COWVR and TEMPEST on Space Test Program-Houston 8 (STP-H8) COWVR and TEMPEST on Space Test Program-Houston 8 (STP-H8) About Mission Objectives
The Department of Defense (DoD)-sponsored Space Test Program-Houston 8 (STP-H8) mission, carrying Jet Propulsion Laboratory (JPL)'s COWVR (Compact Ocean Wind Vector Radiometer) and TEMPEST (Temporal Experiment for Storms and Tropical Systems) instruments, aims to demonstrate new low-cost microwave sensor technologies for weather applications. Additionally, a Science Working Group (SWG) named Air-Sea interface and Atmospheric Profile observatory (ASAP) was formed in early 2021 to provide community leadership for advancing the research and applications using COWVR and TEMPEST measurements. The simultaneous measurements of air-sea interface and atmospheric profiles present significant advantages for research and applications in storm forecasting, weather and atmospheric dynamics, air-sea interactions, climate sciences, and model improvements. The ASAP-SWG is composed of scientists from NASA (JPL, GSFC, MSFC), DoD, NOAA, universities, private sector, and Météo France. Tony Lee (JPL), Ben Ruston (JCSDA), Clark Rowley (NRL) and Hui Su (JPL) serve as ASAP-SWG co-chairs.
COWVR and TEMPEST were launched on Dec. 21, 2021 at 5:07am EST from the Kennedy Space Center to the International Space Station (ISS) as part of SpaceX’s 24th Commercial Resupply Mission (CRS-24). The instruments were deployed to the JEM-EF module of the ISS to commence a planned 3-year operation. The real-time data stream of COWVR and TEMPEST measurements will be delivered via the Tracking and Data Reply Satellite System (TDRSS) with a latency of minutes. The first public release of data is planned in early 2024, following the calibration/validation period.
Both COWVR and TEMPEST provide brightness temperature measurements at their respective frequencies. The first set of derived physical variables include ocean surface winds and column-integrated water quantities (cloud liquid water, precipitable water vapor). With NASA's support, members of the ASAP-SWG will also develop products for water vapor profile, precipitation rate, and ice water path using the STP-H8 mission measurements. PO.DAAC is NASA’s designated archive and distribution center for the STP-H8 mission data, with the science data provided in HDF-5 format. These measurements will supplement the PO.DAAC archive with data that are non-sun-synchronous, enhancing existing measurements from sun-synchronous sensors/platforms. The anticipated data products for different variables are listed in Table 1.
NASA contributions to the mission: NASA funded the development of TEMPEST-D and its spare copy, which became TEMPEST-H8, through the Earth Ventures Technology Demonstration Program. NASA also provided the launch as a part of the ISS crew resupply missions. A little more loosely tied is that COWVR uses receiver designs from Jason-3, which was an instrument originally developed by JPL for NASA to support the Jason altimeter mission.
Table 1. Anticipated data products from COWVR and TEMPEST
Variable
Spatial Resolution
Expected uncertainty
Data producer
Wind vector (speed and direction)
30 km
Wind speed < 6 m/s
Wind speed between 6 & 12 m/s
Wind speed
> 12 m/s
JPL
38°
16°
8°
1 m/s
1 m/s
1 m/s
Precipitable water vapor
30 km
< 0.3 cm
JPL
Cloud liquid water
30 km
0.05 mm
JPL
Precipitation rate
15 km
TBD
*CSU/JPL
Ice water path
15 km
<50% for IWP>200g/m2
*CSU
Water vapor profile
15 km
15%
*CSU
Brightness temperature
13-30 km
< 0.3K
JPL
*NASA funded development
Instruments
Compact Ocean Wind Vector Radiometer (COWVR) performs conical imaging at three frequencies (18.7, 23.8, and 33.9 GHz) with six (full) polarizations for each frequency, thereby providing a total of eighteen channels.Temporal Experiment for Storms and Tropical Systems (TEMPEST) performs cross-track imaging at five frequencies (89, 166, 176, 180, and 182 GHz).
Table 2. COWVR and TEMPEST key sensor characteristics:
Frequency
Polarization
Brightness temperature uncertainty
Spatial resolution
Swath width
COWVR
18.7, 23.8, 33.9 GHz
Full polarizations for each frequency
(*H,V,P,M,L,R)
<0.3K
18.7 GHz: 30x19 km;
23.8 GHz: 23x15 km;
33.9 GHz: 16x10 km
890 km
TEMPEST
89, 166, 176, 180, 182 GHz
<0.5K
(at nadir)
89 GHz:
25 km;
166-182 GHz: 13 km
1400 km
*H: Horizontal; V: Vertical; P: +45°; M: -45°; L: Left-hand circular; R: Right-hand circular
Related Links
References
Brown, Shannon, Paolo Focardi, Amarit Kitiyakara, Frank Maiwald, Lance Milligan, Oliver Montes, Sharmila Padmanabhan et al. "The COWVR Mission: Demonstrating the capability of a new generation of small satellite weather sensors." In 2017 IEEE Aerospace Conference, pp. 1-7. IEEE, 2017.
Brown, Shannon, Paolo Focardi, Amarit Kitiyakara, Frank Maiwald, Oliver Montes, Sharmila Padmanabhan, Richard Redick, D. Russel, and James Wincentsen. "The compact ocean wind vector radiometer: A new class of low-cost conically scanning satellite microwave radiometer system." In Proc. IEEE Geosci. Remote Sens. Soc.(IGRSS), 35th Can. Remote Sens. Soc.(CSRS), pp. 1-3. 2014.
Farrar, Spencer, Steven Swadley, Shannon Brown, Eric Simon, Sayak Biswas, David Kunkee, and Kieran Smith. "An Initial on-Orbit Performance Assessment of the Compact Ocean Wind Vector Radiometer (COWVR)." In IGARSS 2024-2024 IEEE International Geoscience and Remote Sensing Symposium, pp. 6277-6281. IEEE, 2024.
Documentation
Documents provided here include information on the general COWVR-TEMPEST project. A complete set of documents specific to each data product (if further resources are available) can be found on that product's landing page.
COWVR EDR User Guide , quick-start to learn about the Level 2 wind and water vapor product and work with the files. Additionally provides instrument validation results.COWVR Algorithm Theoretical Basis Document , detailed description of algorithms for processing and calibration of COWVR.COWVR EDR Data Product Development Document , includes an overview of the COWVR-TEMPEST project, the COWVR instrument, and EDR file contents. COWVR TSDR Data Product Development Document , includes an overview of the COWVR-TEMPEST project, the COWVR instrument, and TSDR file contents. TEMPEST TSDR Data Product Development Document , includes an overview of the COWVR-TEMPEST project, the TEMPEST instrument, and TSDR file contents.
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