EAA: Eastern Asia; SAA: South Asia; SEA: Southeast Asia; EUR: Europe;
ENAM: Eastern North America; WNAM: Western North America; SAM: South
America; NAME: North Africa and the Middle East; SAF: South Africa; OCE:
Oceania.
On a global scale, the ART-GCT-GEE model demonstrates superior overall
accuracy, attaining a high CV-R value of 0.902, with the median bias
approaching zero and maintaining average RMSE and MAE values of 0.086
and 0.050, respectively. Overall, approximately 84.38% and 52.11% of
the Landsat AOD retrievals conform to the EE and GCOS criteria (Figure
4a). Our model also demonstrates a strong capability to predict AOD at
new locations in the absence of ground monitors (Figure 4b) and on dates
when ground measurements are unavailable (Figure 4c), as evidenced by
average CV-R values of 0.826 and 0.871, MAE values of 0.066 and 0.057,
and RMSE values of 0.111 and 0.097, respectively. Notably, around
74.71% (41.68%) and 80.43% (47.34%) of the AOD predictions align
with the EE and GCOS anticipated deviations, respectively. Furthermore,
our proposed model also exhibits great performance at regional scales
(Tables 1, S4, and S5), especially in East and South Asia (e.g., CV-R =
0.83–0.93, \(f_{\text{EE}}\) = 67–84%) and South America (e.g., R =
0.82–0.90, \(f_{\text{EE}}\) = 81–89%).