Center for Research on Envrionment & Water (CREW)

Water and Energy Cycle EOS Clearing HOuse (WECHO)

Project Summary:

Water has long been known to be essential to human activity. Both plants and animals upon which humans depend require water to survive. The ability to monitor and to study the amount and location of water is critical for the management of earths resources. To this end, metadata in NASAs EOS ClearingHouse (ECHO) is an essential information resource for connecting water users to the best available data.

In response to Appendix A.19 Advancing Collaborative Connections for Earth System Science (ACCESS) to enhance and improve existing components of the data and information systems infrastructure supporting NASA's Earth science research communities, a new EOS Clearing House (ECHO) client is being proposed. The purpose of this client is to use ECHO middleware technology to provide access to and discovery of NASA data related to the global Water and Energy Cycle. Science and technology professionals will be able to access NASA data and services via a web-based tool tightly integrated with ECHO Application Program Interfaces (APIs) to combine and then display via the client web browser data sets and subsets within the realm of ECHOs' holdings. The objective is to establish practical applications that benefit the research of the community of known science users and extend those benefits to society at-large.

Interfacing with the ECHO API, the user of this new ACCESS client will be able to browse Water and Energy Cycle related holdings and then display characteristics of the data set(s). This new portal will incorporate statistical and quantitative graphical displays allowing the user to apply educated human insight and analysis in the formulation of new hypothesis and the validation of current theories.

The portal will be based upon industry standards for performing web-based computing.

Introduction

Water is life. It is a central component of the Earth system and is essential for society's welfare, progress and sustainable economic growth. The water cycle operates on a continuum of time and space scales and exchanges large amounts of energy as water undergoes phase changes moving from one part of Earths system to another; it is a major driving agent of global circulation.

These are three primary motivations to quantify the water and energy cycle:

Water vapor is by far the largest and most variable contributor to the global greenhouse effect.
Latent heat fluxes associated with water vapor transport, precipitation and evaporation are the principal mode of energy exchange between Earth and atmosphere; it is the main driver of weather.
Constant renewal of fresh water reserves is a crucial conditon for the existence of life on Earth; global evaporation, atmospheric transport and precipitation are the processes that control the renewal of fresh water resources.

Project Description

Goals & Objectives:The primary goal if this project is to develop a new Water and Energy Cycle (WEC) EOS Clearing HOuse (ECHO) client, WECHO, that will use ECHO middleware technology to provide acess to and discovery of data resources related the the NASA Global Water and Energy Cycle Focus Area.

Following this goal, these objectives will be addressed:

provide a web portal customized to the needs of NASA's Water and Energy Cycle Focus Area user community;
maximize NASA observational investments by facilitating the integration of water and energy cycle research results;
optimize the use of the new generation of research satellites and revolutions in modelling capability;
provide physical linkages to NASA satellite data products by putting them in a physically-based water and energy cycle balance context;
allow users to integrate disparate information sources to analyze the water and energy cycle;
promote an improved understanding of the global cycling of the water and energy;
allow for the evaluation of modeling skill and deficiencies in predicting polar water and energy cycling;
facilitate portal usability by not only the science community, but also with water and energy stakeholders, educatirs and the general public.

ECHO Overview:The EOS Clearing HOuse (ECHO) stores metadata descriptors for more than 2,129 data collections comprising 54 million individual data granules and 13 million browse images. Most of this spatial and temporal metadata is from Distributed Active Archive Centers (DAACs) sources. ECHO's application program interfaces (APIs), based upon industry standards for web-based computing, empower the science community to directly access NASA data and information.

Tools:The vision is for WECHO to enable the user to perform limited data browsing and visualization through the WECHO portal. Both data management and the infrastructure of ECHO will use the in-house Grid Analysis and Display System (GrADS) and a GrADS Data Server (GDS). GrADS is an interactive desktop tool that is used for integrated access, analysis and display of Earth science data (gridded or in situ). The format of the data may be HDF, netCDF, GRIB or binary. It may be accessed over the internet via the OPeNDAP protocol using GrADS. GrADS is open source, has extensive online documentation, and is distributed for all common desktop operating systems. The GDS is an OPeNDAP server that integrates the data access and analysis capabilities of GrADS with the OPeNDAP protocol. The GDS provides remote data access subsetting for all the data formats and data types that GrADS supports (including GRIB, BUFR, and in-site station observations). The GDS provides a powerful remote analysis capability using an on-demand approach where specificed parameters of an analysis operation combined with a specified space-time domain are used to dynamically create and serve the desired set. OPeNDAP provides freely available software that makes local data accessible to remote locations regardless of local storage format. The Data Access Protocol (the DAP part of OPeNDAP) consists of a model, a common network representation for both metadata and data and a flexible subsetting mechanism. This method insulates the end users from the particularities of the datas local storage format.

flowchart image of WECHO communication between client and server

Project Benefits:

It is hoped that via some extensions to the WECHO portal, for example a web page interface for users seeking to interactively display data, that a user may sit in front of a networked terminal and, by providing a specific Universal Resource Location (URL) to an image-capable browser, display images of Water and Energy Cycle data relevant to the users area of interest. This should empower researchers, scientists, students and others with interest in the Earths Water and Energy Cycle to use the most dynamic and valuable resource on the planet---human cognative power---to better understand this portion of Earths complex system.

This project is being done in cooperation with the George Mason University College of Science.

Last Updated: 9 January 2008