The grapes don't lie - our climate is changing

I'M a farmer, and to me climate change is not a nature documentary. It is the single greatest threat to my farm, family and the viability of my industry.

My family has a proud heritage in the NSW Hunter Valley, growing grapes and making wine consistently for more than 120 years. Throughout this time we have refined our grape varieties, vineyards and methods to suit the local climate, a climate that is changing rapidly.

Grapevines are a fickle crop extremely sensitive to their environment. A downpour or heatwave can devastate our crop at the drop of a hat - that's why we're often referred to as "whinemakers".

This sensitivity can be frustrating, however it is also what makes Australian wines so interesting and diverse grown across a continent of complex soils and various weather systems.

The grave concern is that since I was born in 1991, the annual cycle of growing grapes has been speeding up, moving forward and compressing.

My family's records show us harvesting chardonnay grapes in mid-February in 1995. We are now harvesting our chardonnay in mid-January.

Over the same period, our shiraz grapes have moved from harvest at the beginning of March to the beginning of February.

The shift is not an anomaly to the Hunter Valley, this forward creep has been recorded nationwide and worldwide by grapegrowers.

Plants don't lie. They are simply reacting to a climate that is consistently and aggressively heating up - at our Pokolbin vineyard in 2017 and 2018, the mercury rose above 47 degrees celsius.

This is unprecedented - and unsustainable. The winter that we need to prune the vines is disappearing. The grapes are more and more exposed to heatwaves and the ongoing drought is damaging to their yield and our finances. These new extremes are the reality of climate change.

It is not too late or too expensive to make the changes necessary to maintain our way of life - hell, we've done it at our vineyard - but this is a worldwide problem that needs public support.

The actions of individuals need to be backed up by the actions of government. The environment isn't just something to enjoy on a hike, it's the life blood on which all of us depend.

If we allow unchecked climate change to continue, it won't be melting ice sheets that hit Australians the hardest, it will be a scarcity of food and water - forget about a nice bottle of wine.

Alisdair Tulloch is a farmer and winemaker with Keith Tulloch Wine