Seasonal Climate Outlook Message for March to June 2003

The bottom line

SOI In "Falling Phase"

Dave McRae DPI Centre for Predictive and Precision Research 04/03/03

The 30day average of the SOI as of the 3rd March is minus 8.4. Based on the shift in monthly SOI value from January (minus 2) to February (minus 9.3) the SOI is in a "Rapidly Falling" phase.

This gives a somewhat mixed seasonal outlook across Queensland for March to May. For the Queensland/New South Wales border region west of Goondiwindi there has been a slight lift in the chance of getting above median rainfall to around 50-70%. However for the rest of the state the chance of above median rainfall for the same period has fallen slightly to around 20-40%.

For example, there is a 60% chance of getting above the long term March to May median rainfall of 95mm at Bollon. This compares with a 33% chance of getting above long term median rainfall of 68mm for the same period at Winton.

While the seasonal outlook does indicate the potential for continuing relief rain there remains only a relatively low chance of getting the widespread well above average rainfall events needed to break the Queensland drought pattern.

For those interested the latest rainfall probability maps can be found at www.dpi.qld.gov.au/climate or at www.longpaddock.qld.gov.au

As always when dealing with a probability based forecast system it is important to consider the alternate view. For example, currently there is a 22% chance of getting above 140 mm at Charters Towers. This also means there is a 78% chance of not getting above 140mm.

Another way of looking at this is that in 2 years out of 10 (or around one quarter) with the current SOI pattern, Charters Towers has received more than 140mm for March to May. Therefore in 8 years out of 10 (or around three quarters) with the current SOI pattern, less than 140mm has been recorded at Charters Towers.

Other years that have had a "Rapidly Falling" SOI phase in February include 1990, 87, 86, 82, 78, 73, 62, 57, 54, 53, 35, 31, 26, 16, 12, 05 and 1902. It can be very useful to find out what rainfall patterns and farming conditions where like for March to May in your area for those years.

For more specific climate information for your location refer to Australian Rainman, the latest "Climate Note" at www.dpi.qld.gov.au/climate or ring the DPI Call Centre on 13 25 23.

The full story

Climate Watch Dated 03/03/03

The 30day average of the SOI as of the 3rd March is minus 8.4. Based on the shift in monthly SOI value from January (minus 2) to February (minus 9.3) the SOI is in a "Rapidly Falling" phase.

This gives a mixed seasonal outlook across Queensland for the next 3 months (for March to May). There has been a slight lift in the chance of getting above median rainfall for the Queensland/New South Wales border region west of Goondiwindi. However for the rest of the state the chance of above median rainfall for the same period has fallen slightly.

For example, there is a 60% chance of getting above the long term March to May median rainfall of 95mm at Bollon. This compares with a low 33% chance of getting above long term median rainfall of 68mm for the same period at Winton.

While the seasonal outlook does indicate the potential for continuing relief rain there remains only a relatively low chance of getting the widespread well above average rainfall events needed to break the Queensland drought pattern.

There has also been a slight lift in the chance of above median rainfall for March to May across NSW and Tasmania. For much of the rest of Australia the chance of above median rainfall remains relatively low at around 30-40%.

The latest rainfall probability maps can be found at www.dpi.qld.gov.au/climate http://www.dpi.qld.gov.au/climate> or at www.longpaddock.qld.gov.au http://www.longpaddock.qld.gov.au>

As always when dealing with a probability based forecast system it is important to consider the alternate view. For example, currently there is a 22% chance of getting above 140 mm at Charters Towers. This also means there is a 78% chance of not getting above 140mm.

Another way of looking at this is that in 2 years out of 10 (or around one quarter) with the current SOI pattern, Charters Towers has received more than 140mm for March to May. Therefore in 8 years out of 10 (or around three quarters) with the current SOI pattern, less than 140mm has been recorded at Charters Towers.

As rainfall probabilities and median rainfall levels vary throughout the year and from location to location, we recommend referring to Australian Rainman for more specific rainfall data. Alternatively contact QCCA through the DPI Call Centre on 13 25 23.

Other years that have had a "Rapidly Falling" SOI phase in February include 1990, 87, 86, 82, 78, 73, 62, 57, 54, 53, 35, 31, 26, 16, 12, 05 and 1902. It can be very useful to find out what rainfall patterns and farming conditions where like for March to May in your area for those years.

Much interest has been shown in the intra-seasonal oscillation (or MJO) over the past year as an indicator as to the timing of potential rainfall.

The MJO is simply a band of low atmospheric pressure originating off the east coast of central Africa travelling eastward across the Indian Ocean and northern Australia roughly every 30 to 50 days. While it is a tropical phenomenon, it appears to indicate the timing of potential rainfall events (but not indicate rainfall amounts) over central and southern Queensland.

It should also be remembered that while promising, the use of the MJO as a reliable forecast tool is still at the research/experimental stage. The last passage of the MJO occurred around mid-February triggering some widespread but patchy storm and rain activity. It is next due in late March.

An El Nino pattern is still persisting in the central Pacific. While there is increasing optimism that this pattern is breaking down, all indications suggest that it will linger through to mid/late autumn. We will continue to monitor the situation and provide information as soon as there have been some significant changes.

It's worth pointing out that even if the El Nino pattern breaks down at the end of autumn, conditions may not improve in all areas for several months as unfortunately the breakdown of major drought events rarely occurs evenly across all affected areas.

Previous El Nino events include autumn 1902 to autumn 1903, 1905/06, 1911/12, 1913/14, 1914/15, 1919/20, 1925/26, 1940/41, 1941/42, 1946/47, 1951/52, 1957/58, 1964/65, 1965/66, 1969/70, 1972/73, 1977/78, 1982/83, 1987/88, 1991/92, 1993/94, 1994/95 and 1997/98. For planning purposes it may be helpful to find out when conditions improved in your area following these events?

Despite the generally welcome rain during February the number of Queensland shires drought declared under state drought processes continues to increase.

As of the 20th February there were 89 shires and 6 part shires declared under state processes. There area represents approximately 63.7% of the State. There are also 281 Individually Droughted Properties (IDPs) in a further 19 shires.

This area includes the Aramac, Atherton, Balonne, Barcaldine, Barcoo, Bauhinia, Beaudesert, Bendemere, Belyando, Biggenden, Blackall, Boulia (part shire), Boonah, Booringa, Bowen, Brisbane, Broudsound, Bulloo, Bungil, Caboolture, Caloundra, Cambooya, Cooloola, Chinchilla, Clifton, Crow's Nest, Dalby Town Council, Dalrymple (part shire), Diamantina, Duaringa, Eacham, Eidsvold, Emerald, Esk, Flinders (part shire), Fitzroy, Gatton, Gayndah, Gold Coast, Herberton, Ilfracombe, Inglewood, Ipswich, Isisford, Jericho, Jondaryan, Kilcoy, Kilkivan, Kingaroy, Kolan, Laidley, Livingston, Logan, Longreach, Mackay, Maroochy, McKinlay (part shire), Millmerran, Mirani, Monto, Mount Morgan, Mundubbera, Murgon, Murilla, Murweh, Nanango, Nebo, Noosa, Paroo, Peak Downs, Perry, Pine Rivers, Pittsworth, Quilpie, Redcliffe, Redlands, Richmond (part shire), Rockhampton, Roma Town Council, Rosalie, Sarina, Stanthorpe, Tambo, Tara, Taroom, Tiaro (Divisions 2 and 3), Toowoomba, Waggamba, Wambo, Warroo, Warwick, Whitsunday, Winton, Wondai and Woocoo.

In Queensland, the Primary Industries Minister makes drought declarations based on recommendations from Local Drought Committees. IDP status is granted when criteria related to rainfall, pasture and stock conditions are met. Shire declarations occur when the numbers of IDPs become too great to administer effectively.

Information on the current drought situation and available financial assistance, drought planning advice and social and community services can be found on the internet site www.dpi.qld.gov.au/drought/ http://www.dpi.qld.gov.au/drought/> or through the DPI Call Centre on 132523.

As part of the QCCA science program an experimental climate forecast system has been developed based on the pattern of tidal forces exerted by the Sun and Moon. Analysis suggests that tidally derived cycles may contribute to climate features like the Southern Oscillation and Pacific equatorial SSTs. Since the pattern of tidal force is predictable for centuries to come, any such connection would have obvious significant effects on our ability to forecast climate patterns. For more information try http://www.dpi.qld.gov.au/climate/9470.html>

Many producers and industry groups are interested in how climate forecasts can be used in management decisions. Some interesting case studies developed by the Climate Variability in Agriculture Program (CVAP) can be found at http://www.cvap.gov.au/mastersoftheclimate/>

These case studies highlight how some producers have used climate information in their management decisions and are well worth reading.

Many producers have also found it beneficial to do a cost benefit analysis of any decisions with a climate risk factor. For example, what will I gain if I get the desired outcome from this decision? What will I lose if I do not get the desired outcome from this decision? What other options do I have?

For more specific climate information for your location refer to Australian Rainman, the latest "Climate Note" at www.dpi.qld.gov.au/climate or contact me through the DPI Call Centre on 13 25 23.

Last updated: 3 March 2003