Global overview of cloud-, snow-, and shade-free Landsat (1982-2023) and Sentinel-2 (2015-2023) data

Landsat and Sentinel-2 acquisitions are among the most frequently used medium-resolution (i.e., 10-30 m) optical data. The data are extensively used in terrestrial vegetation applications, including but not limited to, land cover and land use mapping, vegetation condition and phenology monitoring, and disturbance and change mapping. While the Landsat archives alone provide over 40 years, and counting, of continuous and consistent observations, since mid-2015 Sentinel-2 has enabled a revisit frequency of up to 2-days. Although the spatio-temporal availability of both data archives is well-known at the scene level, information on the actual availability of usable (i.e., cloud-, snow-, and shade-free) observations at the pixel level needs to be explored for each study to ensure correct parametrization of used algorithms, thus robustness of subsequent analyses. However, a priori data exploration is time and resource‑consuming, thus is rarely performed. As a result, the spatio-temporal heter..., We based our analyses on freely and openly accessible Landsat and Sentinel-2 data archives available in Google Earth Engine (Gorelick et al., 2017). We used all Landsat surface reflectance Level 2, Tier 1, Collection 2 scenes acquired with the Thematic Mapper (TM) (Earth Resources Observation And Science (EROS) Center, 1982), Enhanced Thematic Mapper (ETM+) (Earth Resources Observation And Science (EROS) Center, 1999), and Operational Land Imager (OLI) (Earth Resources Observation And Science (EROS) Center, 2013) scanners between 22nd August 1982 and 31st December 2023, and Sentinel-2 TOA reflectance Level-1C scenes (pre‑Collection-1 (European Space Agency, 2015, 2021) and Collection-1 (European Space Agency, 2022)) acquired with the MultiSpectral Instrument (MSI) between 23rd June 2015 and 31st December 2023.
We implemented a conservative pixel-quality screening to identify cloud-, snow-, and shade-free land pixels. For the Landsat time series, we relied on the inherent pixel quality b..., , # Global overview of cloud-, snow-, and shade-free Landsat (1982-2023) and Sentinel-2 (2015-2023) data

Suggested citation: Lewińska, Katarzyna Ewa, et al. (Forthcoming 2024). Global overview of cloud-, snow-, and shade-free Landsat (1982-2023) and Sentinel-2 (2015-2023) data [Dataset]. Dryad. [https://doi.org/10.5061/dryad.gb5mkkwxm](https://doi.org/10.5061/dryad.gb5mkkwxm)

## Description of the data and file structure

A global overview of usable (i.e., cloud-, snow-, and shade-free) 1982-2023 Landsat and 2015-2023 Sentinel-2 data, derived for a regular 0.18° x 0.18°-point grid.

Dataset featured in Lewińska, K.E., Ernst, S., Frantz D., Leser U., Hostert P., (year), Global overview of usable Landsat and Sentinel-2 data for 1982-2023, Submitted to Data in Brief

The complete dataset comprises three .csv files:

* GLOBAL_LND_1982-2023_CSO.csv: Daily data availability derived from Landsat 1982-2023 archives
* GLOBAL_S2_2015-2023_CSO.csv: Daily data availability derived from Sentinel...