Download Seasonal Outlook Briefing

Bureau of Meteorology Activities as
a GPC of Long Range Forecasts
Dr David Jones
[email protected]
Australian Bureau of Meteorology
CBS Expert Team on Extended and Long Range
Forecasting
Geneva, Switzerland, 26-30 March 2012
Acknowledgement
Oscar Alves, Andrew Watkins, Lynette Bettio, Elise Chandler &
Andrew Charles
Long Range Forecast Service
Delivering useful long range predictions for Australia and
WMO member countries
• Current seasonal outlooks for Australia based on a statistical
model
• Probability of rainfall/temperature in Tercile/Above Below Median
categories
• Trial of dynamical model forecasts.
• Statistical monitoring and prediction of Intraseasonal
Variability
• Current phase and amplitude of the MJO
• Prediction for winds, rainfall, convection, pressure for the coming
weeks
• Dynamical model predictions for ocean conditions &
experimentally for climate variables over land
• Focus on the Pacific and Indian Oceans
• Developing direct model forecasts for rainfall and temperature
Recent POAMA 2.4 improvements
• POAMA2.4 became fully operational in October 2011
• T47L17 + improved physics (land surface, radiation, gravity wave
drag, cloud microphysics, etc)
• Land surface scheme (ALI) is more realistic and initialized daily
• Increased number of ensemble members of hind-cast (30 member)
over the last 30 years (updated in real-time), providing better
hindcast skill estimates
• Real-time forecasts (30 ensemble members per month) since July
2011 run twice monthly. Moving to a 1981 to 2010 base period
• Improved accessibility – OpenDAP server
http://opendap.bom.gov.au:8080/thredds/bmrc-poama-catalog.html
• Pseudo multimodel ensemble
The Coupled Model: Predictive Ocean
Atmosphere Model for Australia
POAMA
=
BoM
Atmospheric
Model (BAM) v3
+
Australian
Community
Ocean Model
(ACOM) v2
+
Simple
land-surface
model
• POAMA=Predictive Ocean Atmosphere Model for
Australia
• Forecasts run for 9 months
• Atmospheric model:
• Horizontal resolution ~250km
• 17 vertical levels
• Ocean model:
• Zonal resolution ~220 km
• Meridional resolution ~55km (tropics) to ~165 km (poles)
• 25 vertical levels
Plans for POAMA/ACCESS versions
Operational P2.4 Full
Seasonal System
P2.4
M2.4
Enhanced
ensemble
generation
M2.4 multi-week
system in
operations
M2.4 Seamless Multi-week/First
Seasonal only System in
operations
?
Done
Future
Operational M2.4 Seamless
Multi-week/Full Seasonal
System
P2.5
Coupled
DA/ensemble
generation
Operational P2.5
multi-week system in
operations (may
bipass)
~1-3 months
~6-9 months
Operational P2.5
Seamless
multiweek/seasonal
~6-12months
P3.0
ACCESS Based
higher resolution
system
Operational P3.0
multi-week system
~2 years
Operational P3.0
Seamless
multiweek/seasonal
~4 years
Public
Website
Operational Products:
SSTs, NINO 3,3.4,4 & IOD available
Pacific SST skill: Temporal correlation of
monthly SSTA
Correlation
POAMA-2
POAMA-1.5
Forecast Lead time (months)
ECMWF
System 3
Frontier
Research Centre
Model (Japan)
NCEP Climate
forecast system
V1 & 2
POAMA 1.5 & 2
Correlation
with
(CMAP) Rainfall
POAMA skill
- Rainfall
How well does POAMA do with the rainfall patterns?
Highest correlation is found in the equatorial Pacific and
parts of the southwest Pacific…..
Predicting the MJO Index
MJO index forecast skill (RMSE = 1.4)
POAMA-2 (m24m)
POAMA-1.5
POAMA-2
POAMA-1.5 (p15b)
SON
Season
JJA
MAM
DJF
ALL
1
3
5
7
9
11
13
15
17
19
21
23
25
27
Lead time (days)
Skillful prediction of the MJO out to….
All seasons:
29
Producing Reliable Forecasts:
Calibration
Raw rainfall forecasts (lower
Tercile) across the tropical
Pacific
Calibrated (IOV) forecasts –
better reliability but lower
skill.
Architecture for Seasonal Forecast
Generation and Publication System
The Bureau as a GPC
Hindcasts verified
following the LRFVS
Real time forecasts
Developing a GPC Seasonal
Prediction Portal
The Seasonal Prediction Portal provides access to outlooks for
• Broad scale fields
• Climate drivers (ENSO)
• Rainfall and temperature tercile probabilities for selected
sites
• Hindcast skill scores for all outlooks
• Focus on the Pacific
http://poama.bom.gov.au/experimental/pasap/
Capacity Building
• Extensive training of the Pacific NMS personnel during
in-country visits
•PASAP/PI-CPP joint workshops – Auckland, New
Zealand (Sept 2010) and Port Vila, Vanuatu (Sept 2011)
The Bureau as a GPC
•
•
•
•
The BoM is a producer of LRFs, following a fixed time schedule
Products are available to other GPCs, RCCs and NMHSs
Forecasts provided to the LRF Lead Centre and APCC
Hindcasts have been verified following the Standardized
Verification System
• Systems are scientifically documented
• The Bureau does not yet have a GPC website
• The BoM is heavily involved in training and capacity building
activities in the South Pacific:
• Pacific Islands Climate Prediction Project
• Pacific Adaptation Strategy Assistance Program (delivering
dynamical season outlooks for Pacific Island countries)
• Pacific Climate Change Science Program
• Opportunity for additional supported projects
• Developing forecasts for extreme events – TCs, Coral
Bleaching, high sea level