Transcript model output statistics and climate variability over

ARIAL PROGRAMME ON REGIONAL CLIMATE
VARIABILITY AND CHANGE MODELLING OVER
THE NIGERIAN ZONE OF WEST AFRICA
Imoh B. Obioh
Atmospheric Research and Information Analysis Laboratory
(ARIAL)
Centre for Energy Research and Development (CERD)
Obafemi Awolowo University, Ile-Ife, Nigeria
Workshop on Theory and Use of Regional
Climate Models, ICTP, Trieste, 26 May - 6 June
2003
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Motivation
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Strong Climate System Drivers
Evidence of Some Systematic Climate System
Evolution – portraying “change”
Likely high vulnerability of many life support
systems, and observed low capacity for early
warning and adaptation
Need to:
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Improve understanding of regional climate system physics
Contribute to global scientific efforts on climate change
Provide framework for mitigation and adaptation
Integrate climate change issues into national economic
medium to long term planning
Workshop on Theory and Use of Regional
Climate Models, ICTP, Trieste, 26 May - 6 June
2003
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CHALLENGES
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Low and decreasing density of (especially
younger) scientists (below NVP for survival)
Poor research, auxiliary infrastructure and
local financial support – increasing tendency
of work-sleep approach to research
Poor network of the limited infrastructure
and people – little team work approach
Workshop on Theory and Use of Regional
Climate Models, ICTP, Trieste, 26 May - 6 June
2003
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OBJECTIVES OF ARIAL
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OVERAL OBJECTIVE
– Basic Meteorology and Climatology
– LOWER AND UPPER ATMOSPHERIC PHYSICS AND
CHEMISTRY
– Biosphere-Atmosphere Interactions
– Air Pollution Research
– CLIMATE CHANGE ASSESSMENT:
GHG Inventories
 Mitigation Analyses
 Regional Climate Modelling
 Development of Climate Change Scenarios
– Computational Sciences and Model Development
– Information Sharing/Dissemination
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Workshop on Theory and Use of Regional
Climate Models, ICTP, Trieste, 26 May - 6 June
2003
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OBJECTIVES OF ARIAL
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RCM OBJECTIVE
– Improved Understanding of Physical
Climate System in the Sub-Region
– Provision of New Data for Impact
Assessment, Planning and Public
Education
– Human Capacity and Support
Infrastructure Development
– Contribution to global efforts
Workshop on Theory and Use of Regional
Climate Models, ICTP, Trieste, 26 May - 6 June
2003
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CURRENT RCM EFFORTS
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DEVELOPMENT OF DOWNSCALING
TECHNIQUES
Based on need to:
Sensibly project large-scale information on the regional
scale (von Storch et al., 1993).
•Estimate local climate variability from the global scale.
Workshop on Theory and Use of Regional
Climate Models, ICTP, Trieste, 26 May - 6 June
2003
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CLIMATE OF WEST AFRICA
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ITD/ITCZ (10 -20oLat):
MJJAS
Monsoon winds (850 – 700
hPa)
Upper level Winds (Jets )
– AEJ (500-600 hPa)
– TEJ (200 hPa)
Workshop on Theory and Use of Regional
Climate Models, ICTP, Trieste, 26 May - 6 June
2003
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STATISTICAL DOWNSCALING
Model Output Statistics uses:
Empirical Orthogonal Functions (EOF)
PREDICTORS from ECHAM
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Zonal wind at 850 hPa
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Zonal wind at 700 hPa
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Precipitation
PREDICTAND:
Monthly mean precipitation data (Nigerian
Meteorological Agency)
Workshop on Theory and Use of Regional
Climate Models, ICTP, Trieste, 26 May - 6 June
2003
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RAINFALL CORRELATIONS: ECHAM VS
OBS.(JAS)
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Horizontal resolution 
300 km
18 Levels in the
Vertical
Need to Downscale to
50 km horizontal
Resolution
Workshop on Theory and Use of Regional
Climate Models, ICTP, Trieste, 26 May - 6 June
2003
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NIGERIA: 33 SYNOPTIC STATIONS USED
IN STUDY
Workshop on Theory and Use of Regional
Climate Models, ICTP, Trieste, 26 May - 6 June
2003
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JAS RAINFALL AVERAGE
Workshop on Theory and Use of Regional
Climate Models, ICTP, Trieste, 26 May - 6 June
2003
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NIGERIA INTERANNUAL RAINFALL
VARIABILITY DURING JAS
Workshop on Theory and Use of Regional
Climate Models, ICTP, Trieste, 26 May - 6 June
2003
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PRELIMINARY RESULTS
PRECIPITATION SKILL MAP
Workshop on Theory and Use of Regional
Climate Models, ICTP, Trieste, 26 May - 6 June
2003
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700hPa U-WIND SKILL MAP
700hPa
850 hPa
Workshop on Theory and Use of Regional
Climate Models, ICTP, Trieste, 26 May - 6 June
2003
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SUMMARY
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MOS Results still preliminary, not yet
satisfactory.
Appreciable skill levels obtained from model,
can be improved upon
Despite poor MOS, downscaled results still
agree more with Observed than GCM results
in most cases.
Workshop on Theory and Use of Regional
Climate Models, ICTP, Trieste, 26 May - 6 June
2003
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NEXT STEPS
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Improved MOS for Application over 1961-2000 and
2000-2100 time scales
Engagements in Other RCM Techniques:
– Dynamical Downscaling
– RegCM
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Improved Understanding of Regional Model Physics
and Climate Sub-Systems’ Evolution
Provision of Data
Increased Human Capacity/Infrastructure
Development
Sustainability of RCM and Other CC Initiatives
Workshop on Theory and Use of Regional
Climate Models, ICTP, Trieste, 26 May - 6 June
2003
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FRAMEWORK
COLLABORATION:
A KEY AVENUE TO
FULFILLING MOST OF THESE
Workshop on Theory and Use of Regional
Climate Models, ICTP, Trieste, 26 May - 6 June
2003
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ACKNOWLEDGEMENTS
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Canada-Nigeria Climate Change Capacity Development Project
(CN-CCCDP) supported with from CIDA, through GCSI, Canada;
NEST, Nigeria; and Fed. Ministry of Environment, Abuja.
International Research Institute for Climate Prediction (IRI),
Columbia University, Palisades New York, USA
African Regional Centre for Space Science and Technology
Education, Ile-Ife, Nigeria.
Workshop on Theory and Use of Regional
Climate Models, ICTP, Trieste, 26 May - 6 June
2003
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THANK YOU
Workshop on Theory and Use of Regional
Climate Models, ICTP, Trieste, 26 May - 6 June
2003
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