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(i) come from the same sensor or product, (ii) have equivalent native spatial resolutions and (iii)
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represent similar parts of the electromagnetic spectrum (for Sentinel-2 channel groups). We group
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the input data into the following channel groups:
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•Sentinel-1 : The VV and VH bands from the Sentinel-1 sensor
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•Sentinel-2 RGB : The B2, B3 and B4 bands from the Sentinel-2 sensor
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•Sentinel-2 Red Edge : The B5, B6 and B7 bands from the Sentinel-2 sensor
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•Sentinel-2 Near Infra Red (10m) : The B8 band from the Sentinel-2 sensor
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•Sentinel-2 Near Infra Red (20m) : The B8A band from the Sentinel-2 sensor
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•Sentinel-2 Short Wave Infra Red : The B11 and B12 bands from the Sentinel-2 sensor
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•NDVI : The normalized difference vegetation index, calculated from the Sentinel-2 B4 and B8
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bands.
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•ERA5 Climatology : Precipitation and temperature at 2m from the ERA5 Climate Reanalysis
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product
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•Topography : The elevation and slope of a pixel, calculated by the SRTM’s DEM
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•Location : The cartesian coordinates of a pixel, computed from the pixel’s latitude and longitude
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17
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Table 10: Full results for regression tasks from Table 3, including standard error computed from three
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runs.
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Fuel Moisture Algae Blooms Mean difference
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Linear Regression 28.20 0.850 0%
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Random Forest 23.84±0.42 1.249±0.02 15.7%
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MOSAIKS-1D RF 28.75±0.15 0 .972±0.01 8.15%
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Presto FT(random init.) 26.07±0.52 0 .955±0.05 2.40%
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Presto FT 25.28±0.30 0 .815±0.03 −7.24%
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Presto RF 25.98±0.66 0 .884±0.01 −1.94%
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A.2 FLOP calculations
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We use the thop library ( https://github.com/Lyken17/pytorch-OpCounter ) to calculate the
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FLOPs required to encode a EuroSAT image (as plotted in Table 5(b)). For the SatMAE, ScaleMAE
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and ConvMAE models, all images were resized to 224×224, so the FLOPs required to encode
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an image is independent of resolution. For Presto, we computed the FLOPs required to encode a
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single pixel and multiplied this by the number of pixels in an image at each resolution (e.g. the
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“64” resolution has 64×64pixels, so we multiply the FLOPs required to encode a single pixel by
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64×64 = 4096 ). The FLOPs calculated by the thop library are recorded in Table 9.
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A.3 Baselines
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In addition to task-specific baselines, we benchmark Presto against:
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•Random Forests : Random forests are powerful baselines in remote sensing as they they remain
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competitive with state-of-the-art methods (Pelletier et al., 2019; Kerner et al., 2020). Tree-based
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methods, especially random forests, are commonly deployed in large-scale machine learning for
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remote sensing applications (Hansen et al., 2013; Van Tricht, 2021; Di Tommaso et al., 2022).
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•MOSAIKS-1D : We adapt MOSAIKS (Rolf et al., 2021) for timeseries data. MOSAIKS-1D uses
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patches from the pre-training dataset and convolves over the temporal dimension instead of the
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spatial dimension. We benchmark MOSAIKS-1D on all timeseries evaluation tasks. Because this
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does not work for categorical inputs, we exclude Dynamic World. As with Presto, we use the
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output features with random forests (MOSAIKS-1D RF) and with regressions (MOSAIKS-1D R).
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A.4 Downstream Results
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We include complete results for the evaluation tasks. These include error bars, as well as additional
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results reported for the CropHarvest (Table 12 and Figure 3), regression tasks (Table 10), EuroSAT
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(Tables 11, 13 and 14), TreeSatAI (Table 15) and Sen2-Agri 100(Table 16) datasets.
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We run all downstream classifiers with 3 seeds ( 0,42,84), with the exception of the kNN classifiers
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and the linear regression (which are deterministic). In the tables in the main paper (Tables 2, 4, 6 and
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3) we report the average of these runs; the standard error is reported in Tables 12,15, 16 and 10.
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•Presto as a feature extractor : When used as a feature extractor, a random forest, regression of
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K-nearest-neighbours classifier is trained on Presto’s output embeddings. In this case, we use
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scikit-learn models with the default hyperparameters. For the CropHarvest tasks, the class labels
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are extremely imbalanced; we therefore set class_weight equal to balanced for those tasks, for
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both Presto and MOSAIKS-1D.
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•Fine-tuning Presto : When fine-tuning Presto, we use the same hyperparameters across all tasks:
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an AdamW optimizer with a learning rate of 3e-4 and weight decay of 0.05.
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As discussed in Section 5.2, we obtain per-image predictions using Presto by computing a mean and
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standard deviation of Presto’s output pixels, and passing a concatenation of these two vectors to a
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downstream classifier. This is illustrated in Figure 4.
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18
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Table 11: Accuracy results for pre-trained and from-scratch Presto when fine-tuned on EuroSat, at
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varying resolutions. We hypothesize that the drop in performance for the full resolution (64) RGB
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input is due to the model construction; the model outputs for all pixels in the image (4,096 pixels
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for the full resolution) are aggregated and passed to a linear layer for classification, yielding a noisy
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gradient signal.
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Resolution 2 4 8 16 32 64
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random init.RGB0.703±0.005 0 .684±0.032 0 .694±0.013 0 .739±0.004 0 .750±0.018 0 .745±0.009
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pre-trained 0.792±0.010 0 .837±0.006 0 .847±0.016 0 .865±0.006 0 .872±0.002 0 .849±0.004
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random init.MS0.837±0.014 0 .884±0.010 0 .895±0.006 0 .907±0.13 0 .924±0.005 0 .924±0.003
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pre-trained 0.898±0.005 0 .925±0.004 0 .939±0.000 0 .950±0.002 0 .958±0.001 0 .953±0.004
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Table 12: Additional results for the CropHarvest task. In addition to the F1 scores reported in the
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main paper, we report AUC ROC scores, with standard error bars computed with three runs.
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Model Kenya Brazil Togo Mean
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F1Random Forest 0.559±0.003 0 .000±0.000 0 .756±0.002 0.441
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MOSAIKS-1D R 0.790±0.027 0 .746±0.084 0 .679±0.024 0.738
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TIML 0.838±0.000 0 .835±0.012 0 .732±0.002 0 .802
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Presto R 0.816±0.000 0.891±0.000 0 .798±0.000 0.835
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no DW 0.861±0.000 0.888±0.000 0 .760±0.000 0.836
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AUC ROCRandom Forest 0.578±0.006 0 .941±0.004 0 .892±0.001 0.803
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MOSAIKS-1D R 0.693±0.036 0 .890±0.038 0 .836±0.005 0.806
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TIML 0.794±0.003 0 .988±0.001 0 .890±0.000 0 .890
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Presto R 0.834±0.000 0.997±0.000 0 .921±0.000 0.917
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no DW 0.863±0.000 0.989±0.000 0 .912±0.000 0.921
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A.5 Disentangling the effect of pre-training
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To understand the effect of pre-training Presto, we fine-tune Presto and train it from scratch on
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EuroSat (Table 5), the regression tasks (Table 3 in the main paper) and TreeSatAI (Table 15). We
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omit the CropHarvest dataset because it was expressly designed as a few-shot-learning dataset. Its
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small size makes the construction of validation sets with which to control the finetuning (e.g. with
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early stopping) challenging.
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Overall, we find a consistent and significant improvement from the use of pre-trained Presto compared
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to a randomly initialized version of the model. For the EuroSat task, pre-training consistently delivers
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an incresse in accuracy score >0.1(representing increases in accuracy of up to 25%). This effect is
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consistent with what we observe on the TreeSatAI dataset for S2 data and on the regression tasks
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(where pre-training reduces RMSE by to 15% on the algae blooms task). For the TreeSatAI dataset
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with S1 data, pre-training penalizes the model compared to random initialization - we hypothesize
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that this is due to the difference in input (a single timestep and single channel group image) relative
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to the pre-training data. The benefit of pre-training effect is especially pronounced on the S2-Agri 100
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dataset; we hypothesize this is due to the small training set size.
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