Giovanni is a NASA Goddard Earth Science Data and Information Services Center (GES DISC) Distributed Active Archive Center (DISC) web application that provides a simple, intuitive way to visualize, analyze, and access Earth science remote sensing data, particularly from satellites, without having to download the data.
NASA’s Global Change Master Directory (GCMD) metadata and keyword structures are one of NASA’s contributions to the international Committee on Earth Observation Satellites (CEOS), where the GCMD is known as the CEOS International Directory Network (IDN). The GCMD was deprecated by NASA’s Earth Science Data and Information System (ESDIS) Project in June 2020. While no changes were made to the directory, all legacy GCMD links now redirect to the CEOS IDN.
The Global Land Ice Measurements from Space (GLIMS) initiative is an international project to inventory the world's estimated 200,000 glaciers and to create a comprehensive, global database of land ice through repeat surveys.
GLIMS uses data collected by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument aboard the Terra satellite and the NASA/USGS Landsat series of satellites, but other sources are also used. These additional sources include other satellite observations, such as observations from Satellite Pour l’Observation de la Terre (SPOT) and EMI+, as well as maps, aerial photographs, and historical observations dating back to 1850.
This data collection's primary data product is the GLIMS Glacier Database. The glacier database includes measurements of glacier geometry, glacier area, snowlines, supraglacial lakes and rock debris, and other glacial attributes, as well as browse images. The collection includes data from approximately 70 percent of the world's 200,000 glaciers, and new glaciers are continually added.
Each polygon within the Glacier Outlines layer represents the extent of a particular glacier at a specific time, as well as other possible features of the glacier such as the extent of debris cover or the location of supra-glacial and pro-glacial lakes.
The Global Positioning System (GPS) is the U.S. version of a Global Navigation Satellite System (GNSS). A GNSS system like GPS has three components: satellites in well-known orbits with synchronized clocks, ground controllers, and a ground segment providing data to users. Using signals from four satellites, a precise location in three-dimensions (within millimeters or less) along with precise time can be determined. By comparing measurements over time, minute elevation and distance changes at a station can be calculated.
Harmonized Landsat Sentinel-2 (HLS) imagery is produced from data acquired by the Operational Land Imager (OLI) and OLI-2 instruments aboard the joint NASA/USGS Landsat 8 and Landsat 9 satellites and the Multi-Spectral Instrument (MSI) aboard the ESA (European Space Agency) Sentinel-2A and Sentinel-2B satellites.
HLS data is available from Earthdata Search.
The Hierarchical Data Format (HDF) is a data model, file format and I/O library designed for storing, exchanging, managing and archiving complex data including scientific, engineering, and remote sensing data. The latest version of HDF, HDF5 allows users to read only the data that they need, not the whole file. Data producers can put images, tables, multidimensional arrays, etc into the same file.
The High-level Tool for Interactive Data Extraction (HiTIDE) allows users to subset and download popular Level 2 datasets at NASA’s Physical Oceanography Distributed Active Archive Center (PO.DAAC). Users can search across a wide variety of parameters, such as variables, sensors and platforms, and filter the resulting data based on spatial and temporal boundaries of interest to the user.
The Integrated Multi-satellitE Retrievals for GPM (IMERG) algorithm combines information from the GPM satellite constellation to estimate precipitation over the majority of Earth's surface.
NASA's Earth Science Division (ESD) International Organization for Standardization (ISO) 19115 Geographic Metadata Standard - Implementation Requirement and Guidance document describes the ESD-approved implementation guidelines for required metadata to be included in science data products.
Lidar stands for Light Detection and Ranging. It is a remote sensing method that uses light in the form of a pulsed laser to measure ranges. Lidar is the optical analogue of radar. Lidar differs from radar in its energy source, a laser in the optical part of the electromagnetic spectrum (near IR and green).
Lidar is used to measure things such as:
- range and altitude
- atmospheric vertical profiles of aerosols and trace gas densities
- cloud cover
- wind velocity
- shape and size of landscape features
- height and density of forests
- sea surface roughness
Machine learning automates analytical model building. It uses methods from neural networks, statistics, operations research and physics to find hidden insights in data without being explicitly programmed where to look or what to conclude. For more information see Artificial Intelligence and the articles below.
NASA's Oak Ridge National Laboratory Distributed Active Archive Center (ORNL DAAC) MODIS and VIIRS Subsetting Tools Suite provides several means of subsetting Moderate Resolution Imaging Spectroradiometer (MODIS) and Visible Infrared Imaging Radiometer Suite (VIIRS) data.
Natural language processing is the ability of computers to analyze, understand and generate human language, including speech. The next stage of NLP is natural language interaction, which allows humans to communicate with computers using normal, everyday language to perform tasks.
Remote sensing of nighttime light emissions offers a unique perspective for investigations into human behaviors. The Visible Infrared Imaging Radiometer Suite (VIIRS) instruments aboard the joint NASA/NOAA Suomi National Polar-orbiting Partnership (Suomi NPP) and NOAA-20 satellites provide global daily measurements of nocturnal visible and near-infrared (NIR) light that are suitable for Earth system science and applications studies. Learn more in the Nighttime Lights Backgrounder.
Enables scientists to share data more easily over the internet. The OPeNDAP group is also the original developer of the Data Access Protocol (DAP) that the software uses. Many other groups have adopted DAP and provide compatible clients, servers, and SDKs. OPeNDAP’s DAP is also a NASA community standard.
OpenAltimetry is a cyberinfrastructure platform for discovery, access, and visualization of data from NASA’s ICESat and ICESat-2 missions. It is the product of a collaboration between the National Snow and Ice Data Center (NSIDC), UNAVCO, the Scripps Institution of Oceanography, and the San Diego Supercomputer Center at UC San Diego.
Panoply, developed by NASA's Goddard Institute for Space Studies (GISS), is a cross-platform application that plots geo-referenced and other arrays, from Network Common Data Form (NetCDF), Hierarchical Data Format (HDF), and GRIdded Binary (GRIB). Panoply offers additional functionality, such as slicing and plotting arrays, combining arrays, and exporting plots and animations.