David B. Parsons
School of Meteorology
University of Oklahoma
1
Based on a paper in preparation for submission to the Bulletin of the
American Meteorological Society by Parsons, Shapiro and many
others
The article proposal has been accepted and a first draft with holes
should be completed in ~2 weeks.
2
Background
 The 10-year THORPEX era is coming to a close (e.g., “initiated” by the
WMO in 2003 and “implemented” in 2005)
 The Executive Committee of the THORPEX International Core Steering
Committee (ICSC) has asked me to lead an effort to formally document the
scientific and operational outcomes of the program, including the
challenges faced through an article in the refereed literature
 A plan for an article to be submitted to the Bulletin of the American
Meteorological Society (BAMS) was approved by the THORPEX ICSC
followed by a proposal submitted to and approved by the BAMS editorial
staff
 Numerous scientists involved in THORPEX are contributing text and more
will contribute by reviewing the document for accuracy.
3
Background
 Numerous scientists involved in THORPEX are contributing text and more
will contribute by reviewing the document for accuracy. Note on authors
and strategies………..
--- Lead authors selected for various sections
--- Selection of lead authors depends heavily on discussions at ICSC (and
current WG co-chair roles)
--- Lead authors suggest others that made important contributions and
should to be included
---- Other researchers critical to THORPEX effort will be included and
asked to review the document
---- We will be inclusionary
4
Outline
1. Introduction – History, goals, objectives and organization – Mel Shapiro
2. Research to advance the components of numerical weather prediction
systems
3. Global-to-regional aspects of high impact weather: regional campaigns
4. THORPEX from the poles to the equator
5. Broader impacts (collaborations, training, meetings, etc)
6. A legacy of improvements to operational prediction and forecasting
7. Lessons Learned and Challenges Faced
8. Conclusions and the THORPEX legacy projects
5
2. Research to advance the components of
numerical weather prediction systems
a) Insight into the global observing system – Mujumdar,
Langland and Hamill--An evaluation of adaptive measurement strategies
b) Advancing data assimilation – Saunders, and Rabier
Furthering ensemble-based assimilation techniques and
promoting new techniques for data impact studies
c) Ensemble prediction – Swinbank and Bougeault
Creating the TIGGE data base, subsequent research
and regional examples (TIGGE-LAM, NAEFS and S.
American efforts)
7
2. Research to advance the components of numerical
weather prediction systems
a) Insight into the global observing system – The basis of this section is the WMO report
produced by Majumdar et al. 2011) summarizing a decade of Observation System Experiments
and forecast sensitivity studies associated with THORPEX were:
i. The value of extra-tropical targeted data was positive, but small on average;
ii. Adaptive observations sampled around tropical cyclones improved track forecasts;
iii. Observations taken in sensitive areas had more value than those deployed randomly;
iv. The value of adaptive observations depended on the modeling and assimilation;
v. Adaptive processing and selection of satellite data, particularly on larger spatial and temporal
scales than are achievable by aircraft, can be a cost-effective solution.
Recent evaluation of the impact of targeted observations during NOAA’s 2011 Winter Storm
Reconnaissance program found neutral impact (Hamill et al. 2013).
The average marginal impact of an individual observing system is decreasing, and therefore an
ongoing assessment of the cost-effectiveness of targeted (and routine) observations is
necessary.
8
3. Global-to-regional aspects of high impact weather:
regional campaigns
a) High impact weather in the Mediterrean (HYMEX) -- Ducrocq
Knowledge of atmospheric and hydrological influences that lead to flash floods,
development of improved coupled modeling systems and data assimilation
strategies on convection permitting-scales
b) West African Monsoon (AMMA) – Redelsperger and Thorncroft
Advancing observational strategies (rawinsonde and satellite) over West Africa
and knowledge of data impacts, dynamics of African Easterly waves, tropicalextratropical interacts -- NASA collaboration, THORPEX role limited to WG2
-
c) Tropical cyclones and extra-tropical transitions (T-PARC and related tropical cyclone
experiments) – Harr, Jones, and Nakazawa with ONR in a major way
Knowledge of tropical cyclone targeting in the N. Pacific basin, understanding
and advances in prediction of tropical cyclone genesis, and ET dynamics and
forecast failures
9
4. THORPEX from the poles to the tropics
a) Weather and climate in polar regions (including THORPEX-IPY cluster) – Brunet
and Rabier --- probably THORPEX’s largest effort
b) Middle latitude dynamics --- Davies, Wernli and Szunyogh
c) Year of Tropical Convection (YOTC) – Moncrieff and Waliser
10
4. THORPEX from the poles to the tropics
Weather and climate in polar regions (including THORPEX-IPY cluster)
Concordiasi Antarctic project--- Rabier et al. (2010) – use of driftsonde and long duration
ballooning, cold bias in all satellite data with inversions under estimated, identification
of errors in model physics, ensemble data assimilation for AMPS, etc
THORPEX Arctic Weather and Environmental Prediction Initiative (TAWEPI) -improvement/implementation/evaluation of detailed dynamical-thermodynamic seaice coupled with ocean currents and snow models over the Arctic basin has been
peformed (Chung et al., 2010, 2011), evaluate regional weather prediction model (e.g.
Deacu et al., 2011) and the use of satellite observations (Garand et al., 2011) in the Arctic
Greenland Flow Distortion Experiment – Renfrew et al. (2008) see special issue of QJRMS
for scientific results
The Storm Studies of the Arctic (STAR) included enhanced observations in the eastern
Canadian Artic, gap flow, air-sea interactions, orographic precipitation, interaction of
cyclones with topography (Hanesiak et al., 2010).
11
5. Broader impacts
a) WCRP, GEO collaborations, training, workshops, symposiums etc) – Caughey and
Nakazawa
b) Enhancement in university and operational collaboration – Parsons and Jones
c) PANDOWAE: a national example --- Jones
d) Socio-economic research and applications – Mills and Rogers
12
6. Examples of legacy impacts on operational
prediction
a) North American Ensemble Forecast System - Toth et al
b) Hybrid data assimilation system in the US (NOAA THORPEX) – Wang et
al.
c) TIGGE as a bench mark for improving individual systems – Martin (?)
d) Legacy of high resolution polar prediction models (Env Canada and
CONCORDIASI AMPS in the US) -- Gilbert and Charron for Env Canada and
Parsons and Cavallo for AMPS
e) Tropical cyclone predictions, real-time ensemble products – Nakazawa et
al
f) THORPEX Africa and the forecasters handbook -- Parker and Diongue et al.
13
7. Challenges and lessons learned
a) Difficulty in making a difference in the developing world (should have tried to bring in
sponsors early --- USAID, European Commission, WHO, NGOs, etc??)
b) Changes in program managers (loss of Jay Fein and David Rogers) and varying
commitment of science leads) contributing to a small grant pool? -- need long-term
commitment higher in the agencies??
c) Funding agencies do not seem to be designed to handle such a cross-cutting project
(easy to obtain field project funding, hard to get funding for focused scientific
objectives, stove piping in agencies – all needs to be fixed for next time)
d) Interagency coordination is better than now, but could have been better and may have
slowly unraveled with time?
e) Difficulties integrating social science research into THORPEX
f) Certain communities (e.g., large-scale dynamics) tend not to work together on large
projects) Has that has changed – T-NAWDEX-- Downstream, wx ready nation?
g) Conflicts among scientists and scientific camps did occur, but perhaps less than
expected
14