PhenoCam: An evolving, open-source tool to study the temporal and spatial variability of ecosystem-scale phenology Elsevier 11/01/2023 10484325 10.1016/j.agrformet.2023.109751 Agricultural and Forest Meteorology 0168-1923 342 C Andrew D. Richardson
I nt r o d u cti o n 4 P h e n ol o g y, t h e st u d y of s e as o n al r h yt

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3 Ass ess m e nt of s at ellit e r e m ot e s e nsi n g pr o d u cts 4 7 Wit h o ut a d o u bt, o n e of t h e ar e as i n w hi c h t h e P h e n o C a m N et w or k h as m a d e t h e gr e at est 4 7 c o ntri b uti o n t o e n vir o n m e nt al a n d e c ol o gi c al s ci e n c e is t h e ass ess m e nt of s at ellit e r e m ot e s e nsi n g 4 7 pr o d u cts fr o m diff er e nt pl atf or ms ( T a bl e 2). It is c o m m o nl y r e c o g ni z e d t h at t h e i n h er e nt 4 7 diff er e n c es b et w e e n G c c a n d N D VI, as w ell as t h e o bli q u e vi e w of P h e n o C a ms a n d t h e n a dir 4 7 vi e w of s at ellit es, pr e cl u d e tr u e " v ali d ati o n, " b ut t h e o v er all q u alit y of t h e P h e n o C a m d at a h as b o u n d o n t h e u n c ert ai nt y i n s at ellit e pr o d u cts (Z h a n g et al., 2 0 1 8) . F urt h er m or e, vis u al 4 8 i nt er pr et ati o n of t h e P h e n o C a m i m a g er y its elf c a n pr o vi
"s u bst a nti al v ari a bilit y wit hi n t h e gr o wi n g s e as o n [i n t h e i n di c es d eri v e d fr o m M E RI S] t h at is 5 0 u nr el at e d t o v e g et ati o n d y n a mi cs " -p oi nti n g t o t h e n e e d f or " m or e ri g or o us at m os p h eri
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C o n cl usi o n s 7 9 T h e fi el d of p h e n ol o gi c al r es e ar c h h as c h a n g e d e n or m o usl y o v er t h e 6 0 y hist or y of 7 9 A F M. T h e p a c e of c h a n g e h as a c c el er at e d gr e atl y i n j ust t h e l ast t w o d e c a d es as cli m at
M u c h of t h e i m p ort a nt 8 0 p h e n o c a m lit er at ur e h as b e e n p u blis h e d i n A F M, a n d i n t his r e vi e w I h a v e i d e ntifi e d 5 k e y 8 0 t h e m es of t his r es e ar c h a n d hi g hli g ht e d t h e A F M p a p ers t h at h a v e c o ntri b ut e d t o n e w 8 0 u n d erst a n di n g . I h a v e als o i d e ntifi e d k e y ar e as w h er e I t hi n k w e c a n e x p e ct t o s e e e x citi n g n e w 8 0 a d v a n c e m e nts i n p h e n o c a m -dri v e n r es e ar c h . G i v e n t h e si z e of t h e
Fi n all y, I t hi n k o n e r e as o n t h e P h e n o C a m N et w or k h as b e e n s o s u c c essf ul is 8 1 t h at h u m a n c o n n e cti o ns h a v e r es ult e d i n a n or g a ni c, gr assr o ots n et w or k t h at is r o ot e d i n s h ar e d 8 1 v al u es of tr ust, r es p e ct, a n d c oll a b or ati o n. F or m e, it h as b e e n b ot h r e m ar k a bl e a n d h u m bli n g t o 8 1 s e e h o w t h es e eff orts h a v e l e d t o a c oll a b or ati v e, c o nti n e nt al -s c al e p h e n ol o gi c al o bs er v at or y 8 1 n et w or k t h at is s o m u c h m or e t h a n t h e s u m of t h e i m a g es a n d d at a pr o d u cts i n o ur d at a ar c hi v e -8 1 a n d h as e n a bl e d t h e a m a zi n g a n d di v ers e s ci e ntifi c r es e ar c h t h at I h a v e r e vi e w e d h er e.
Mi c h a el F ell, a n d K eit h B all o u . M y h u n dr e ds of P h e n o C a m sit e c oll a b or at ors als o d es er v e 8 3 a c k n o wl e d g m e nt as t h eir e nt h usi as m h as h el p e d t o c arr y t h e N et w or k f or w ar d . 8 3 T h e d e v el o p m e nt of P h e n o C a m h as b e e n f u n d e d b y t h e N ort h e ast er n St at es R es e ar c h
Q u a ntit ati v e p h e n ol o gi c al o bs er v ati o ns of a mi x e d b e e c h f or est i n n ort h er n 8 5 S witz erl a n d wit h di git al p h ot o gr a p h y. J G e o p h ys R es

V az q u ez -L ul e, A., V ar g as, R., V áz q u ez -L ul e, A., V ar g as, R. Bi ol 1 5, 2 3 3 5 -2 3 5 9. htt ps:// d oi. or g/ 1 0. 1 1 1 1/j. 1 3 6 5 -2 4 8 6. 2 0 0 9. 0 1 9 1 0. x 1 2 8 A S A E 3 8, 2 5 9 -2 6 9. htt ps:// d oi. or g/ 1 0. 1 3 0 3 1/ 2 0 1 3. 2 7 8 3 8 1 2 9 W u, C., P e n g, J., Ci ais, P., P e ñ u el as, J., W a n g, H., B e g u erí a, S., A n dr e w Bl a c k, T., J ass al, R. S., 1 2 9 Z h a n g, X., Y u a n, W., Li a n g, E., W a n g, X., H u a, H., Li u, R., J u, W., F u, Y. H., G e, Q., 2 0 2 2.

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