Extreme rainfall events are likely to become more extreme. This means more rain, more flooding.

ADVICE: Climate change will prompt people to find new ways of doing things and new ways for people to contribute.

We are in the unique position of knowing what our choices are and I want people to be informed to make decisions based on good science. I do think it's important that we try to understand how much climate change is likely to affect New Zealand in the years ahead.

Then, once you understand that significant change is coming, and some of it is now inevitable, planning how we will adapt and thrive in a changing climate becomes a priority.

Parts of New Zealand will also become more prone to drought.

Adapting and thriving in a changing climate is the focus of Niwa's Fieldays display at Mystery Creek. Using highly detailed computer graphics, farmers will be able to find out what climate change might look like on their farm, and explore the choices they face.

READ MORE: Ice, fire, storms and heat: Climate change is now part of our everyday lives

These are the most pressing questions about climate change for farmers.

Niwa chief climate scientist Dr Sam Dean.

What sort of changes to the climate can farmers expect in the next 100 years?

This depends on what happens globally to reduce greenhouse emissions. However, the mean annual temperature will increase across New Zealand even if global emissions stabilise. Temperature changes will vary from region to region, but if global emissions continue to grow unabated, temperatures across the country are expected to rise on average by 3C by 2090.

There will also be fewer frosts with the largest decreases in higher elevations, and more hot days where the temperature will be greater than 25C. The biggest increases in hot days will be in northern and eastern areas.

Rainfall patterns will also change. There will be more rain in the west and south of New Zealand and less in the east and north, reflecting strengthening westerly winds. Extreme rainfall events are likely to become more extreme. This means more rain, more flooding and stronger, more damaging winds.

Conversely, parts of New Zealand will also become more prone to drought.

What will this mean to farming practices?

Changes in temperature will affect a range of farm activities. Crops that require warm climates may be able to be grown in areas currently considered too cool. Harvest times may be earlier and pasture production may increase in southern areas due to an extended growing season. Fewer frosts could mean more productive crops, and those crops may expand to areas currently frost-prone. Some pathogens may become established or harder to control in a changed climate.

More hot days may mean heat stress for stock while decreases in rainfall in the east and north will affect groundwater recharge, irrigation and pasture growth. And while drought will put strain on water resources, larger extreme rainfall events can lead to flooding, slips and damage to infrastructure.

Transportation of goods to processing and onwards to markets here an overseas may become more disrupted.

Is there any likelihood these changes won't happen?

Even if emissions were to stop completely today the impacts of "locked in" climate change will continue to be felt for decades to come. But the severity of any changes we may see is still very much dependent on the world's collective actions to reduce emissions. The international Paris agreement aims to hold the increase in the global average temperature to well below 2 °C above pre-industrial levels, but current commitment levels are unlikely to be enough to achieve that goal.

How is Niwa helping farmers and rural communities be better prepared for climate change?

Niwa focuses on providing information on climate change impacts at a local scale for future planning in the primary sector. But we also offer services that are designed to help farmers and growers make confident and informed operational decisions, such as when and where to irrigate, fertilise, spray, harvest and move stock. We believe that optimising current farming practices is one of the most effective adaptation strategies.

If you have one piece of advice for farmers about coping with climate change, what would it be?

Farmers are known for their resilience and ability to adapt to changing conditions. But, climate change will almost certainly go well beyond previous experience so sound scientific advice will be invaluable.

I'm a great believer in the power of humankind and our ability to innovate and work our way through issues.