Bingie Residents Association Rainfall Recording
See after the charts for more detailed analysis and information about this history of rainfall in the Bingie area.
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History of Rainfall Keeping at Bingie up to 2025
The BRA continue to keep a detailed rainfall record (partly for the water quality program, which we manage). Our record goes back for 21 years at the end of 2017 and we can correlate this with the BOM record at Moruya airport (a good correlation) .
Members of the Bingie community have kept daily rainfall record for several decades (partly for the water quality program, which BRA managed and which ceased at the end of 2018). Since 2019 Philip Hughes has prepared annual summaries of rainfall at Bingie based on the compilation and averaging of three rainfall records, from north to south: 1979-2013 by Steve Young, Alcheringa Lane; 1997-2025 by Philip Hughes and Marjorie Sullivan, Bingie Road, and 1997-2025 by Huon Hassall, Kellys Lane. For the timespans they overlap the average rainfall values are within 3% of each other, although the values recorded for individual years in the three sets of records from 1997 vary by up to 11%. Monthly and daily values are more variable, not just between these three sets of records, but between these and those kept by various members of the water quality sampling team and others in the BRA community. The main reason for this is that the intensity and duration of rain from storms that cross the district varies greatly over short distances.
There are very close correlations between monthly and annual rainfall at Bingie and the two BOM weather stations at Moruya Heads and Moruya Airport. Average annual rainfall at Bingie over the last 47 years has been 946 mm and at Moruya Heads 941 mm.
There are very close correlations between monthly and annual rainfall at Bingie and the two BOM weather stations at Moruya Heads and Moruya Airport. Average annual rainfall at Bingie over the last 47 years has been 946 mm and at Moruya Heads 941 mm.
RAINFALL VARIABILITY IN A 47 YEAR RECORD FROM BINGIE
As the rainfall chart shows, over the last 47 years annual rainfall in Bingie has varied greatly year to year. Much of this variability can be explained by the influence of ENSO events (El Niño and La Niña) and the Millennium Drought. Other events which influence our rainfall are the South Annular Mode (SAM), Indian Ocean Dipole (IOD) and Sudden Stratospheric Warming (SSW).
Brief descriptions of these terms, prepared using AI then checked against reputable scientific websites, are presented in here:
Brief descriptions of these terms, prepared using AI then checked against reputable scientific websites, are presented in here:
ENSO (El Niño-Southern Oscillation) is a major natural climate pattern significantly influencing Australia, causing cycles of El Niño (drier, drought-prone) and La Niña (wetter, flood risk), impacting rainfall, temperatures, and extreme weather like droughts and floods across the continent by shifting Pacific Ocean temperatures and winds. It is a key driver of year-to-year variability, affecting rainfall, frost, heatwaves, and even tropical cyclone numbers, with La Niña often bringing more intense rainfall to eastern Australia than does El Niño, which tends to bring dryness.
The Southern Annular Mode (SAM), or Antarctic Oscillation (AAO), describes the north-south movement of the strong westerly wind belt in the Southern Hemisphere, impacting weather and climate in southern Australia and beyond. A positive SAM pulls winds and storms south, often bringing wetter conditions to southern Australia (especially summer/autumn) and drier to the north; a negative SAM pushes them north, increasing frontal activity and rain for southern areas, though impacts vary by season.
The Indian Ocean Dipole (IOD) significantly affects Australia's climate, particularly rainfall, by varying sea surface temperatures in the tropical Indian Ocean, influencing atmospheric circulation and moisture flow, with Positive IOD phases bring drier conditions warmer west, cooler east, less moisture to SE Australia) like during the 2019 bushfires, while Negative IOD phases bring wetter conditions (cooler west, warmer east, more moisture via northwest cloud bands). The IOD interacts with El Niño and is a key factor in extreme weather events across the continent, especially during winter and spring.
A Sudden Stratospheric Warming (SSW) over Antarctica causes the polar vortex to weaken, shifting the westerly winds towards the equator, which generally brings warmer, drier, and clearer conditions to southern and eastern Australia by reducing rainfall and increasing high-pressure systems, often disrupting typical spring wet patterns and exacerbating drought conditions, as seen in 2019 and recently in late 2025, influencing rainfall for months.
The Millennium Drought (roughly 1996–2010) was caused by a rare confluence of natural climate cycles and was intensified by human-induced climate change. The primary drivers included:
The Southern Annular Mode (SAM), or Antarctic Oscillation (AAO), describes the north-south movement of the strong westerly wind belt in the Southern Hemisphere, impacting weather and climate in southern Australia and beyond. A positive SAM pulls winds and storms south, often bringing wetter conditions to southern Australia (especially summer/autumn) and drier to the north; a negative SAM pushes them north, increasing frontal activity and rain for southern areas, though impacts vary by season.
The Indian Ocean Dipole (IOD) significantly affects Australia's climate, particularly rainfall, by varying sea surface temperatures in the tropical Indian Ocean, influencing atmospheric circulation and moisture flow, with Positive IOD phases bring drier conditions warmer west, cooler east, less moisture to SE Australia) like during the 2019 bushfires, while Negative IOD phases bring wetter conditions (cooler west, warmer east, more moisture via northwest cloud bands). The IOD interacts with El Niño and is a key factor in extreme weather events across the continent, especially during winter and spring.
A Sudden Stratospheric Warming (SSW) over Antarctica causes the polar vortex to weaken, shifting the westerly winds towards the equator, which generally brings warmer, drier, and clearer conditions to southern and eastern Australia by reducing rainfall and increasing high-pressure systems, often disrupting typical spring wet patterns and exacerbating drought conditions, as seen in 2019 and recently in late 2025, influencing rainfall for months.
The Millennium Drought (roughly 1996–2010) was caused by a rare confluence of natural climate cycles and was intensified by human-induced climate change. The primary drivers included:
- Subtropical Ridge Intensification: The most significant meteorological cause was the strengthening and southward shift of the Subtropical Ridge (STR). This high-pressure belt blocked rain-bearing cold fronts and low-pressure systems from reaching southern Australia, particularly during the critical cool-season months.
- El Niño-Southern Oscillation (ENSO): Several strong El Niño events (notably in 1997–98, 2002–03, and 2006–07) occurred during this period. El Niño typically weakens the moist trade winds that bring rain to eastern Australia, pushing moisture away from the continent.
- Climate Change (Global Warming): Rising global temperatures exacerbated the drought by increasing evaporation rates. While natural variability started the event, the Bureau of Meteorology concluded that climate change increased its severity and helped set record-high temperatures during the dry spell.
- Indian Ocean Dipole (IOD): A series of "positive" IOD events also contributed by reducing the moisture transported from the Indian Ocean to the Australian interior.
- Southern Annular Mode (SAM): A persistent negative phase of the SAM at times limited the moist easterly air flows into southeastern Australia, further reducing rainfall.
- Positive Feedback Loops: As the land became parched, "rainfall recycling" decreased. Dry soil and lack of vegetation meant less moisture was evaporated back into the atmosphere to form local rain, creating a self-sustaining cycle of dryness.
In Bingie there generally has been a close correlation, with some notable exceptions, between rainfall and ENSO events. From late 1996 to mid-2010, much of southeastern Australia experienced a prolonged period of dry conditions, known as the Millennium Drought. The Bingie record clearly shows the effects of this drought with rainfall being below average in 11 of the 14 years of its duration.
With thanks to Philip for sharing the data and analyses