , 2019, or errors induced by instrumentation issues (Azorin-Molina et al 2018a).…”