Experimental POAMA-1.5 SST Anomaly Forecasts
The following plots show the LATEST experimental
sea surface temperature anomaly (SSTA) forecasts for the coming months in the Great Barrier Reef (GBR), Australia.
Figures 1 and 2 show the SSTA forecasts using an ensemble of daily
forecasts from the past 30 days and past 10 days, respectively.
Figure 3 indicates probabilities of forecast SSTA (30 day ensemble) exceeding 0.6C
in that month. Figure 4 indicates corresponding model skill for each lead time.
Figure 1. SSTA forecast: 30 member ensemble
Figure 2. SSTA forecast: 10 member ensemble
Figure 3. Probabilistic forecast: SSTA >= 0.6 C
Figure 4. Skill of SSTA forecast
Forecasts are generated from POAMA-1.5 at lead times of 0-5 months for the region. SST anomalies are calculated as the difference between SST values and the climatology, the monthly long term mean SST. Plots are updated daily and are based on the ensemble mean of the last 30 daily forecasts. Information from these 30 forecasts can also be used to determine the likelihood or probability of an event occurring, e.g. SSTA exceeding a particular threshold, which is useful for management applications. Plots based on the ensemble mean of the last 10 forecasts are also presented to highlight any events in the system (e.g. monsoon onset, tropical cyclones) that may have occurred in the past week or so.
To evaluate the accuracy of model forecasts and provide a measure of the skill of the model, hindcasts of SSTA are compared to observed SSTA for the same period. Skill is calculated by correlating model anomalies with observed anomalies in both space and time. Information on spatial and regional average skill is provided on the following page:
Skill of GBR SST forecasts. For further details see Spillman and Alves (2009).
Summaries of POAMA SST predictions and model performance for 2008/2009 and 2009/2010 are available in the CAWCR Research Letters.
GBR Index Ensemble Distribution
The following plot shows the distribution by quartiles of the ensemble composed of the last 30 forecasts for SST anomalies averaged over the Great Barrier Reef region. The ensemble distribution gives a sense of the certainty of the forecast, and of the relative probabilities of various outcomes. The shading indicates upper and lower climatological terciles from the POAMA-1.5 hindcasts.
Experimental POAMA-1.5 Forecasts in Google EarthTM
Extended experimental POAMA forecasts for the tropical oceans (30S-30N) can now also be viewed in Google EarthTM.
Available products include:
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POAMA-1.5 Experimental Products
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Google Earth Files
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Latest real-time forecasts:
SSTA for leads 0-5 months
Probability of SSTA >= 0.6C
Degree Heating Months (DHM)
Probability of DHM >= 2.0
SSTA Skill for leads 0-5 months
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Web Version (V1.1)
(1 October 2010)
(kmz file; compressed: 3 KB)
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Model skill (based on 1982-2006):
SSTA skill for leads 0-5 months
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Web Version (V1.0)
(27 September 2010)
(kmz file; compressed: 3 KB)
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Hindcasts for 1982-2006:
SSTA for leads 0-5 months
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Web Version (V1.0)
(17 September 2010)
(kmz file; compressed: 18 KB)
Offline Version (V1.0)
(17 September 2010)
(kmz file; compressed: ~31MB)
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Hindcasts for 1982-2006:
Degree Heating Months (DHM)
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Web Version (V1.0)
(17 September 2010)
(kmz file; compressed: 5 KB)
Offline Version (V1.0)
(17 September 2010)
(kmz file; compressed:~4MB)
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To view these products, you must first have downloaded and installed
Google EarthTM on your computer.
Google EarthTM is free and available from
http://earth.google.com/. To view the online versions of our products,
you require an internet connection to access the forecast images.
Click on the link to the .kmz file above to launch Google Earth
TM and view files.
For our offline versions, you may download complete packages containing
program files and images to view in Google EarthTM
without an internet connection. To save the file to you computer, first right click on the offline link and save the file to a local drive as a .kmz file. Click on the .kmz file
(or the .kml file inside if the zip file opens) to launch
Google EarthTM and view files.
This approach is recommended for the hindcast products in the case
of repeated viewing.
Viewing Instructions:
- In the 'Places' panel on the left side of the Google
EarthTM window,
find the POAMA forecast product folder under 'Temporary Places.'
- To check for latest or updated forecasts, right click on the
network link (folder) icon and select Refresh.
- Click on the box(es) next to the desired subfolder and data layer
to display them in the earth viewing window.
- To loop through lead-times for the SSTA, SSTA>0.6 and skill products,
click on the clock on the time slider at the top of the earth viewing window.
For information about using the time slider, see here.
- Details on each product can be found by clicking on the link
'About These Products' below the product folders.
- For the hindcasts, click on the product folder to expand the folder
to see the hindcast dates available for viewing.
- If the full Google EarthTM display can
not be seen (including logos),
please modify your screen resolution (minimum 1280x1024). More information on system requirements available here.
For assistance with Google EarthTM,
please see support.
Please note that only the 1st of each month is available in the archive.
More POAMA Forecasts
Useful Links
