Introduction
The NASA Carbon Monitoring System effort seeks to improve monitoring of carbon stocks and fluxes through the application of satellite remote sensing resources along with observational and modeling capabilities. Program goals include the development of capabilities for improved characterization, quantification, understanding, and prediction of the evolution of global carbon sources and sinks on regional, national and global scales. The need for improved carbon monitoring capabilities is in recognition of the contribution by greenhouse gas emissions to climate change.
Changing climate, coupled with the impacts of human activity, has the potential to dramatically alter coupled hydrologic-biogeochemical processes and associated movement of water, carbon and nutrients through various terrestrial reservoirs. Such changes will result in dramatic changes in terrestrial environments, biogeochemistry, and delivery of dissolved and particulate materials from terrestrial systems into rivers, estuaries, and coastal ocean waters [Tian et al., 2014].
Effective management requires an integrated process model-based approach with predictive skill that is able to account for such impacts under different carbon management scenarios. To date, there have been limited efforts to attempt to integrate climate- and human-related impacts across terrestrial environments to coastal and ocean margin ecosystems. A challenge for decision makers has been the ability to access the vast amount of scientific information in a form that is useful in making policy decisions [Dilling, 2007; Dilling and Lemos, 2011; McNie, 2007]. Therefore, it is essential that information be provided in an accessible and usable manner. Ideally, iteration between information provider and user can improve impacts of the information.
As part of previous NASA projects, our team developed an integrated suite of terrestrial and coastal ocean ecosystem models that were used to examine processes controlling fluxes on land, their coupling to riverine systems, the delivery of materials to estuaries and the coastal ocean, and the associated marine ecosystem responses. The coupled terrestrial-ocean ecosystem model suite focused on the Mississippi-Atchafalaya River basin (MARB) and the northern Gulf of Mexico (GOM).
In this project, we are conducting model evaluation, improvement, and documentation, and are extending the domain of our integrated framework of terrestrial and ocean models beyond the MARB and GOM to include regions of the southern and southeastern U.S. and the South Atlantic Bight (SAB). This includes examining carbon storage in soils and vegetation, land-atmosphere exchanges of carbon (including methane), export of materials to the coastal ocean and consequences for associated carbon fluxes in the coastal environment, and projecting future changes under different scenarios of climate and human impact.
The unique nature of our approach, coupling models of terrestrial and ocean ecosystem dynamics and associated carbon processes, will allow for assessment of how societal and human-related LCLUCF, as well as climate change, affects terrestrial carbon sources and sinks, export of materials to coastal margins, and associated carbon processes in the continental margins. Methods, models and scenarios such as these have the potential to inform the decision processes related to carbon management and may assist in setting realistic goals for states and the Nation [Galik and Jackson, 2009; Law and Harmon, 2011; Melillo et al., 2014]. Moreover, our approach provides an improved understanding of how changes from anthropogenic pressures, associated land use activities, and climate will alter export of terrestrial materials that may affect coastal ecosystem integrity. In the MARB/GOM region, a striking example of water quality impacts is evident as annual seasonal hypoxia creates obstacles to achieving healthy, diverse and sustainable fisheries, particularly as an uninhabitable environment is created for benthic marine fauna impacting the entire food web as well as Gulf economy [EPA, 2013]. Further impacts to the Gulf region, in water quality, habitat, and biological resources have occurred as a result of the Deepwater Horizon oil spill, and impacts will likely persist into the future [NRDA, 2012]. Exploring watershed-based modeling scenarios coupled with remotely sensed and ship-board survey data will inform effective water quality, hydrology, and restoration policy based on the magnitude, temporal and spatial patterns of loading and response.
Project Summary
The NASA Carbon Monitoring System effort seeks to apply satellite remote sensing resources along with observational and modeling capabilities to improve monitoring of carbon stocks and fluxes, particularly as they contribute to the development of Monitoring, Reporting and Verification (MRV) system capabilities. Our prior NASA-funded research employs a combination of models and remotely-sensed and in situ observations to develop georeferenced products and associated uncertainties for land-ocean exchange of carbon, air-sea exchanges of carbon dioxide, and coastal to open ocean exchanges of carbon. A major aspect of this project has been to establish and populate geospatial portals for sharing and analysis of carbon datasets and products. The primary region of study has been the Mississippi River watershed and northern Gulf of Mexico. The unique nature of our approach, coupling models of terrestrial and ocean ecosystem dynamics and associated carbon processes, allows for assessment of how societal and human-related land cover and land use change and forestry (LCLUCF) and climate-related change affect terrestrial carbon storage and fluxes, as well as export of materials through watersheds to the coastal margins.
Here, we extend the domain of our observational and integrated terrestrial-ocean ecosystem model system to include the southeastern U.S. and South Atlantic Bight. In addition to land-ocean and sea-atmosphere exchanges, we utilize satellite observations together with the capabilities of the terrestrial ecosystem model to characterize and quantify terrestrial carbon storage and fluxes, including land-atmosphere fluxes of both carbon dioxide and methane. Our approach includes assembling model products along with associated uncertainties and errors in a geospatial framework that will facilitate decision support for carbon and land use management.
This project aids the effective implementation of MRV approaches, which require an understanding of the contributions of individual forest and other ecotypes beyond local to regional- and national-scale carbon processes. Furthermore, our efforts will aid in governance and decision support related to carbon management, including the ability to evaluate different LCLUCF scenarios in the context of changing climate conditions. Extended impacts of forest and other land use management strategies on carbon storage and transport, including in soils and into watersheds and coastal margins will be assessed. Finally, this information will be readily accessible as a geo-referenced product to support operational needs of stakeholders.
Objectives
Expand the spatial domain of our observational and integrated modeling approach to include the Mississippi River basin and southeastern U.S., and examine terrestrial carbon storage and fluxes including characterization and quantification of soil and vegetative carbon biomass and land-atmosphere, land-ocean, and sea-atmosphere fluxes of carbon dioxide and methane.
Examine different LCLUCF scenarios within the terrestrial domain and different climate scenarios to assess effectiveness of carbon management strategies.
Engage with other CMS projects and stakeholders (e.g., USDA, National Climate Assessment) to identify user needs related to carbon management and MRV activities, modify and expand the scope of information based on user feedback.
Continue to develop the Google Earth web portal with carbon products and explore possible transition of prototype products to fully operational status.