Spectral, spatial, and temporal sensitivity of correlating MODIS aerosol optical depth with ground-based fine particulate matter (PM<sub>2.5</sub>) across southern Ontario
Bibliographic record
Abstract
This paper evaluates the sensitivity of the aerosol optical depth (AOD) measurements derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) at wavelengths of 0.47, 0.55, and 0.66 µm from both the Terra and Aqua satellites for the estimation of ground-level concentrations of fine particulate matter (PM2.5) in southern Ontario, Canada. The correlation between MODIS AOD and ground-based PM2.5 measurements is compared at different seasons and spatial aggregation levels. The results showed that the MODIS AOD data acquired in early afternoon (from Aqua) seem to have slightly higher agreement with the ground-based measurement of PM2.5 than the late morning Terra data. Moreover, MODIS AOD at 0.47 µm from both satellites had the highest correlation with ground-level PM2.5. More detailed examination suggested that the correlation was stronger in the spring and summer and weaker in the fall and winter. Aqua MODIS AOD appeared to have a better correlation with the average ground-based PM2.5 concentration over 1–3 h than with daily PM2.5. MODIS AOD values aggregated over 3 × 3 pixel groups correlate slightly better with PM2.5 than with the original single centre pixel values.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".