Extended Data Table 1 The November to March Maxar satellite images considered and the number selected for our analysis by UTM zone

From: Sub-continental-scale carbon stocks of individual trees in African drylands

  1. a, We started with 326,523 candidate images and selected 94,502 for processing for the area of 9.5° N to 24° N latitude from the Atlantic Ocean to the Red Sea for the months of November to March. 87% of data selected for processing were acquired from 2010 to 2020 and 94% of the selected satellite images were from November to January. Each image had a panchromatic and NDVI component that was used to identify trees with canopy area 3 m2 or greater in the early dry season. b, Specific satellite information for the four Maxar satellites used in our study includes the period of operation or the launch date, the nadir swath width, the nadir panchromatic spatial resolution and the spectral regions available. The relative geolocation accuracies of the four Maxar satellites used in our study are expressed in circular error probabilities or CE90 units, meaning that a given point will be within a specific radius 90% of the time, and in terms of RMSEs, which are one standard deviation of the residuals or distance-prediction errors. Our satellite data were resampled to a 50-cm spatial resolution for the panchromatic band and that band was used to panchromatically sharpen the NDVI to 50 cm. See also https://resources.maxar.com/data-sheets/quickbird; https://resources.maxar.com/data-sheets/geoeye-1; https://resources.maxar.com/data-sheets/worldview-2; and https://resources.maxar.com/data-sheets/worldview-3.
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