Potential Landsat Contributions for GEO-C Initiative Zhiliang Zhu, USGS 24 October, 2017

The need for land and water data in global carbon observation Land sector (both emissions and sinks) represents 20% of the total global budget Uncertainty is highest for land sink Better land data is needed, Landsat is the best choice, as it has been used broadly USGS is working on making it even more useful/operational for EO Global Carbon Project, Quéré et al 2016

History of Landsat The longest and most comprehensive record of the Earth’s land and water surface

What makes Landsat useful to Carbon Observation? Landsat Data Usages (10/01/2015 through 09/30/2016) Free, open, and easy access Global acquisition Calibrated, science-quality data Resolution sufficient to distinguish between natural and human-induced land change Continuous 45+ year archive

Potential Landsat contributions to carbon observation and GEO-C tasks Land base representation for GHG inventories Attribution for land use change Specific fluxes e.g. wetlands, aquatic (rivers, lakes, reservoirs), and disturbance such as wildfire GEO-C Tasks User needs and policy interface Data access and availability Optimization of observational networks Budget calculations and breakdowns

Current US approach for land base representation EPA National GHG Inventory Report Forest and agriculture inventories Landsat-based mapping by USGS

Landsat is found to be the most suitable RS tool for land base representation No discernable trend in accuracy with time or study area There is general pattern between sensor types Yu et al 2014, Meta-discoveries from a synthesis of satellite-based land-cover mapping research, IJRS

Emergence of Landsat models to track land use changes Vegetation change tracker (VCT), Huang et al 2010 LandTrender, Kennedy et al 2010 Continuous change detection and classification (CCDC), Zhu and Woodcock 2014 Examples of the recent models: Common concept of the models:

Emergence of Landsat models to track land use changes Current results from the use of CCDC model, showing land change over the last 30 years in the U.S. Puget Sound region

How well do the models improve land use change tracking How well do the models improve land use change tracking? – More data points = more accurate land base representation (C. Huang, unpublished data on tree-height modeling with Landsat)

Landsat Essential Climate Variables - Wildfire Area Emission

Landsat Essential Variables – Dynamic Surface Water Extent

USGS efforts to make Landsat more operational for EO: Analysis Ready Data Landsat data processed to a level that enables direct use in applications Allows geospatial, multi-spectral, and multi-temporal manipulations for the purposes of data reduction, analysis, and interpretation Consistent radiometric processing scaled to TOA and surface reflectance Consistent geometry including spatial coverage and cartographic projection – e.g., pixels align through time Metadata of sufficient detail on data provenance, geographic extent, and data quality

Building on the ARD: USGS Land Change Mapping, Analysis, Projection (LCMAP) Program LCMAP is an institutional asset capable of producing national and global land use change maps at 30 meter resolution Also is capable of on-demand data products The program is scheduled to go operational in 2018 and we expect it will be a major contribution to tools needed for carbon observation

Prototyping LCMAP change products for ecosystem carbon tracking 1986 1995 2010

Summary Landsat is uniquely suited to carbon observations: spatial resolution, temporal coverage, spectral characteristics, and USGS commitment to data quality Landsat contributes to global carbon observations in several key areas: land base representation, land use attribution, and specific land fluxes Improvements in Landsat data processing standard and modeling are poised to advance good practice guidance and other applications for carbon observation As the result, supporting global carbon monitoring will further enhance the value of Landsat Thank you!