Seasonal Climate Outlook Message for February to May 2003

The bottom line

Rainfall Probabilities Vary across Queensland (Dated 03/01/03)

The seasonal outlook for February to April varies across Queensland. Currently there is a 50-70% chance of getting above the long term February to April median rainfall in the strip running from the north west of the state to the central west and for small areas along the coast.

Rainfall probabilities across the rest of Queensland though, are lower at around 30-50%. For example, there is a 60% chance of getting above the long term February to April median rainfall of 137mm at Winton. This compares with a 38% chance of getting above the long term February to April median rainfall of 246 mm at Nebo.

While these probabilities do indicate the potential for some relief rain, unfortunately there remains only a relatively low chance of getting those big, widespread, well above average rainfall events needed to break the current drought pattern.

Other areas with a low chance of getting above median rainfall totals for the same period include NSW, Victoria, south east South Australia and south west Western Australia. Probabilties however, are higher for the Northern Territory and the northern half of Western Australia and South Australia.

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

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

When dealing with probability based forecasts it is important to consider the additional information provided. For example, based on the recent pattern of the SOI there is a 70% chance of getting above 130mm at Dalby on the eastern Darling Downs for February to April. Therefore there is a 30% chance of not getting 130mm.

Another way of looking at this is that in 7 years out of 10 (or just under three quarters of years) with the current SOI pattern, Dalby has received more than 130mm in February to April. Therefore in 3 years out of 10 (or just over one quarter of years) with the current SOI pattern, less than 130mm has been recorded at Dalby for February to April.

The monthly SOI value rose from minus 13.2 for December to minus 2.0 for January. Based on the shift in value the SOI is in a "Rapidly Rising" phase. For those who like to follow the fluctuations of the SOI, daily updated values are available on (07) 46881439.

Other years that have had the same SOI phase in January include 2002, 1996, 86, 82, 80, 77, 68, 67, 63, 54, 53, 40, 37, 35, 31, 30, 20, 1902, and 1901. Many people find it useful to compare rainfall patterns and farming conditions for February to April in their area for those years.

Given the existing widespread drought conditions much interest is being shown in the next passage of the intra-seasonal oscillation (or MJO). 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 be remembered that 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 the Christmas/new year period triggering some widespread but patchy storm activity. It is next due in mid February.

Unfortunately the El Nino sea temperature pattern can still be found in the Pacific. It is likely that this El Nino will linger through to mid/late autumn. A key time in the near future to get an indication as to the likely breakdown of this pattern will occur shortly after the next MJO.

While the MJO is normally associated with helping to initiate rainfall events it can also trigger strong westerly wind bursts (rather than the "normal" south east trade winds) across the central Pacific. At this time of year, westerly wind bursts in the Pacific can be an early indicator as to a developing (or ongoing) El Nino event.

Any changes that occur in ocean and atmospheric patterns for the next few months are crucial as autumn is the usual transition period for El Nino events.

It's worth pointing out that this is not a prediction of when the drought is going to break. That may take several months of continual above average falls in many regions and as most readers would be aware, unfortunately the breakdown of major drought events often does not occur evenly across all affected areas.

We will monitor this situation and make available information as soon as there has been some measurable breakdown of the El Nino. An interesting site in terms of ongoing El Nino developments is the US Climate Prediction Centre at www.cpc.ncep.noaa.gov/ http://www.cpc.ncep.noaa.gov/>

Previous El Nino periods 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. When did conditions improve in your area following these events?

El Nino events have an impact on a global scale. Drier than average conditions for the next three months are expected over much of Indonesia, Micronesia, south east Africa, north east Brazil and northern South America.

As well, for the remainder of the northern winter drier than average conditions are expected in parts of the USA and Canada, especially across the Ohio and Tennessee Valleys, the eastern Great Lakes and the northern U.S. Rockies.

Wetter than average conditions though are expected along most of the southern tier of the USA, coastal sections of Ecuador and northern Peru during February to April 2003.

As part of the QCCA drought program, the probabilities of significant re-charge events for ground water aquifers in Queensland have been calculated. For the Burnett, Lockyer and Stanthorpe aquifer and catchments the probability of getting significant recharge rainfall events remains low at around 10%. The chance is slightly higher for the Bowen catchment at around 20%.

The number of Queensland shires drought declared under state drought processes continues to increase. As of the 30th January there were 80 shires and 2 part shires declared. There are also approximately 650 Individually Drought Declared Properties (IDP) in an additional 25 shires.

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

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/ 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: 2 February 2003