Papers on rainfall, flooding and droughts in Australia
Posted by Ari Jokimäki on January 12, 2011
The flooding in Australia has been in the news in last few days. The fellow Australian bloggers have also wrote about the event:
- The Queensland floods – Skeptical Science
- Australia’s “Katrina”: this is what I feared…Queensland drowning, dozens missing feared dead – Watching the Deniers
- Brisbane is going under: city centre evacuated, thousands of properties at risk – Watching the Deniers
- Scenes from a disaster: Brisbane, January 2011 – Watching the Deniers
- Even the gods were afraid: a flood of truly “Biblical” proportions – Watching the Deniers
- Queensland floods are “consistent with climate change predictions” – Watching the Deniers
- Queensland catastrophe: looting in Ipswich; evacuation centres overwhelmed; thousands without power; fears of disease; 30,000 people to be effected in Brisbane; a “gruesome day” is predicted; whole families missing – Watching the Deniers
- HUN War on Science: Andrew Bolt, lying about Queensland floods – Watching the Deniers
- Brisbane is going under (part 2): how the city may flood; if you can, please give – Watching the Deniers
John Cook of Skeptical Science lives in Brisbane which is being flooded currently. The Latest report from John says:
I’m happy to say the Cook family is safe and dry – we happen to be located in a relatively elevated area (not by design – extreme flooding was not even on my radar when we moved into the area).
I hope that situation remains that way – that John and his family stay safe.
Papers on rainfall, flooding and droughts in Australia
This is a list of papers on flooding and droughts in Australia. The list is not complete, and will most likely be updated in the future in order to make it more thorough and more representative.
Assessing trends in observed and modelled climate extremes over Australia in relation to future projections – Alexander & Arblaster (2009) “Multiple simulations from nine globally coupled climate models were assessed for their ability to reproduce observed trends in a set of indices representing temperature and precipitation extremes over Australia. Observed trends over the period 1957–1999 were compared with individual and multi-modelled trends calculated over the same period. When averaged across Australia, the magnitude of trends and interannual variability of temperature extremes were well simulated by most models, particularly for the index for warm nights. The majority of models also reproduced the correct sign of trend for precipitation extremes although there was much more variation between the individual model runs. A bootstrapping technique was used to calculate uncertainty estimates and also to verify that most model runs produce plausible trends when averaged over Australia. Although very few showed significant skill at reproducing the observed spatial pattern of trends, a pattern correlation measure showed that spatial noise could not be ruled out as dominating these patterns. Two of the models with output from different forcings showed that the observed trends over Australia for one of the temperature indices was consistent with an anthropogenic response, but was inconsistent with natural-only forcings. Future projected changes in extremes using three emissions scenarios were also analysed. Australia shows a shift towards warming of temperature extremes, particularly a significant increase in the number of warm nights and heat waves with much longer dry spells interspersed with periods of increased extreme precipitation, irrespective of the scenario used.” Lisa V. Alexander and Julie M. Arblaster, International Journal of Climatology, Special Issue: Climate Extremes: progress and future directions, Volume 29, Issue 3, pages 417–435, 15 March 2009, DOI: 10.1002/joc.1730. [full text]
Association between Australian rainfall and the Southern Annular Mode – Meneghini et al. (2007) “In this study, we explore the relationships between seasonal Australian rainfall and the Southern Annular Mode (SAM). We produce two seasonal indices of the SAM: the Antarctic Oscillation Index (AOI), and an Australian regional version (AOIR) using ERA-40 mean sea-level pressure (MSLP) reanalysis data. The seasonal rainfall data are based on gridded monthly rainfall provided by the Australian Bureau of Meteorology. For the period 1958–2002 a significant inverse relationship is found between the SAM and rainfall in southern Australia, while a significant in-phase relationship is found between the SAM and rainfall in northern Australia. Furthermore, widespread significant inverse relationships in southern Australia are only observed in winter, and only with the AOIR. The AOIR accounts for more of the winter rainfall variability in southwest Western Australia, southern South Australia, western and southern Victoria, and western Tasmania than the Southern Oscillation Index. Overall, our results suggest that changes in the SAM may be partly responsible for the current decline in winter rainfall in southern South Australia, Victoria, and Tasmania, but not the long-term decline in southwest Western Australian winter rainfall.” Belinda Meneghini, Ian Simmonds, Ian N. Smith, International Journal of Climatology, Volume 27, Issue 1, pages 109–121, January 2007, DOI: 10.1002/joc.1370. [full text]
An assessment of recent trends in Australian rainfall – Smith (2004) “Trends in Australian rainfall over the period 1901 to 2002 are analysed with the aim of evaluating and assessing long-term trends. In particular, this study examines long-term trends in Australian rainfall with the aim of identifying any continental-scale patterns that could be described as `unusual’. All-Australia annual average rainfall and all-Australia average decile time series indicate a positive long-term trend over the full period. Trend maps indicate that much of this trend is the result of increases in summer half-year rainfall over western, northern and central Australia that have occurred over the latter part of the record 1952-2002. While significant negative trends in winter half-year rainfall over southwest Western Australia are evident, there is little evidence that they are part of any continental-scale trends, at least not on 100 or 50-year time-scales. Empirical Orthogonal Teleconnection patterns (EOTs) of annual rainfall provide a means for delineating independent spatial modes. These indicate that much of the variance in all-Australian rainfall can be attributed to the first two modes that cover much of central eastern Australia and central western Australia. In addition, the pattern of positive trends comprises at least two modes, which, being linearly independent, indicate that the large-scale pattern of increases is itself unusual in a historical context.” Smith, I., Australian Meteorological Magazine, Vol. 53, no. 3, pp. 163-173. Sep 2004. [full text]
Climate change and Australia: Trends, projections and impacts – Hughes (2003) “This review summarizes recent research in Australia on: (i) climate and geophysical trends over the last few decades; (ii) projections for climate change in the 21st century; (iii) predicted impacts from modelling studies on particular ecosystems and native species; and (iv) ecological effects that have apparently occurred as a response to recent warming. Consistent with global trends, Australia has warmed ∼0.8°C over the last century with minimum temperatures warming faster than maxima. There have been significant regional trends in rainfall with the northern, eastern and southern parts of the continent receiving greater rainfall and the western region receiving less. Higher rainfall has been associated with an increase in the number of rain days and heavy rainfall events. Sea surface temperatures on the Great Barrier Reef have increased and are associated with an increase in the frequency and severity of coral bleaching and mortality. Sea level rises in Australia have been regionally variable, and considerably less than the global average. Snow cover and duration have declined significantly at some sites in the Snowy Mountains. CSIRO projections for future climatic changes indicate increases in annual average temperatures of 0.4-2.0°C by 2030 (relative to 1990) and 1.0-6.0°C by 2070. Considerable uncertainty remains as to future changes in rainfall, El Nino Southern Oscillation events and tropical cyclone activity. Overall increases in potential evaporation over much of the continent are predicted as well as continued reductions in the extent and duration of snow cover. Future changes in temperature and rainfall are predicted to have significant impacts on most vegetation types that have been modelled to date, although the interactive effect of continuing increases in atmospheric CO2 has not been incorporated into most modelling studies. Elevated CO2 will most likely mitigate some of the impacts of climate change by reducing water stress. Future impacts on particular ecosystems include increased forest growth, alterations in competitive regimes between C3 and C4 grasses, increasing encroachment of woody shrubs into arid and semiarid rangelands, continued incursion of mangrove communities into freshwater wetlands, increasing frequency of coral bleaching, and establishment of woody species at increasingly higher elevations in the alpine zone. Modelling of potential impacts on specific Australian taxa using bioclimatic analysis programs such as BIOCLIM consistently predicts contraction and/or fragmentation of species’ current ranges. The bioclimates of some species of plants and vertebrates are predicted to disappear entirely with as little as 0.5-1.0°C of warming. Australia lacks the long-term datasets and tradition of phenological monitoring that have allowed the detection of climate-change-related trends in the Northern Hemisphere. Long-term changes in Australian vegetation can be mostly attributed to alterations in fire regimes, clearing and grazing, but some trends, such as encroachment of rainforest into eucalypt woodlands, and establishment of trees in subalpine meadows probably have a climatic component. Shifts in species distributions toward the south (bats, birds), upward in elevation (alpine mammals) or along changing rainfall contours (birds, semiarid reptiles), have recently been documented and offer circumstantial evidence that temperature and rainfall trends are already affecting geographic ranges. Future research directions suggested include giving more emphasis to the study of climatic impacts and understanding the factors that control species distributions, incorporating the effects of elevated CO2 into climatic modelling for vegetation and selecting suitable species as indicators of climate-induced change.” Lesley Hughes, Austral Ecology, Volume 28, Issue 4, pages 423–443, August 2003, DOI: 10.1111/j.1442-9993.2003.tb00266.x. [full text]
Trends in extreme rainfall indices for an updated high quality data set for Australia, 1910–1998 – Haylock & Nicholls (2000) “Daily rainfall was analysed at 91 high quality stations over eastern and southwestern Australia to determine if extreme rainfall had changed between 1910 and 1998. Three indices of extreme rainfall were examined: the number of events above an extreme threshold (extreme frequency); the average intensity of rainfall from extreme events (extreme intensity); and the proportion of total rainfall from extreme events (extreme percent). Several problems are discussed associated with designing such indices under a climate with significant trends in the number of raindays. Three different methods are used for calculating the extreme intensity and extreme percent indices to account for such trends in raindays. A separate analysis was carried out for four separate regions with significant results including a decrease in the extreme frequency and extreme intensity in southwest Western Australia and an increase in the extreme percent in eastern Australia. Trends in the extreme intensity and extreme percent are largely dependent on the method used to calculate the index. Total rainfall is strongly correlated with the extreme frequency and extreme intensity indices, suggesting that extreme events are more frequent and intense during years with high rainfall. Due to an increase in the number of raindays during such years, the proportional contribution from extreme events to the total rainfall depends on the method used to calculate this index.” Malcolm Haylock, Neville Nicholls, International Journal of Climatology, Volume 20, Issue 13, pages 1533–1541, 15 November 2000, DOI: 10.1002/1097-0088(20001115)20:133.0.CO;2-J. [full text]
Waterfalls, floods and climate change: evidence from tropical Australia – Nott & Price (1999) “Sediments preserved at the base of rare types of waterfalls provide records of terrestrial floods to 30 kyr or more, being approximately 6–10 times longer than that usually obtained from the traditional slackwater method. These coarse-grained sand deposits form ridges and levees adjacent to plunge pools at the foot of unindented escarpments and within gorge overflow bedrock channel systems. The extension of palaeoflood records into the Late Pleistocene allows comparisons to be made between periods of extreme floods and dramatically different climatic regimes. Our results highlight that the last 30 kyr were dominated by alternating periods of extreme and relatively low magnitude floods that correspond to particular climatic regimes. Recent predictions from Global Climate Models suggest that tropical regions will experience dramatic increases in the frequency and magnitude of extreme floods under a future altered climate. Plunge-pool palaeoflood records can be used to at least partially test such predictions by determining whether similar previous climate/flood associations have occurred within a region.” Jonathan Nott and David Price, 1999, Earth and Planetary Science Letters, Volume 171, Issue 2, 30 August 1999, Pages 267-276, doi:10.1016/S0012-821X(99)00152-1.
Australian rainfall changes, 1910-1995 – Hennessy et al. (1999) “Annual and seasonal trends in heavy daily rainfall, total rainfall and the number of rain days were calculated for the whole of Australia and each State/Territory from 1910 to 1995, using high-quality daily data from 379 stations. Trend significance was determined using the Kendall-tau test and trend magnitudes were computed from linear regression. While many statistically significant trends were found, non-significant trends judged to be of special interest are noted. From 1910-1995, annual total rainfall has undergone secular changes with a significant 14 per cent increase in Victoria and non-significant increases of 15-18 per cent in New South Wales (NSW), the Northern Territory (NT) and South Australia (SA). When analysed seasonally, non-significant changes of 10-40 per cent were found in some States. Heavy rainfall indices were defined as the 99th and 95th percentiles (the highest and 5th highest daily amounts, respectively, in each three-month season). Australian areal-mean heavy rainfall has not changed significantly in any season. However, on a regional basis significant increases in heavy rainfall emerged in SA in summer and NSW in autumn, while significant decreases occurred in southwest Western Australia (SWWA) in winter. Important non-significant increases of 10-45 per cent were also found in some States. There has been a significant 10 per cent rise in the annual Australian-average number of rain days. Significant increases of almost 20 per cent were found in the NT and NSW despite a significant 10 per cent decline in SWWA. Regionally, significant increases of 20-50 per cent have occurred in some States, with large changes in the frequency of light rainfall. Strong correlations exist between interannual variations in temperature, total rainfall, heavy rainfall and the number of rain days. Increases in Australian rainfall since 1910 are generally linked to an increase in heavy rainfall and the number of rain days. ENSO variability is partly responsible, as is enhanced monsoon activity in the 1970s and changes in other large-scale circulation features. Decreased rainfall in southwest WA is also linked to circulation changes.” Hennessy, KJ | Suppiah, R | Page, CM, Australian Meteorological Magazine, Vol. 48, no. 1, pp. 1-13. Mar 1999. [full text]
Annual climate summary 1998: Australia’s warmest year on record – Collins & Della-Marta (1999) “A high quality dataset developed to monitor long-term temperature trends in Australia has been updated. The annual mean time-series indicates that in 1998 Australia recorded its highest ever annual mean temperature since the start of the high-quality record in 1910. The largest contribution to the record temperature came from much higher than usual minimum temperatures throughout the northern half of the continent. High-quality rainfall and cloud cover datasets have also been updated. Greater than average cloud cover during 1998 contributed to milder overnight temperatures and generally wetter than average conditions through most of the country. The result of a warm, wet and cloudy year during 1998 is unusual in the instrumental record for Australia as studies in interannual climate variations indicate that mean temperature is generally out of phase with both rainfall and cloud cover. However, these apparent inconsistencies support the suggestion made by previous studies that the relationship between Australian temperature and rainfall changed abruptly during the early 1970s.” Collins D. A. & Della-Marta P. M., 1999, Aust. Meteorol. Mag. 48, 273–83. [full text]
Trends in total rainfall, heavy rain events and number of dry days in Australia, 1910–1990 – Suppiah & Hennessy (1998) “Trends in heavy rainfall, total rainfall and number of dry days in Australia have been analysed using daily rainfall records at 125 stations. Summer and winter halves of the year were considered separately for the period 1910–1990. The summer half-year is defined as November–April, while the winter-half is May–October. Heavy rainfall is defined as the 90th and 95th percentiles of daily rainfall in each half-year. The magnitude of trends was derived from linear regression while statistical significance was determined by Kendall-Tau and field significance tests. Increasing trends in heavy rainfall and total rainfall have occurred during the summer half-year, but only 10–20% of stations have statistically significant trends. During the winter half-year, heavy rainfall and total rainfall have also increased, except in far southwest Western Australia and inland Queensland. There has been a reduction in the number of dry days in both halves of the year, except in far southwest Western Australia and at a few stations in eastern Australia where there has been an increase in the number of dry days in the winter half-year. Changes in the number of dry days were statistically significant at over 50% of stations. Hence there are regions showing coherent increases and decreases in rainfall which may be due to systematic changes in climate during the last century. Trends were averaged over three broad regions with adequate station coverage. There has been a general decrease in dry days with an increase in total and heavy rainfall intensity in the northeast and southeast, and a decrease in total and heavy rainfall in the southwest. These rainfall changes are related to changes in other climate variables such as temperature and cloud cover in Australia.” Ramasamy Suppiah, Kevin J. Hennessy, International Journal of Climatology, Volume 18, Issue 10, pages 1141–1164, August 1998, DOI: 10.1002/(SICI)1097-0088(199808)18:103.0.CO;2-P.
An extended high-quality historical rainfall dataset for Australia – Lavery et al. (1997) “Lavery et al. (1992) identified 191 high-quality long-term rainfall records after an exhaustive search of documentation on Australian rainfall sites, coupled with statistical tests. This dataset had a relatively poor spatial distribution and so high-quality composited rainfall records and some records of shorter duration now have been added. The final dataset of 379 high-quality rainfall records (341 of which commence no later than 1910) can reliably monitor rainfall trends for most of Australia. The techniques used to composite the records, and the resulting dataset, are described. With this enhanced spatial coverage it is feasible to perform an areal averaging of precipitation for Australia. A time-series of all-Australian annual rainfall since 1890 has been constructed. Time-series were also constructed of northern summer and southern winter Australian rainfall. In all time-series the El Niño/Southern Oscillation signal is clearly evident.” Lavery, B., Joung, G. and Nicholls, N., 1997, Aust. Meteorol. Mag. 46, 27–38. [full text]
Implications of climate change due to the enhanced greenhouse effect on floods and droughts in Australia – Whetton et al. (1993) “Potential impacts of climate change on heavy rainfall events and flooding in the Australian region are explored using the results of a general circulation model (GCM) run in an equilibrium enhanced greenhouse experiment. In the doubled CO2 simulation, the model simulates an increase in the frequency of high-rainfall events and a decrease in the frequency of low-rainfall events. This result applies over most of Australia, is statistically more significant than simulated changes in total rainfall, and is supported by theoretical considerations. We show that this result implies decreased return periods for heavy rainfall events. The further implication is that flooding could increase, although we discuss here the many difficulties associated with assessing in quantitative terms the significance of the modelling results for the real world. The second part of the paper assesses the implications of climate change for drought occurrence in Australia. This is undertaken using an off-line soil water balance model driven by observed time series of rainfall and potential evaporation to determine the sensitivity of the soil water regime to changes in rainfall and temperature, and hence potential evaporation. Potential impacts are assessed at nine sites, representing a range of climate regimes and possible climate futures, by linking this sensitivity analysis with scenarios of regional climate change, derived from analysis of enhanced greenhouse experiment results from five GCMs. Results indicate that significant drying may be limited to the south of Australia. However, because the direction of change in terms of the soil water regime is uncertain at all sites and for all seasons, there is no basis for statements about how drought potential may change.” P. H. Whetton, A. M. Fowler, M. R. Haylock and A. B. Pittock, 1993, Climatic Change, Volume 25, Numbers 3-4, 289-317, DOI: 10.1007/BF01098378.
Australian rainfall trends during the twentieth century – Nicholls & Lavery (1992) “A set of high-quality rainfall records is used to examine rainfall trends over Australia during the twentieth century. The 191 stations used have been selected by an exhaustive search of documentation regarding instrumentation, observational practices, site relocations, and exposure. Statistical tests of the reliability of observing practices also have been applied in the selection process, as well as tests to detect inhomogeneities. The data set used is the most reliable available for monitoring rainfall trends during the twentieth century. The data have been clustered objectively into groups exhibiting similar variations in annual rainfall. A subset of 10 stations (one for each cluster) suitable for long-term monitoring of rainfall trends is selected. The trends in annual, winter, and summer rainfall are exhibited. The study confirms trends noted in earlier studies. Summer rainfall over much of eastern Australia increased abruptly around 1950. In the south-west of the continent most stations recorded a smoother trend to lower winter rainfall, although there is a small area with increased rainfall. The identification of these trends in this study indicates that they are not the result of unreliable observations or to doubtful compositing of stations into groups. These trends have now continued for some decades after their initial observation. It is possible, however, that the twentieth century trends simply reflect a return to conditions of the late nineteenth century, rather than a trend that could be unambiguously attributed to an enhanced ‘greenhouse effect’.” Neville Nicholls, Beth Lavery, International Journal of Climatology, Volume 12, Issue 2, pages 153–163, March 1992, DOI: 10.1002/joc.3370120204.
A historical rainfall data set for Australia – Lavery et al. (1992) “An exhaustive search of documentation regarding observational practices, instrumentation, site relocations and exposure of instruments has been conducted for Australian rainfall stations. The aim has been to identify high quality long-term rainfall stations which could be used to monitor and assess climate changes. Statistical tests were also employed in the selection process to determine the reliability of observing practices and to check for inhomogeneities in the data. The data set is the most reliable available for monitoring rainfall trends in Australia during the twentieth century. These data will be utilised in further studies as references for testing the reliability of records from neighbouring stations, and in the process of modifying such records. They can confidently be used in climate studies requiring data without spurious trends or inhomogeneities.” Lavery, B., Kariko, A. and Nicholls, N., 1992, Aust. Meteorol. Mag. 40, 33–39. [full text]
Analysis of Australian rainfall data with respect to climate variability and change – Srikanthan & Stewart (1991) “Predictions by general circulation models of changes in rainfall rates over Australia under the double carbon dioxide scenario are conflicting. As it will be some time before the quality of these predictions improves, our best indicator of rainfall variability and change is the analysis of the behaviour of recorded data over time. This paper presents the results of statistical analysis of annual and monthly rainfall data for 69 rainfall stations around Australia. The annual and monthly time-series are analysed for trend and jump in the mean. Graphical plots of the rainfall data indicate low frequency variations but there is no significant or conclusive evidence of climate change impacts within the analysed annual rainfall records. However, the data from a third of the stations indicate a change in winter rainfall, with the change points being late in the last century or early in the present century.” Srikanthan, R. & Stewart, B. J., 1991, Aust. Meteorol. Mag. 39, 11–20. [full text]
Recent climatic change in Australia: Implications for a CO2-warmed earth – Pittock (1983) “A significant change in mean precipitation occurred over much of Australia between 1913–45 and 1946–78. This is described on a seasonal basis and related to possible changes in the atmospheric circulation. It now appears that during this time mean surface temperatures in the mid southern latitude zone increased by up to 1 °C. This temperature change could be at least partly due to an increase in atmospheric CO2 concentrations from about 260 ppmv in the early nineteenth century. In any case the observed temperature increase is similar to the predicted future effects of a 50% increase in atmospheric CO2 concentrations. Thus the climatic change which occurred earlier this century is at least a good analogy for the effects of a CO2-induced global warming which is expected to occur over a similar time interval in the future. This allows the construction of more detailed and quantitative climate scenarios. The most noteworthy conclusion is that marked changes in the seasonally of precipitation should be anticipated, with seasonal changes in some areas being of the order of 50% or more for a doubling of CO2 content. The results are in general consistent with earlier more qualitative scenarios for Australia.” A. B. Pittock, Climatic Change, Volume 5, Number 4, 321-340, DOI: 10.1007/BF02423529.
On the Detection of Climate Change – Doran & McGilchrist (1983) “In recent times, a body of opinion has developed supporting a conclusion that an abrupt change in the general climatic mechanisms occurred in some regions of Australia during the 1940’s. Such changes if significant, would have extensive repercussions in hydrologic design and analysis. Most practical procedures rely on an assumption of stationarity and in general the existence of significant non-stationarity will increase markedly the uncertainty in design. Because of the lack of conclusive physical evidence in the short term, the detection of climatic change must be carried out using statistical methods. A method which avoids the problems of assuming or deciding on an underlying probability distribution is the distribution-free CUSUM technique. This method has been used in an analysis of long-term annual rainfalls for the continent of Australia. The case for climate change will be considered on the basis of the results from this analysis. Comparisons of these results and those of previous analyses will be presented.” Doran, DG and McGilchrist, CA. On the Detection of Climate Change [online]. In: Hydrology and Water Resources Symposium (15th : 1983 : Hobart, Tas.). Hydrology and Water Resources Symposium 1983: Preprints of Papers. Barton, ACT: Institution of Engineers, Australia, 1983: 113-117. National conference publication (Institution of Engineers, Australia) ; no. 83/13.
Geographic variation in seasonal rainfall in Australia – an analysis of the 80-year period 1895-1974 – Russell (1981) As described by Srikanthan & Stewart (1991): “In examining the variation in summer and winter rainfall from 200 widely spread stations in Australia over the 80-year period (1895-1974), Russell (1981) found significant increases in summer rainfall at 42 stations, mostly in southeastern Australia. Only two stations showed significant decreases. In contrast, only seven stations showed significant increases in winter rainfall and five showed significant decreases.” Russell, J. S., 1981, Journal of the Australian Institute of Agricultural Science, v. 47(2) p. 59-66.
Changes in seasonal and annual rainfall in New South Wales – Cornish (1977) As described by Srikanthan & Stewart (1991): “From the analysis of annual and monthly rainfall totals for 99 stations throughout New South Wales, Cornish (1977) observed an increase in annual and summer rainfall in central New South Wales.” Cornish, P. M., 1977, Search, 8, 38–40.
Climate Change and the Pattern of Variation in Australian rainfall – Pittock (1975) As described by Srikanthan & Stewart (1991): “Pittock (1975, 1983) analysed 66 years (1913 to 1978) of Australian rainfall data and found an abrupt increase in rainfall circa 1945-46 over most of the continent. He attributes this to a change in climate.” Pittock, A. B., 1975, Search, 6, 498–503.
Climate change in Australia since 1880 – Deacon (1953) As described by Srikanthan & Stewart (1991): “This is in agreement with Deacon (1953), who showed that the summer rainfall over much of the southern part of Australia for the period 1911-1950 was considerably greater than that in the previous 30 years.” Deacon, E. L., 1953, Australian Journal of Physics, 6, 209-18.
Secular change in the rainfall regime of SE Australia – Kraus (1953) As described by Srikanthan & Stewart (1991): “Analysis of long-term rainfall series from Victoria and New South Wales (Kraus 1953) showed a decrease of summer rainfall to a minimum about the turn of the century and fifty years of gradual increase since then.” Kraus, E. B., 1954, Q. Jl R. met. Soc., 80, 591-601. (The publication year is either 1953 or 1954 – Srikanthan & Stewart give different years in their text and in their reference list.)