The word exceptionalism was invented to describe the USA as an economic entity, or at least to describe the way it used to be.
Now the word has morphed to apply to the whim of the weather gods for the 2025 vintage in South Australia.
I have always advocated that every vintage is different and, after 56 of them in South Australia and many elsewhere, never has that been more evident than in 2025.
2025 is the driest, warmest and earliest vintage of my 56-year career. We started harvest on Friday 7 February, picking Dijon clone Pinot Noir (777, 114 and 115) for Xavier [Bizot]’s Daosa sparkling-wine production. That’s two weeks earlier than the previous earliest and four weeks ahead of average. Piccadilly Valley (Mount Lofty) was 42.5% above average heat summation from October 1 to January 31. In the same period, we received just 63% of average rainfall.
There must be one vintage of the 56 that answers at least one of these extremes. It seems improbable to me that 2025 is the outlier for all three parameters – rainfall, temperature and time of harvest – and for two of my vineyards, The Tiers and Foggy Hill. It is as though the weather gods are taunting me, saying ‘we can still surprise you’, even after I have probably completed 90% of the vintages in which I will have been granted the privilege of participating.
South Australia is getting drier and warmer like most of the world, but the weather patterns of the past couple of decades speak of something else at play.
In 2022 I wrote for this site A century of South Australian climate change, based on the 100-year weather data at Parawa on South Australia’s Fleurieu Peninsula, the home of Foggy Hill, Tapanappa’s Pinot Noir vineyard. Resolved into decades across the 100 years, it demonstrated there are extended alternating periods of exceptionally cool and hot vintages.
The cool decades were 1945–1954 and 1995–2004, each more than 7% below the average, while the 15-year hot period of 2005–2019 was 13% above the average.
In the 2022 article, I speculated after the cool 2000 and 2021 vintages, ‘2022 is tracking markedly below the average. Just maybe we are entering another (cool) swing of the cycle as in 1995–2004. That’s my hope.’
Well, 2023 and 2024 turned out to be even cooler than the previous three vintages and the five-year average (2020–2024) is 4.05% below the long-term average. That’s significant and heralded five very high-quality cool vintages from Foggy Hill and The Tiers.
My 2022 speculation was correct: we were in the middle of a sequence of cooler vintages.
Then along came 2025!
After five successive cool vintages, why are we suddenly in the warmest, driest and earliest vintage of my career in 2025? Does 2025 herald the beginning of another sequence of hot vintages?
As I have written elsewhere, the cool sequence was to a large extent the result of a positive SAM (Southern Annular Modulation), indicating that the chain of high- and low-pressure systems arriving from the west were being sucked down into the Great Southern Ocean, closer to Antarctica, bringing cold air up onto Australia’s southern shore.
The Antarctic Vortex – the huge column of spinning air above the South pole, reaching into the stratosphere – was very strong during this period, fuelled by stratospheric moisture from the massive undersea Tongan volcanic explosion in December 2021. The centripetal force of the Antarctic Vortex sucked the weather systems south, creating a positive SAM.
Now in the words of BOM (the Australian Bureau of Meteorology), ‘The Southern Annular Mode (SAM) is in a negative phase. Recent forecasts show negative SAM is more likely to dominate for the remainder of summer, due to the polar vortex taking an unusually long time to recover from the stratospheric warming event in winter 2024. During summer, a negative SAM decreases rainfall over most of south-eastern Australia.’
The weak Antarctic Vortex has let go of the pressure systems and they are now traversing the globe much closer to the Australian continent. This brings hot, dry air off the continent to our coastal vineyard regions.
Will the Vortex strengthen again? Is the 2025 vintage a unicorn vintage in the middle of a cool-vintage period?
These are speculative questions, but my bet is we will resume cooler vintages after 2025, for some time. The Tongan moisture is still up there in the stratosphere.
What then of the 2025 vintage? How will the quality be affected by the warmth, the drought and the earliness?
The first welcome effect is that we have crop, after the miserable yields of the cool era.
The bunches are plump, the berries good-sized, reflecting a warm, dry flowering period at the end of November. They have ripened rapidly in ideal warm ripening temperatures. The heat accumulation has been consistently elevated 2–3 °C above average, day and night. There have been no prolonged heat spikes and the few days over 35 °C have been isolated and followed by a significant cool change. The night-temperature elevation has accelerated ripeness, the vine working 24 hours a day producing the all-important tertiary compounds, sugaring during the day.
I don’t expect the exquisitely delicate and intense flavours of the past five vintages. I do expect the Chardonnay from The Tiers and the Pinot from Foggy Hill will be better expressions than from the other hot outlier vintages of 2016 and 2018.
In 2016 and 2018, both vineyards held their terroir form and the wines produced are definitively representative of those unique terroirs.
I am cautiously optimistic about the quality of the unicorn 2025 vintage, but to be a winemaker you must be optimistic.
See more harvest reports for regions around the world here.
