Table 3. Year to year variability (mean standard deviation ± 1 SD) for the start and end, and duration of the season for the three study periods.

		standard deviation for each period
		(n = 77 scenarios)
Region	Variable	(1971–2000)	(2046–2065)	(2081–2100)
BSL	Start (J.d)	12.3 ± 2.4	13.2 ± 2.9	14.4 ± 3.5
	End (J.d)	7.4 ± 1.6	7.7 ± 1.9	8.8 ± 2.6
	Length (d)	9.6 ± 1.9	11.2 ± 2.9	12.4 ± 3.3
CTS	Start (J.d)	14.3 ± 2.6	14.9 ± 3.1	15.5 ± 3.4
	End (J.d)	7.8 ± 1.8	8.4 ± 2.0	9.5 ± 2.6
	Length (d)	11.3 ± 2.0	13.4 ± 3.2	13.8 ± 3.7
BEA	Start (J.d)	16.4 ± 2.0	16.4 ± 3.1	16.8 ± 3.0
	End (J.d)	8.5 ± 1.6	9.4 ± 2.4	10.7 ± 2.9
	Length (d)	13.4 ± 2.2	15.2 ± 2.9	15.6 ± 3.7
QUE	Start (J.d)	12.6 ± 2.5	13.2 ± 2.9	14.4 ± 3.3
	End (J.d)	7.4 ± 1.6	8.1 ± 2.0	9.0 ± 2.5
	Length (d)	9.9 ± 2.2	12.0 ± 3.1	12.9 ± 3.3
MAU	Start (J.d)	12.0 ± 1.9	12.8 ± 2.9	14.0 ± 3.5
	End (J.d)	7.6 ± 1.5	8.4 ± 1.9	8.9 ± 2.1
	Length (d)	9.6 ± 1.7	11.6 ± 2.8	12.4 ± 3.3
LAN	Start (J.d)	13.9 ± 2.0	14.7 ± 3.0	15.3 ± 3.5
	End (J.d)	8.1 ± 1.4	8.9 ± 2.1	9.5 ± 2.4
	Length (d)	11.1 ± 2.2	13.2 ± 2.8	13.3 ± 3.3
EST	Start (J.d)	17.7 ± 2.4	17.0 ± 2.9	16.2 ± 2.6
	End (J.d)	9.3 ± 2.1	9.9 ± 2.4	11.1 ± 2.3
	Length (d)	14.9 ± 2.3	15.7 ± 2.8	15.3 ± 3.2
LAU	Start (J.d)	14.0 ± 1.9	15.4 ± 3.0	16.1 ± 2.9
	End (J.d)	8.2 ± 1.6	9.0 ± 2.1	9.7 ± 2.3
	Length (d)	11.6 ± 2.0	14.0 ± 2.9	13.8 ± 3.1
CDQ	Start (J.d)	16.8 ± 2.0	16.8 ± 3.0	16.6 ± 2.7
	End (J.d)	8.2 ± 1.5	8.9 ± 1.9	10.3 ± 3.0
	Length (d)	13.8 ± 2.0	15.5 ± 3.1	15.2 ± 3.5
STY	Start (J.d)	17.8 ± 1.7	16.5 ± 3.0	15.5 ± 3.0
	End (J.d)	8.9 ± 1.9	9.6 ± 2.2	10.8 ± 2.5
	Length (d)	15.0 ± 2.0	15.7 ± 2.8	14.9 ± 3.3
VAL	Start (J.d)	18.6 ± 1.9	16.7 ± 2.9	15.6 ± 2.9
	End (J.d)	8.9 ± 1.7	9.8 ± 2.3	10.6 ± 2.5
	Length (d)	15.7 ± 1.8	15.8 ± 2.7	15.1 ± 3.4

The standard deviation reported is indicative of uncertainty between the 77 climate scenarios. Please see Fig 1 for region acronyms.