Our Approach: We focus our efforts to make use of the historical archive of 30m Landsat imagery by coupling it with moderate resolution sensors such as MODIS (Moderate resolution Imaging Spectroradiometer) to generate products with improved spatial and temporal resolutions and to make use of the additional channels for cloud clearing, atmospheric correction, and vegetation and ocean dynamics.
Introduction
Surface albedo has been recognized by the international bodies GCOS (Global Climate Observing System), GTOS (Global Terrestrial Observing System) and GOOS (Global Ocean Observing System) as an essential climate variable (ECV) crucial for accurate modeling and monitoring of the Earth’s radiative and biophysical regimes (GCOS, 2004; Schaaf et al., 2009). However, albedo varies temporally and spatially as a result of ecosystem functioning and surface heterogeneity. Therefore, consistent and accurate albedo data sets are essential for investigating the sensitivity of ecosystems to various component surface covers. Also, these data sets show how surface reflectance changes due to disturbances within ecosystems, such as in fragmented forests, intensively cropped areas, and degrading seagrass beds in coastal areas.
Given the variability of global albedo, remotely sensed data offer the only viable method of capturing the heterogeneity of surface reflectance in ecosystems. Over the past decade a number of multi-spectral satellite sensors have been used to capture the measures of global albedo on gridded resolutions of 250m-1km. While these products provide crucial inputs for climate and atmospheric prediction models, these resolutions are still quite coarse to monitor regional environmental impacts.
Our surface reflectance product draws from the spatial and temporal resolution Landsat satellites, yielding the finer details of albedo with more observations than were previously possible. By generating surface reflectance at the scale of a Landsat pixel, we enable the capturing the details of environmental change due to urban conversion, agricultural practices, forest management regimes, disturbances from pests, fire, and human activities, and the vulnerabilities of coastal, estuary and nearshore environments.
Professor Crystal Schaaf’s Lab
School for the Environment University of Massachusetts Boston 100 Morrissey Blvd.
