Global Precipitation Measurement

Global Precipitation Measurement (GPM) is a joint mission between JAXA and NASA as well as other international space agencies to make frequent (every 2–3 hours) observations of Earth's precipitation. It is part of NASA's Earth Systematic Missions program and works with a satellite constellation to provide full global coverage. The project provides global precipitation maps to assist researchers in improving the forecasting of extreme events, studying global climate, and adding to current capabilities for using such satellite data to benefit society.[1] GPM builds on the notable successes of the Tropical Rainfall Measuring Mission (TRMM), which was also a joint NASA-JAXA activity.

Global Precipitation Measurement
Artist's concept of the GPM Core Observatory
Mission typeEnvironmental research
OperatorJAXA / NASA
COSPAR ID2014-009C Edit this at Wikidata
SATCAT no.39574
Mission durationPlanned: 3 years
Elapsed: 10 years, 8 months, 16 days
Spacecraft properties
ManufacturerNASA GSFC / Ball Aerospace / JAXA / NICT / NEC Toshiba Space Systems
Launch mass3,850 kilograms (8,490 lb)
Power1.95 kW
Start of mission
Launch dateFebruary 27, 2014, 18:37 (2014-02-27UTC18:37) UTC
RocketH-IIA 202 F-23
Launch siteTanegashima Yoshinobu 1
ContractorMitsubishi
Orbital parameters
Reference systemGeocentric
RegimeLow Earth
Semi-major axis6,779 kilometres (4,212 mi)
Perigee altitude400.9 kilometres (249.1 mi)
Apogee altitude415.3 kilometres (258.1 mi)
Inclination65°
Period92.60 minutes
Epoch26 March 2017

The project is managed by NASA's Goddard Space Flight Center, and consists of a GPM Core Observatory satellite assisted by a constellation of spacecraft from other agencies and missions.[2] The Core Observatory satellite measures the two and three dimensional structure of Earth's precipitation patterns and provides a new calibration standard for the rest of the satellite constellation. The GPM Core Observatory was assembled and tested at Goddard Space Flight Center, and launched from Tanegashima Space Center, Japan, on a Mitsubishi Heavy Industries H-IIA rocket. The launch occurred on February 28, 2014, at 3:37 am JST on the first attempt.[3] Agencies in the United States, Japan, India and France (together with Eumetsat) operate the remaining satellites in the constellation for agency-specific goals, but also cooperatively provide data for GPM.[2]

Science objectives

edit

GPM has five broad science objectives:[4]

  • advance precipitation measurement from space
  • improve knowledge of precipitation systems, water-cycle variability and freshwater availability
  • improve climate modeling and prediction
  • improve weather forecasting and climate reanalysis
  • improve hydrological modeling and prediction

Main instruments

edit
Visualization of GPM collecting data on March 17th, 2014 over the last major snow storm of winter 2013–2014 to hit the U.S. east coast.
 
The GPM Core Observatory in the electromagnetic testing chamber at NASA Goddard Space Flight Center in March 2013. The silver disc and drum (center) is the GPM Microwave Imager, and the large block on the base is the Dual-frequency Precipitation Radar.

Dual-Frequency Precipitation Radar (DPR)

edit

The DPR is a spaceborne radar, providing three-dimensional maps of storm structure across its swath, including the intensity of rainfall and snowfall at the surface. The DPR has two frequencies, allowing researchers to estimate the sizes of precipitation particles and detect a wider range of precipitation rates. The Ku-band radar, similar to the PR on TRMM, covers a 245 km (152 mile) swath. Nested inside that, the Ka-band radar covers a 120 km (74.5 mile) swath.[5] Data from the DPR is sent to the ground via a single-access link with TDRSS relay satellites.[6]

GPM Microwave Imager (GMI)

edit

The GMI is a passive sensor that observes the microwave energy emitted by the Earth and atmosphere at 13 different frequency/polarization channels. These data allow quantitative maps of precipitation across a swath that is 885 km (550 miles) wide. This instrument continues the legacy of TRMM microwave observations, while adding four additional channels, better resolution, and more reliable calibration.[5] Data from the GMI is continuously sent to the ground via a multiple-access link with TDRSS relay satellites.[6]

Precipitation data sets

edit

GPM produces and distributes a wide variety of precipitation data products. Processing takes place at the Precipitation Processing System (PPS) at NASA Goddard Space Flight Center, as well as at the JAXA facility in Japan. Data is provided at multiple "levels" of processing, from raw satellite measurements to best-estimate global precipitation maps using combinations of all the constellation observations and other meteorological data. All data from the mission is made freely available to the public on NASA websites.[7] Precipitation data is made available in a variety of formats, spatial and temporal resolutions, and processing levels which are accessible on the Precipitation Measurement Missions "Data Access" webpage.[8] Several data visualization and analysis tools have been made available to provide easy access for the science and applications communities, which include the in-browser Earth science data analysis tool Giovanni,[9] a web API,[10] and a 3D near-realtime global precipitation viewer.[11]

 
Full-Scale Harness Mockup Model of the Core GPM Spacecraft being used for harness assembly inside the Acoustic Chamber at GSFC.

Social media and outreach

edit
This animation shows GPM collecting some of its first data on March 10th over a Pacific storm east of Japan.

In addition to maintaining social media accounts[12][13][14] and the GPM Road to Launch Blog, JAXA and NASA developed several outreach activities specific to this mission prior to launch that the public could participate in. After launch a series of featured articles[15] and videos[16] were produced to highlight various scientific goals and discoveries of the mission, and an "Extreme Weather" blog is maintained to provide timely updates about the latest extreme precipitation events and natural disasters occurring around the world. A Precipitation Education website[17] is also maintained to provide teachers and students with lesson plans, animations, and other resources to teach about the water cycle, Earth science, and the GPM mission.

edit

The main character Mohan Bharghav (Shahrukh Khan) in 2004 Indian film Swades: We, the People is a Project Manager in NASA's GPM project. The movie starts with a press conference pertaining to NASA's GPM, and its upcoming launch. Bharghav discuss the importance of GPM and its positive impact on Earth.[31] In the movie the GPM satellite is launched by the Space Shuttle.[32]

A short anime film of 6 minutes, Dual frequency Precipitation Radar Special Movie, was produced by JAXA and White Fox in 2013.[33]

References

edit
  1. ^ "The Global Precipitation Measurement Mission". NASA. Archived from the original on 2014-02-25. Retrieved 2014-02-19.
  2. ^ a b "Constellation Partners". NASA. Retrieved 2014-02-19.
  3. ^ "GPM Launch Information". NASA. 22 January 2014. Retrieved 2014-02-19.
  4. ^ "Science Objectives." NASA Goddard Space Flight Center. Retrieved: 8 March 2018.
  5. ^ a b "GPM Spacecraft and Instruments". NASA. Retrieved 2014-02-19.
  6. ^ a b "Global Precipitation Measurement Mission Core Observatory". NASA Goddard Space Flight Center. Retrieved: 6 March 2018.
  7. ^ "Explanation of Data Products". NASA. Retrieved 2014-02-19.
  8. ^ "Data Access | Precipitation Measurement Missions". pmm.nasa.gov. Retrieved 2017-01-10.
  9. ^ "Giovanni". giovanni.gsfc.nasa.gov. Retrieved 2017-01-10.
  10. ^ "Precipitation and Applications Viewer | Precipitation Measurement Missions". pmm.nasa.gov. Retrieved 2017-01-10.
  11. ^ "Global Precipitation Viewer | Precipitation Measurement Missions". pmm.nasa.gov. Retrieved 2017-01-10.
  12. ^ "GPM & TRMM Missions (NASA_Rain) on Twitter". Twitter.com. Retrieved 2014-02-26.
  13. ^ "Precipitation Measurement Missions". Facebook. 2014-02-22. Retrieved 2014-02-26.
  14. ^ "NASA Goddard". YouTube. Retrieved 2014-02-26.
  15. ^ "Featured Articles Archive | Precipitation Measurement Missions". pmm.nasa.gov. Archived from the original on 2011-10-16. Retrieved 2017-01-10.
  16. ^ "Gallery: Global Precipitation Measurement". svs.gsfc.nasa.gov. Retrieved 2017-01-10.
  17. ^ "Precipitation Education". pmm.nasa.gov. Retrieved 2017-01-10.
  18. ^ "A Blooming Partnership: Behind the Scenes of JAXA & NASA Missions | NASA". Nasa.gov. 2013-04-12. Archived from the original on 2017-05-22. Retrieved 2014-02-26.
  19. ^ "@NASASocial/JAXA/NASA Cherry Blossoms on Twitter". Twitter.com. 2013-04-12. Retrieved 2014-02-26.
  20. ^ "NASA, JAXA Host 'NASA Social' – a set on Flickr". Flickr.com. 12 April 2013. Retrieved 2014-02-26.
  21. ^ "Cherry Blossoms and Partnerships in Space discussed at NASA Social". YouTube. 2013-04-12. Archived from the original on 2021-12-21. Retrieved 2014-02-26.
  22. ^ "Social Media Accreditation Opens for GPM Media Day | NASA". Nasa.gov. 2013-09-11. Retrieved 2014-02-26.
  23. ^ "GPM NASA Social at Goddard – a set on Flickr". Flickr.com. 15 November 2013. Retrieved 2014-02-26.
  24. ^ "@NASASocial/GPM Media Day on Twitter". Twitter.com. Retrieved 2014-02-26.
  25. ^ "Extreme Weather Photo Contest Winners | Precipitation Measurement Missions". Pmm.nasa.gov. Retrieved 2014-02-26.
  26. ^ "GPM "Let it Snow" Photo Contest Winners | Precipitation Measurement Missions". Pmm.nasa.gov. Retrieved 2014-02-26.
  27. ^ "GPM "Unique Perspectives" Contest | Precipitation Measurement Missions". Pmm.nasa.gov. Archived from the original on 2013-10-23. Retrieved 2014-02-26.
  28. ^ "GPM "Unique Perspectives" Winners". NASA. Retrieved 13 February 2014.
  29. ^ GPM Anime Challenge. "| Precipitation Education". Pmm.nasa.gov. Retrieved 2014-02-26.
  30. ^ "Winners of the GPM Anime Challenge | Precipitation Education". Pmm.nasa.gov. Retrieved 2014-02-26.
  31. ^ 10 Best Bollywood Movies of the Decade Rediff.com retrieved March 01 2014
  32. ^ Gowarikar shoots Swades at Nasa 8 June 2004, Times of India
  33. ^ DPR Dual-frequency Precipitation Radar Special Movie / DPRスペシャルムービー, Sky-Animes
edit