Virtual Supersite Concept

1
Virtual SupersiteConcept

• Martin Hagen
• Institut für Physik der Atmosphäre
• DLR Oberpfaffenhofen
• Germany

2
GPM Ground Validation

• Goal of ground validation (very, very short
  summary)
• validation of GPM precipitation estimates
• provide 3-D atmospheric background for retrieval
  algorithm development,validation and refinement
  
• improve the understanding of microphysics and
  dynamics of precipitation,
• provide error structure of precipitationand the
  underlying physical quantities.

3
GPM Validation Strategy

• Basic Rainfall Validation
• Rain gauge networks
• Radar networks (2-D data), national or
  international
• Supersites (Routine Product Site, RPS)
• Research radar sites, polarimetric radars
  preferred
• soundings, profilers, cloud radars, microwave
  radiometers ...
• Field Campaigns (Focused Observational Program,
  FPO)
• Research radar sites
• Aircraft
• Related to other projects

4
GPM Validation Strategy
5
Europe

• Different Precipitation Regimes
• Various National Weather Services
• National Radar Networks
• Numerous Research Organizations
• Several Sites are candidates for Ground Validation

6
Precipitation in Europe
Sodankylä

• Each site can represent a sub-sample of the
  precipitation systems
• High Latitude Snow
• Mid-Latitude Continental
• Frontal systems
• Stratiform
• Convective
• Coastal
• Mountainous

Helsinki
Cabouw
Chilbolton
Lindenberg
Bonn
Oberpfaffenhofen
Palaiseau
Graz
Cevennes-Vivarais
Rome
Catalunya
7
GV in Snow Regions
Alps

• Snow is the dominant precipitation in
• Northern Scandinavia,
• The Alps.
• Accumulated snow is a major resource for fresh
  water hydro-powerthroughout all seasons and
  for wide areas.
• No previous experience with snow retrieval from
  TRMM.
• Scattering properties
• Raindrop shape is well (?) known, ? 1 g/cm³
• Snow has irregular shape, ? 0.05 1 g/cm³

Finland
8
Basic rainfall validation

• Dense rain gauge networks
• Example gauges available for the
  Mesoscale Alpine Project (MAP) 1999
• Radar networks (schematic)

Baltrad
9
Germany

• Different precipitation systems observed.
• 3 sites have potential to act for GV
• Lindenberg (DWD)
• Bonn (University)
• Oberpfaffenhofen (DLR)

10
Operational networks in Germany
rain gauge network
C-band Doppler radar network
about 4000 stations with 24h-accumulated
precipitation measurements
range130 km
Doppler-Radar
11
Instrumentation of Supersites

• The proposed supersites have excellent
  instrumentation and are well experienced in the
  development and operation of the systems and the
  organization of field campaigns.
• Radar systems (C, X, Ka, W - Band), scanning
  vertical pointing
• Multi-frequency radiometer systems
• Lidar systems, ceilometers
• Windprofiler, RASS, Sodar
• Surface observations
• Disdrometers, rain gauges
• Rain gauge networks
• Operational radio sondes nearby
• Lightning detection systems
• Research aircraft
• ...

12
Southern Germany

• Dense observation network
• 3 Doppler radars(2 polarimetric)
• Rain gauges
• Radiosondes
• Meteorologicalinstitutions in
• Munich
• Oberpfaffenhofen
• Hohenpeißenberg
• Garmisch-Partenkirchen
• Zugspitze

13
Munich-Alpine site

• OberpfaffenhofenDLR research site580 m MSL
• HohenpeißenbergDWD radarprecip.research
  site988 m MSL
• ZugspitzeGAW environmentalresearch site2960 m
  MSL

14
Current Networking in Europe

• Radar networks and rain gauge networks operated
  by
• National weather services,
• Regional weather services.
• International Networking through
• WMO,
• Network of European weather services EUMETNET,
• Network of European operational radar systems
  OPERA.
• Potential supersites are currently operated by
• national research organizations,
• some in cooperation with national weather
  services.
• Networking of supersites currently through
• Common EU projects likeCLIWANET, EuroTRMM,
  CLOUDMAP, ...

15
Concept of a distributed or virtual Supersite

• A distributed or virtual supersite will consist
  of
• Supersites in different climate regions,
• linked together by
• National weather radar networks.
• Benefits of a distributed or virtual supersite
• Synergy through different instrument set-up.
  Sites have different scientific background.
• Economic benefits, reduction of costs.
• Supersites will also allow for the assessment of
  the error structure of operational radar
  networks.
• Recommendations for radar gauge adjustment by
  weather services and users.

16
Concept of a distributed or virtual Supersite

• The concept is based on a networking
  infrastructure, both physical and organisational.
  
• Physical networking consists of the exchange of
  data, instruments and routines.
• Exchange of instruments for calibration and
  intercomparison campaigns.
• Mobile instruments for focus observation
  campaigns at any of the existing sites or in
  other regions of interest.
• Organisational networking is a structure where
  the participating site mangers, the national
  weather services and GPM representatives will be
  presented.

17
Concept of a distributed or virtual Supersite

• The concept of a distributed or virtual supersite
  will increase the observational area and thus
  increasing the number of satellite overpasses for
  various regions and precipitation systems.
• Through the networking activities it will be
  possible to provide a maximum of information even
  though not all sites are fully instrumented.
• Still many open questions . . . .? some will
  be addressed at working group 1