AMMA phase 2 and THORPEX-Africa Jean Philippe Lafore CNRM-GAME, Météo-France and CNRS, Toulouse,...
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Transcript of AMMA phase 2 and THORPEX-Africa Jean Philippe Lafore CNRM-GAME, Météo-France and CNRS, Toulouse,...
AMMA phase 2 and THORPEX-Africa
Jean Philippe Lafore
CNRM-GAME, Météo-France and CNRS, Toulouse, France
With thanksto the AMMA-International Scientific Steering Committee
and to the numerous participants to AMMA
WWRP-THORPEX African Regional Committee meeting8-10 May 2012, Geneva, Switzerland
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-10%
-20%
20%
10%
0
Wet period
Dry Period
The largest regional deficit of rainfall observed during the last centuryThe largest regional deficit of rainfall observed during the last century
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Uncertainties Uncertainties aabout the futurebout the future
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Climate Variability Impacts
WaterAgricultureHealthDemographicsSecurity
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Outline
1. AMMA project Some major outcomes of AMMA-1 Main objectives of AMMA-2
2. Current tasks in the THORPEX area Forecaster’s handbook NWP ISV
3. Conclusion
30th Conference on Hurricanes and Tropical Meteorology (15-20 April 2012)
Dry spells
Flooding: Ghana 07
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National Operational
ServicesRegional Centers
AMMA: An international program on West African monsoon variability and society-environment-climate interactions
Researchers
Societal needs
Forecasts/EWS
Observations
Scientific questions
Knowledge Models
Aim 1 To improve our understanding of the West African Monsoon
variability
Main contribution of AMMA phase 1 (2002-10)
THORPEX-Africa
Greater emphasisin AMMA-2
Aim 3 To ensure that the AMMA research is
integrated with prediction & decision
making activities (Forecast/EWS)
Aim 2To provide the underpinning
science to relate WAM variability to related societal
issues To define & implement relevant monitoring & prediction strategies
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Research field experiments / Database & library
Observation networks; Modelling; Satellite Products tailored & validated
Training/Education: PhD (160 incl 80 Africans!!) Masters, Summer Schools, Workshops
Communication (external & internal)
AMMA: Established an International Community
Coordination : Multidisciplinary, Different communitiesInternational : ~600 people from 30 countries
Africa : ~250 pers ; Research and Application (Forecast/EWS) communities
AMMA coordinated with international programmes and bodies
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Ewiem Nimdie Summer School - July 2008
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Multidisciplinary Observations 1400 questionnaires of a socio-economic studyNatural resources data
Géré à l’OMP
AMMA Bibliography
mirrored in Africa at AGHRYMET (Niamey)
Other projects: FENNEC, ALMIP2, ESCAPE,…
http://database.amma-international.orghttp://amma.agrhymet.ne
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Radiosoundings: A Major Achievement of AMMA
The AMMA radiosonde budget was about 2.5 M€The AMMA radiosonde budget was about 2.5 M€ Operational agencies in the region launched the great majority of these sondes. Around Operational agencies in the region launched the great majority of these sondes. Around 50% of these were the routine operational commitment, which has continued by and 50% of these were the routine operational commitment, which has continued by and large.large. A significant fraction of the data were not communicated to the GTS.A significant fraction of the data were not communicated to the GTS.
Funding issue to maintain a basic operational networkFunding issue to maintain a basic operational networkProject submitted to DG/Dev of EU (via SECAO) no newsProject submitted to DG/Dev of EU (via SECAO) no news
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Impact on TCWV Average over the period 1 Aug-14 Sep’06
Assimilation of AMSU-B over land
TCWV (EXP-CTL)
More humidity in EXP
TCWV diurnal cycle at TOMB
Karbou et al, 2009a, b
• Positive impact of the assimilation of AMSU over land• Large impact over Tropics in Monsoon regions• especially over Africa and in region with a poor data coverage• Improvement of the diurnal cycle
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Assimilation of AMSU-B over land
T (EXP-CTL)
Vz (EXP-CTL)
Karbou et al. 2009a, b
AEJ increase
évaluation AERES 15-17 janvier 2008EUMETSAT (28-30 June 2011)WMO RAI Dissemination Expert Group 2nd Meeting
Assimilation of AMSUB over land
24h
Karbou et al. 2009a, b
Smaller errors in EXP
48h72h
• Positive impact of the assimilation of AMSU over land
• Large impact over all Tropics on the wind field in the upper troposphere
Forecast errors versus ECMWF analyses (forecast–analysis) 200hPa Z, 1-31 Aug’06
Difference between EXP and CTR
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AMMA, ACMAD, Météo-France, OMM, Services Météo Nationaux Africains
New forecasting methods in Africa Knowledge transfer Researchers Forecasters
Outcome Example: Forecast for civil security (Aviation, Floods, etc)
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AMMA Forecast method: WASA/F
West African Synthetic Analysis/Forecast
List of the 10 key features to put
1. ITD 2. Heat-Low3. SubTrop Jet4. Trough from midlatitude5. TEJ6. AEJ7. Troughs and cyclonic centres associated to African
Easterly Waves (AEW) 8. Midlevel dry intrusions9. Monsoon layer
10. Convective activity:a. Suppressed convection b. Convection: isolated, MCS and Squall Lines
9 Provided by models
Other features
17
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WASA
19 July 2006 AT 0600Z
WASF from D-1 WASF from D-2
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AMMA Phase 2 (2010-2020)
Updated International Science Plan completed December 2010www.amma-international.org/IMG/pdf/ISP2_v2.pdf
Research Themes:(i) Interactions, Society, Climate(ii) Weather, Seasonal and Climate Predictability and
Prediction(iii) Monsoon System
Priorities• Capacity building• Aims 2 and 3 will receive greater emphasis in phase 2
WWRP-THORPEX African Regional Committee meeting8-10 May 2012, Geneva, Switzerland
THORPEX-Africa
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Forecasters’ Handbook for West Africa
The forecasters’ handbook aims to:– Document existing best-practice for the region– Import and test new ideas from other parts of the world;– Exploit new scientific results from AMMA (e.g. use of land-surface remote sensing
for daily to intraseasonal forecasting.
The project has formal WMO / WWRP / THORPEX-Africa support; ACMAD is leading the management
– Well structured (chapters, editotial committee…) – We hope to publish this as a commercial book (this option is preferred by the
African participants) – Target timescale for completion: 2013.
Lack of funding to support this project and more especially African contribution (short stays of African forecasters to elaborate materials)
– it’s not a text book (forecasting methods, Illustrations)– Case studies for training (AOC website already provides many examples)– Some support from NERC (only meetings)
WWRP-THORPEX African Regional Committee meeting8-10 May 2012, Geneva, Switzerland
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Evaluation of TIGGE and ECMWF forecast products over West and Central Africa
Collaboration: – LOCEAN (Janicot), ANACIM (N’Diaye), Cameroon (Kamsu)
TIGGE multi-models ensemble runs : forecasts at 15-day range– 2008-2012– Evaluation for all seasons of the main 15-day modes and MJO-mode over West
and Central Africa
ECMWF ensemble simulations at 45 and 60-day ranges– Hindcast over 1989-2008; ensemble runs : forecast twice a month (every fifteen
days, the first one at 45-day range, the second one at 60-day range)– Evaluation for all seasons of the main 15-day modes and MJO-mode over West
and Central Africa– Courtesy F. Vitard (ECMWF)
WWRP-THORPEX African Regional Committee meeting8-10 May 2012, Geneva, Switzerland
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Real-time monitoring and forecast of intraseasonal variability ISV
Major progresses during the last decade in documenting and understanding the African ISV
3 main timescales:
25-90 days:
– link to the MJO (e.g. Matthews 2004, Janicot et al. 2009)
10-25 days:
– Quasi-Biweekly Zonal Dipole (QBZD, Mounier et al. 2008)
– Sahelian mode (Janicot et al. 2010),
– Variability of the Saharan Heat Low and link with midlatitudes (Chauvin et al. 2010, Roehrig et al. 2011)
3-10 days:
– African Easterly Waves (e.g. Kiladis et al. 2006),
– Synoptic variability of precipitable water (Couvreux et al. 2010, Poan et al. 2012),
– Kelvin waves (Mounier et al. 2007) Objectives:
– Confront the climatology to the real world;
– Investigate the forecast skill of the monsoon ISV, based on our current knowledge
Approach:
– Address these 2 points through a real-time exercice
10-25 days: Sahelian mode
OLR
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Project « ISV-monitoring »
Collaboration between France & Senegal (ANACIM, LPAO-SF): involving forecasters
– Started in 2011– Monsoon season JJAS
A real-time website, simple but easily and rapidly evolving, according to the encountered needs and ideas
Use of websites providing complementary information (broader context)
– e.g. MJO: Wheeler’s website + NCEP
Regular briefing & reports (~2/week) between Toulouse and Dakar.
http://isv.sedoo.fr
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fdb
HLE – 7 June “Canonical” HLE
Km s-1
“Canonical” HLWHLW – 16 June
Km s-1
Shading: θ850 anomaliesBlack contours: raw θ850
Vectors: wind anomalies at 850 hPaGreen contours: raw sea level pressure
High similarities with canonical events: they make sense in the “real world”
Overview of 2011 ISV: 10-25-day scale
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3 HLE events: 5-9 June, 18-24 July, 1-4 Sep
4 HLW: 12-18 June, 25 June-1 July, 10-14 Aug,7-10 Sep
The season begins with a HLE event, favorable to the monsoon onset (Roehrig et al. 2011)
Heat Low intraseasonal index
HLE1 HLE2 HLE3
HLW1 HLW2 HLW3 HLW4
HLW5
HLE4
Overview of 2011 ISV: 10-25-day-scale
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PW anomalies [12N-20N]
kg m-2
Synoptic Variability of Precipitable Water (PW)
Overview of 2011 ISV: 1-10-day scale
High correlation (0.57) between precipitation and PW over Senegal, especially after the monsoon onset (0.63).
High potential of the PW variable
PW anomalies Rain gauge precipitation
PW a
nom
alie
s (k
g m
-2)
Precip (mm
day-1)
June July August Sept
Precipitable Water index and Rainfall: over Senegal
Same characteristics as the canonical mode: frequency, propagation Differences between the eastern and the western Sahel structures (as in Poan et al 2012)
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Conclusion for the « ISV-monitoring »
Conclusions: – 10-25 days
• Monitoring of heat low variability provides some large-scale information on the monsoon system. The relationship with the onset (Roehrig et al. 2011) seems to work this year
• The monitoring of the QBZD and Sahelian modes is less obvious (not shown).
– Synoptic scales:• PW has a large potential: high predictability, strong relationship with
precipitation.
Future:– New exercise in 2012: with new diagnostics and with higher involvement of
Senegalese forecasters– Quantitative evaluation of:
• Diagnostics (e.g., filtering effects)• Skills of ECMWF forecasts for different scales(PW, Heat Low…)
WWRP-THORPEX African Regional Committee meeting8-10 May 2012, Geneva, Switzerland
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• AMMA will continue:- To mobilize, reinforce & coordinate the African & international communities working on the West African monsoon and its societal impacts.
- To combine Observations, Forecasts, Capacity building, Knowledge transfer to better anticipate and mitigate the human (and natural) impacts of weather and climate variability
• Challenges to consolidate AMMA-Africa - To strengthen * visibility and support regionally & in each country * collaboration between research & application communities * integration of African PhDs in research & application
(NHMS/EWS) centers
- To maintain & improve observation network to forecast & monitor weather and climate variabilities and its impacts
Final Thoughts