Meteorological Satellites (MetSat) Overview of the global network of Meteorological Satellites. Speaker: Markus Dreis (EUMETSAT)

Transcription

1 Meterlgical Satellites (MetSat) Overview f the glbal netwrk f Meterlgical Satellites Speaker: Markus Dreis (EUMETSAT) Secnd ITU/WMO Seminar "Use f Radi Spectrum fr Meterlgy: Weather, Water and Climate Mnitring and Predictin", Geneva, 23 t 24 Octber

2 Rle f MetSat in the WMO Glbal Observing System (GOS) The space-based cmpnent f GOS fr the measurement f envirnmental and meterlgical data includes tw cnstellatins: gestatinary (GSO) and nn-gestatinary () lw Earth-rbiting, mstly plar-rbiting bservatin satellites. and GSO MetSat satellites are nrmally equipped with visible and infrared imagers and sunders, frm which ne can derive many meterlgical parameters. The plar-rbiting satellites are als equipped with active and passive micrwave sensing instruments that prvide fr example vertical prfiles f temperature and humidity n a wrldwide basis. The huge amunt f parameters and data frm sensrs n MetSat satellites resulted in significant imprvements in Numerical Weather Predictin (NWP). In additin t the instruments n bard, MetSat satellites als carry data cllectin systems (DCS) which gather basic meterlgical and envirnmental data fr the GOS frm data cllectin platfrms (DCPs) lcated anywhere in the wrld (mstly at remte lcatins r buys at sea (e.g. fr Tsunami warning)). 2

3 Overview f Instrument Types and Missins n MetSat systems GSO MetSat: Visible imagers Infrared imagers Infrared sunders (future) Data Cllectin System Search and Rescue Further instruments (individual t different MetSat systems) MetSat: Visible imagers Infrared imagers Infrared sunders Data Cllectin System Search and Rescue Active micrwave sensrs Passive micrwave sensrs Further instruments (individual t different MetSat systems) 3

4 Current glbal netwrk f MetSat in the WMO GOS The actual list f currently peratinal MetSat and their parameters is available at: 4

5 Cnstellatin f planned MetSat fr the WMO GOS Operatinal cntinuity in the space-based meterlgical bservatins is ensured by replacing existing series f meterlgical satellites with new r next generatin meterlgical satellites. Next generatin MetSats have significantly increased bservatin capabilities and instrument reslutin, resulting in crrespnding higher data vlume available t the meterlgical user cmmunity. 5

6 Definitin f MetSat in the ITU Radi Regulatins MetSat is defined in N f the Radi Regulatins (RR) as an Earth explratin-satellite service fr meterlgical purpses. It allws the radicmmunicatin peratin between earth statins and ne r mre space statins, which may include links between space statins, with links t prvide: Infrmatin relating t the characteristics f the Earth and its natural phenmena, including data relating t the state f the envirnment, btained frm active r passive sensrs n Earth satellites; Infrmatin cllected frm airbrne r Earth-based platfrms; Infrmatin distributed t earth statins; Feeder links necessary fr the peratin f MetSat satellites and its applicatins. 6

7 MetSat radi-frequency transmissins Radi-frequencies are used fr the fllwing MetSat applicatins (nt including active and passive micrwave sensing): telemetry, telecmmand and ranging f the spacecraft transmissins f bservatin data frm MetSat satellites t main receptin statins; re-transmissins f pre-prcessed data t meterlgical user statins thrugh MetSat satellites; direct bradcast transmissins t meterlgical user statins frm MetSat satellites; alternative data disseminatin t users (GEONETCast) via ther satellite systems than MetSat (nt in MetSat/EESS allcated frequency bands); transmissins frm Data Cllectin Platfrms thrugh MetSat satellites; relay f Search and Rescue messages (COSPAS-SARSAT). 7

8 8 General Cncept f MetSat Systems

9 Data Transmissin Cncepts f MetSat Systems The raw data gathered by the instruments n-bard gestatinary MetSats are permanently transmitted t a primary grund statin f the perating agency, prcessed, and distributed t varius natinal meterlgical centres, t fficial archives, and ther users. Prcessed data frm gestatinary MetSats are either sent back t the meterlgical satellite fr re-transmissin as part f a direct bradcast t user statins via lw and/r high rate digital signals. Different t gestatinary MetSat satellites, where the satellite is permanently in visibility f its grund statins, the raw data acquired by instruments n nngestatinary MetSats have t be gathered and stred n-bard the satellite until they can be transmitted t a primary grund statin f the perating agency when the satellite passes ver such a grund statin. The raw instrument data are then prcessed by the perating agency and prvided t the users by different data disseminatin mechanisms. T imprve the latency f the data, a subset f the data acquired by the instruments are bradcasted directly frm the satellite and can be received by user statins when the satellite is in the visibility f such a user statin which can be lcated anywhere. Such a service is called direct read-ut. In additin, the prcessed data are als distributed t users by using alternative means f data disseminatin, e.g. GEONETCast. 9

10 Frequency band allcatins t MetSat & EESS in the RR Available allcatins fr MetSat data transmissins space-t-earth directin Earth-t-space directin MHz (MetSat primary) MHz (MetSat primary) MHz (EESS and MetSat secndary) MHz (MetSat primary) MHz (EESS primary) (Nte 1) (and space-t-space directin) MHz (EESS and MetSat primary) MHz (EESS primary) (Nte 1) (and space-t-space directin) MHz (MetSat primary, limited t gestatinary satellites nly) MHz (EESS primary) (Nte 1) MHz (MetSat primary, limited t nngestatinary satellites (and space-t-space directin) nly) MHz (EESS primary) (Nte 1) MHz (MetSat primary) GHz ( MetSat primary fr space-t-earth directin in Regin 2, limited t gestatinary satellites nly) GHz (MetSat primary fr space-t-earth directin in Regins 1 and 3, limited t gestatinary satellites nly) GHz (EESS primary) (Nte 1) (and space-t-space directin in GHz) GHz (EESS secndary) (Nte 1) GHz (EESS secndary) (Nte 1) GHz (EESS primary) (Nte 1) GHz (EESS primary) (Nte 1) (Nte 1) Since MetSat is a sub-class f EESS, thse allcatins (fr example: MHz and MHz) can als be used fr the peratin f MetSat satellites and their applicatins. 10

11 Overview f bands and their applicatins mst cmmnly used by current & future MetSat systems Applicatin Orbit Timeline Frequency Band(s) Telemetry/Telecmmand & Ranging MHz MHz future MHz Instrument raw data dwnlink GSO MHz MHz GSO MHz MHz MHz GHz Prcessed data re-transmissin uplink GSO current MHz Lw rate direct disseminatin current MHz t user statins MHz High rate direct disseminatin MHz t user statins MHz GHz Data Cllectin Systems MHz MHz, MHz Search and Rescue MHz MHz 11