Assessing the Potential of PlanetScope Satellite Imagery to Estimate Particulate Matter Oxidative Potential
Ian Hough, Loïc Argentier, Ziyang Jiang, Tongshu Zheng, Mike Bergin, David Carlson, Jean-Luc Jaffrezo, Jocelyn Chanussot, Gaëlle Uzu
TL;DR
This study investigates whether high-resolution PlanetScope satellite imagery can be used to estimate particulate matter oxidative potential (OP), measured by OPAA and OPDTT, in Grenoble, France. The authors develop a deep learning pipeline combining a CNN-based image encoder (ResNet50) with a multilayer perceptron, optionally augmented by meteorological data, to predict daily OP at 1 km resolution. Across multiple modeling paradigms—baseline meteorology-only, transfer learning with ImageNet features, fine-tuning, and contrastive learning—the best OPAA performance reached about $R^2 \approx 0.63$ and OPDTT about $R^2 \approx 0.48$, with image-only signals still explaining substantial variance; PM10 predictions followed a similar but weaker pattern. The results suggest a feasible, low-cost approach to broaden OP monitoring, though validation in other regions and larger datasets is needed to confirm generalizability and quantify spatial variability.
Abstract
Oxidative potential (OP), which measures particulate matter's (PM) capacity to induce oxidative stress in the lungs, is increasingly recognized as an indicator of PM toxicity. Since OP is not routinely monitored, it can be challenging to estimate exposure and health impacts. Remote sensing data are commonly used to estimate PM mass concentration, but have never been used to estimate OP. In this study, we evaluate the potential of satellite images to estimate OP as measured by acellular ascorbic acid (OP AA) and dithiothreitol (OP DTT) assays of 24-hour PM10 sampled periodically over five years at three locations around Grenoble, France. We use a deep convolutional neural network to extract features of daily 3 m/pixel PlanetScope satellite images and train a multilayer perceptron to estimate OP at a 1 km spatial resolution based on the image features and common meteorological variables. The model captures more than half of the variation in OP AA and almost half of the variation in OP DTT (test set R2 = 0.62 and 0.48, respectively), with relative mean absolute error (MAE) of about 32%. Using only satellite images, the model still captures about half of the variation in OP AA and one third of the variation in OP DTT (test set R2 = 0.49 and 0.36, respectively) with relative MAE of about 37%. If confirmed in other areas, our approach could represent a low-cost method for expanding the temporal or spatial coverage of OP estimates.
