Table 2 Results of mixed-effects models that compare the IPCC Tier 1 default to the EO-based mean aboveground biomass density (AGBD), while filtering the variance associated with each estimate in both datasets. Results are provided for all forest classes, and separately per continent, per forest status/condition and per Geographic Ecological Zone (GEZ).

From: Intergovernmental Panel on Climate Change (IPCC) Tier 1 forest biomass estimates from Earth Observation

Group

N

GEDI and ICESat-2

ESA CCI

All classes

 

\(\widehat{{\boldsymbol{\alpha }}}\)

SE[\(\widehat{{\boldsymbol{\alpha }}}\)]

t

p

\(\widehat{{\boldsymbol{\alpha }}}\)

SE[\(\widehat{{\boldsymbol{\alpha }}}\)]

t

p

140

−1.66

4.46

−0.37

0.71

−10.29

4.77

−2.16

0.03*

Continent

 

\(\widehat{{\boldsymbol{\alpha }}}\)

SE[\(\widehat{{\boldsymbol{\alpha }}}\)]

t

p

\(\widehat{{\boldsymbol{\alpha }}}\)

SE[\(\widehat{{\boldsymbol{\alpha }}}\)]

t

p

Africa

26

−4.41

7.77

−0.57

0.575

−22.04

6.19

−3.56

0.002*

Asia

30

10.09

10.12

1.00

0.327

−31.94

11.23

−2.84

0.008*

Europe

9

15.88

9.07

1.75

0.118

22.66

10.22

2.22

0.057

North America

39

5.29

6.93

0.76

0.450

−9.35

8.03

−1.16

0.252

Oceania

3

−55.02

60.18

−0.91

0.457

16.34

42.05

0.39

0.735

South America

33

−1.19

8.82

−0.13

0.894

22.70

7.85

2.89

0.007*

Forest status/condition

 

\(\widehat{{\boldsymbol{\alpha }}}\)

SE[\(\widehat{{\boldsymbol{\alpha }}}\)]

t

p

\(\widehat{{\boldsymbol{\alpha }}}\)

SE[\(\widehat{{\boldsymbol{\alpha }}}\)]

t

p

Primary

40

−3.46

11.58

−0.30

0.767

−11.29

9.83

−1.15

0.258

Old secondary

50

−5.97

5.62

−1.06

0.294

−22.83

8.15

−2.80

0.007*

Young secondary

50

12.08

4.95

2.44

0.018*

−0.04

7.06

−0.01

0.996

Geographic Ecological Zones

 

\(\widehat{{\boldsymbol{\alpha }}}\)

SE[\(\widehat{\alpha }\)]

t

p

\(\widehat{{\boldsymbol{\alpha }}}\)

SE[\(\widehat{{\boldsymbol{\alpha }}}\)]

t

p

Tropical dry forest

12

−9.81

14.86

−0.66

0.523

−19.61

13.41

−1.46

0.172

Tropical moist deciduous forest

12

−13.61

14.22

−0.96

0.359

−15.25

13.76

−1.11

0.292

Tropical mountain system

12

25.00

25.92

0.96

0.355

−11.99

22.92

−0.52

0.611

Tropical rainforest

12

−0.36

15.13

−0.02

0.982

−10.46

25.04

−0.42

0.684

ropical shrubland

11

25.39

13.53

1.88

0.090

4.12

12.47

0.33

0.748

Subtropical dry forest

12

−1.90

11.26

−0.17

0.869

−22.20

9.51

−2.34

0.039*

Subtropical humid forest

12

−0.85

11.11

−0.08

0.940

−5.00

9.79

−0.51

0.619

Subtropical mountain system

12

15.30

12.33

1.24

0.241

−18.33

16.83

−1.09

0.299

Subtropical steppe

11

13.91

10.24

1.36

0.204

−16.25

7.65

−2.12

0.060

Temperate continental forest

7

−2.24

9.84

-0.23

0.828

−36.86

7.94

−4.64

0.004*

Temperate mountain system

8

−32.91

30.20

−1.09

0.312

−22.75

33.13

−0.69

0.514

Temperate oceanic forest

10

−49.60

33.14

−1.50

0.169

0.08

26.74

0.00

0.998

Temperate steppe

4

−12.23

56.70

−0.22

0.843

−4.63

53.50

−0.09

0.937

Boreal tundra woodland

3

−47.63

22.87

−2.08

0.173

−22.68

22.49

−1.01

0.419

  1. N is the number of samples, α is the estimate of the intercept, and SE is the standard error of α (Eq. (9)). Values of p < 0.05* indicate a significant systematic difference between IPCC values and EO-based estimates.