Table 2.

Spearman correlations between main air gaseous pollutants and climate variables with COVID-19 daily new cases (DNC) and COVID-19 daily new deaths (DND)in Madrid metropolitan region during the four COVID-19 waves.

Factors	1st COVID-19 wave		COVID-19 Under Heat wave		2nd COVID-19 wave		3rd COVID-19 wave		4th COVID-19 wave
	1 March 2020–30 June 2020		1 July 2020–9 August 2020		10 August 2020–30 November 2020		1 December 2020–28 February 2021		1 March 2021–30 June 2021
	DNC	DND	DNC	DND	DNC	DND	DNC	DND	DNC	DND
O3 (μg/m3)	r = -0.35 p < 0.01	r = -0.25 p < 0.01	−0.19 p > 0.05	−0.04 p > 0.05	r = 0.45 p < 0.01	r = -0.59 p < 0.01	r = -0.37 p < 0.01	r = -0.16 p < 0.01	r = -0.17 p < 0.01	R = -0.35 p < 0.01
NO2 (μg/m3)	r = 0.10 p > 0.05	r = 0.40 p < 0.01	0.43 p < 0.01	−0.28 p > 0.05	r = 0.10 p > 0.05	r = 0.55 p < 0.01	r = 0.24 p < 0.05	r = 0.12 p > 0.05	r = 0.55 p < 0.01	r = 0.49 p < 0.01
T (oC)	r = -0.55 p < 0.01	r = -0.58 p < 0.01	0.13 p > 0.05	−0.32 p < 0.01	r = 0.49 p < 0.01	r = -0.70 p < 0.01	r = -0.25 p < 0.05	r = 0.46 p < 0.01	r = -0.42 p < 0.01	r = -0.65 p < 0.01
RH (%)	r = 0.52 p < 0.01	r = 0.65 p < 0.01	0.14 p > 0.05	0.16 p > 0.05	r = -0.40 p < 0.01	r = 0.69 p > 0.05	r = 0.36 p < 0.01	r = 0.25 p < 0.05	r = 0.28 p < 0.01	r = 0.32 p < 0.01
w (km/h)	r = -0.45 p < 0.01	r = -0.51 p < 0.01	−0.28 p > 0.05	0.18 p > 0.05	r = 0.18 p < 0.01	r = -0.31 p < 0.01	r = -0.21 p = 0.05	r = 0.05 p > 0.05	r = -0.26 p < 0.01	r = -0.29 p < 0.01
SI(W/m2)	r = -0.47 p < 0.01	r = -0.45 p < 0.01	−0.54 p < 0.01	0.05 p > 0.05	r = 0.46 p < 0.01	r = -0.80 p < 0.01	r = 0.12 p = 0.2 > 0.05	r = 0.53 p < 0.01	r = -0.34 p < 0.01	r = -0.69 p < 0.01
PBL (m)	r = -0.39 p < 0.01	r = -0.39 p < 0.01	0.26 p > 0.05	−0.11 p > 0.05	r = 0.49 p < 0.01	r = -0.66 p < 0.01	r = -0.32 p < 0.01	r = -0.02 p > 0.05	r = -0.35 p < 0.01	r = -0.56 p < 0.01