Doppler Orbitography and Radiopositioning Integrated by Satellite (DORIS) Ionospheric Product from the NASA Crustal Dynamics Data Information System (CDDIS). DORIS is a dual-frequency Doppler system consisting of a receiver flying aboard a satellite and a globally distributed network of ground beacons. The DORIS receiver on-board the orbiting satellite tracks the dual-frequency radio signals transmitted by the network of ground beacons and generates the DORIS data. A measurement is made of either the Doppler shift or absolute phase as the satellite’s orbit moves over the ground-based beacon. DORIS data records contain a time-tagged range-rate measurement with associated ancillary information. DORIS observations from a global network can be utilized for a variety of products. Analysis Centers (ACs) of the International DORIS Service (IDS) retrieve DORIS data on a regular basis to compute various DORIS products from data generated by the DORIS beacons supporting the IDS network. These products include ionospheric products providing time derivatives of the Total Electron Content (TEC) obtained from the DORIS doppler data. These DORIS derived ionospheric products are available in text format.

• Data link
• Metadata link
• undefined

CDDIS Short Name: DORIS_IDS_ion_prods Version ID: 1 Unique ID: C1602863162-CDDIS

Station position time series solutions in DORIS Station Coordinate Difference (STCD) format derived from analysis of Doppler Orbitography by Radiopositioning Integrated on Satellite (DORIS) data. These products are the generated by analysis centers in support of the International DORIS Service (IDS).

• Data link
• undefined
• Metadata link

CDDIS Short Name: DORIS_IDS_sta_coord_prod Version ID: 1 Unique ID: C1000000080-CDDIS

Doppler Orbitography by Radiopositioning Integrated on Satellite (DORIS) Weekly Station Position Product from the NASA Crustal Dynamics Data Information System (CDDIS). DORIS is a dual-frequency Doppler system consisting of a receiver flying aboard a satellite and a globally distributed network of ground beacons. The DORIS receiver on-board the orbiting satellite tracks the dual-frequency radio signals transmitted by the network of ground beacons and generates the DORIS data. A measurement is made of either the Doppler shift or absolute phase as the satellite’s orbit moves over the ground-based beacon. DORIS data records contain a time-tagged range-rate measurement with associated ancillary information. DORIS observations from a global network can be utilized for a variety of products. Analysis Centers (ACs) of the International DORIS Service (IDS) retrieve DORIS data on a regular basis to compute weekly station position solutions for the DORIS beacons supporting the IDS network. The IDS Analysis Center Coordinator combines these individual AC solutions in a standard least-squares adjustment to generate the official IDS weekly combined station position solution.

• Data link
• Metadata link
• undefined

CDDIS Short Name: DORIS_IDS_wkly_pos_prod Version ID: 1 Unique ID: C1544924806-CDDIS

Doppler Orbitography by Radiopositioning Integrated on Satellite (DORIS) Data (multi-day files) from the NASA Crustal Dynamics Data Information System (CDDIS). DORIS is a dual-frequency Doppler system consisting of a receiver flying aboard a satellite and a globally distributed network of ground beacons. The DORIS receiver on-board the orbiting satellite tracks the dual-frequency radio signals transmitted by the network of ground beacons and generates the DORIS data. A measurement is made of either the Doppler shift or absolute phase as the satellite’s orbit moves over the ground-based beacon. DORIS data records contain a time-tagged range-rate measurement with associated ancillary information. The data records also contain information about any corrections that may have been applied during the processing phase, such as for the ionosphere, troposphere, and satellite center of mass, among others. Furthermore, meteorological measurements (e.g., temperature, relative humidity, ground pressure) recorded by instruments co-located with the ground-based beacons are included with the DORIS data and can be used to determine the tropospheric correction. DORIS data in the original format are also supplied to the data center in multi-day files, corresponding to the mission’s data processing arc, and are forwarded approximately 20 days after the end of the last observation day contained in the file. More information about these data is available on the CDDIS website at https://www.earthdata.nasa.gov/centers/cddis-daac/data-access-tools

• Data link
• Metadata link
• undefined

CDDIS Short Name: DORIS_multiday_data Version ID: 1 Unique ID: C1538790162-CDDIS

Understanding of changes in the extent of the Heard Island glaciers has been derived from comparison of brief journal accounts, photographs and drawings made during the early sealing period and later, as scientists began to explore this remote island, from published reports, photographs, satellite images and eventually mass-balance studies. The fluctuations of these glaciers have previously been discussed by Budd and Stephenson (1970), Allison and Keage (1986), Budd (2000), Ruddell (2006), Donoghue (2009), and Cogley et al (2014). This report examines two newly acquired satellite images from 2012 and 2014. What is unique about these images is that in both cases the images are near cloud free and include the entire island. This is unusual for this mountainous island. These images provide the first chance to complete a full inventory of the island's glaciers over both years (2012 and 2014) from a single point in time. Complete satellite inventories of the island have only previously been attempted in 1988 and 2008 - in each case this required the use images over several years and different sources to capture the entire island. This report also includes an inventory of additional data sets and data resources that have been used to calculate the length and areas of Heard Island glaciers between 1947 and 2014.

• Metadata link
• Heard_2016_glaciers

AU_AADC Short Name: Heard_2016_glaciers Version ID: 1 Unique ID: C1278276920-AU_AADC