Table 2.

Statistics of agreement between phenological transition dates derived from PhenoCam imagery (10% seasonal amplitude threshold during “greenness rising” and “greenness falling” phenological phases) and from MODIS satellite remote sensing (onset of greenness, onset of senescence)

PhenoCam ROI Vegetation Type	IGBP Landcover	n	SD (camera DOY)	SD (MODIS DOY)	Pearson’s r	∆ DOY ± SD	Deming regression
							Distance	Slope ± SE	Intercept ± SE
(a) “Greenness rising” phase
AG	12, 14	40	65	58	0.91	−25.1 ± 27.1	18.7	0.89 ± 0.09	−12.8 ± 11.3
	Other	2	12	0		−8.5 ± 12.0
DB	4, 5	284	15	16	0.83	−9.4 ± 9.1	6.4	1.07 ± 0.06	−17.4 ± 6.8
	Other	74	25	29	0.74	−18.0 ± 19.8	13.7	1.22 ± 0.22	−41.6 ± 24.4
EN	1, 5	49	14	15	0.37	26.1 ± 15.9	11.3	1.15 ± 0.36	13.0 ± 31.7
	Other	7	7	18	0.55	16.6 ± 15.3	6.2
GR	10, 12, 14	49	58	60	0.97	−11.4 ± 14.5	10.3	1.03 ± 0.06	−14.7 ± 6.5
	Other	37	54	58	0.90	−6.0 ± 25.0	17.6	1.08 ± 0.12	−12.7 ± 12.1
(b) “Greenness falling” phase
AG	12, 14	40	51	56	0.87	10.6 ± 27.4	19.3	1.11 ± 0.11	−17.9 ± 31.0
	Other	4	16	32	−0.42	29.8 ± 41.5	20.1
DB	4, 5	302	12	17	0.66	15.0 ± 12.9	8.0	1.68 ± 0.18	−182.4 ± 52.7
	Other	75	33	41	0.75	4.9 ± 27.1	18.3	1.31 ± 0.22	−89.5 ± 68.0
EN	1, 5	50	23	17	0.38	−33.4 ± 22.7	14.9	0.49 ± 0.22	134.4 ± 72.3
	Other	7	13	14	0.22	−42.6 ± 16.5	12.8
GR	10, 12, 14	50	43	47	0.84	15.4 ± 25.5	17.9	1.13 ± 0.10	−18.1 ± 26.6
	Other	36	67	64	0.89	16.6 ± 30.2	21.6	0.95 ± 0.06	30.1 ± 14.4

Data reported only for vegetation types for which there were n = 25 or more paired PhenoCam-MODIS observations with similar land cover classification (“apples to apples” comparisons; see text) during both greenness rising and greenness falling phases (see Supplementary Table 2 for the full [vegetation type x IGBP landcover] matrix). Vegetation types are as follows: AG = agricultural; DB = deciduous broadleaf; EN = evergreen needleleaf; GR = grassland. IGBP Landcover classes are defined in Table 1. ROI = region of interest; SD = standard deviation; SE = standard error; DOY = day of year. Deming (orthogonal) regression slope and intercept reported only when the slope is significantly different from 0 at p < 0.05 and n ≥ 10. The Deming regression distance is the RMS (root mean squared) distance, measured perpendicular to the regression line and assuming (n − 2) degrees of freedom.