Rural to urban migration and relatively high fertility rates have influenced rapid land cover and land use change (LCLUC) in southern Ghana, which warrants more frequent monitoring. We develop and test approaches for semiautomatically and more frequently identifying the type and date of LCLUC from time series of Landsat ETM+ imagery from 2000 to 2014. Clouds, cloud shadows, and scan line corrector-off create missing data in $\text{ETM}+$ images. Forty-one dates of $\text{ETM}+$ images that partially contain missing data were utilized. The general approach is to conduct a per-pixel supervised classification on each image of a Landsat time series after masking missing data. Spatial, temporal, and logical filters are applied to correct for misclassification and missing data. Each image is classified into three general classes: 1) Built; 2) Natural Vegetation; 3) and Agriculture, with expansion of Built being our main focus. Reference data for Change-to-Built were independently selected from all available high-spatial resolution satellite images (e.g., Quickbird, GeoEye, Worldview, and Google Earth imagery), and the type and beginning time of LCLUC was recorded. Results show that the temporal-filtered product identified both the location and the start of Change-to-Built more precisely and accurately than the nonfiltered and other filtered products. Based on reference data, 40% of the Change-to-Built samples were correctly identified without filtering; whereas, when a temporal filter was applied, 80% were correctly identified with low amounts of false positive Change-to-Built pixels. The temporal-filtered product has the highest temporal precision and accuracy ( $\text{mean time difference} = 2.1 \text{years}$ ) in identifying the start of Change-to-Built.
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