Adapting to a changing climate

Farmers are used to dealing with the weather. However, extreme events like floods and drought are becoming more common, regularly disrupting farming communities, affecting farmers' livelihoods and daily farm management. The severity, scale, and frequency of these weather events will only increase over time. Alongside this, average temperatures will continue to rise, impacting pasture production and animal health among other things.

Understanding how your farm might be affected by climate change and having an adverse event checklist or plan will help strengthen the resilience of your farm system. In addition, this information can help you respond to requests from banks and insurance companies who are starting to look at how climate change risk and resilience could affect farm businesses.

What is predicted to change?

New Zealand has already experienced around 1.1°C warming since the start of the 20th century. By 2040, there will likely be more extended dry spells, longer summers, and shorter winters, and an ongoing increase in storms, wind and rainfall across large parts of the country.

The information below shows NIWA projections for temperature and sea level rise out to 2040. For temperature, the data assumes that global greenhouse gas emissions are stabilised by 2100. This assumes mean annual temperature increases of between 0.7-0.9 °C by 2031-2050.

On-farm adaptation

When considering farm system changes or significant investments such as infrastructure, it is crucial to take a long-term perspective and think about the need to adapt to a changing climate. The following questions might help:

Pasture health and productivity

• How will changes in rainfall timing impact my pastures/crops?
• Can I still manage my water supply to meet pasture needs?
• Are there any new or existing plant diseases that could affect pasture/crops?
• Would I be able to supply additional irrigation in a significantly reduced rainfall scenario?
• Do I have the optimal variety of pasture/crops, considering their tolerance limits?
• What pests should I be looking out for?
• What does an increase in saltwater concentration affect my pasture/crop?
• What other grass species, crops, or trees could work on my farm?

Stock health

• Is there a risk of heat stress for my animals (consider factors like water access, walking distance, shelter and water supply)?
• Are there areas that could be developed to provide shade and shelter for stock and/or windbreaks?
• Are there vulnerable areas where extreme events, like floods, could impact my stock?
• What areas on my property are prone to waterlogging?
• What are the indicators of drought on my property, and what is my response plan?
• When do I initiate it?

Property Infrastructure

• Which property infrastructure could be damaged by storm events, flooding, or sea level rise? (e.g. fences, races, buildings, irrigation units)
• Are there any viable options to enhance the resilience of the property to extreme events?
• Is there any infrastructure that requires moving to avoid flood or sea level rise?
• Where are the “safe” areas on my property for critical infrastructure?

Water Management

• How can I achieve improved water efficiency in:
  • Infrastructure – improve the efficiency of irrigation (e.g. lower application intensity, less noise or a travelling drip to reduce wind inefficacy.
  • Crops – what effect will crop management practices have on water stress?
  • Soil – how can I increase the amount of water in my soil cab store to add resilience
• Can I access additional water through existing methods or shared consents with neighbours in my catchment?
• Are there any water storage options available?
• How can I manage the deficit between water availability and water demand on my farm?
• Will seal level rise or increased freshwater extraction affect the salt content of my water supply?
• Assess the effectiveness of my drainage network. What actions can be taken to manage intense rainfall events?
• How good is my existing drainage network? What actions can be taken to manage intense rainfall events?
• Are there any flood-prone areas where a waterway could change course?

What is DairyNZ doing?

DairyNZ is actively advocating for farmers as the Government develops and implements adaptation policies to address New Zealand’s response to climate change.

We also have a range of research projects underway looking at different aspects of adaptation, including:

• World-leading animal genetic gain, incorporating resilience traits into Breeding Worth.
• Developing data-driven tools to better understand and manage heat stress in dairy cows.
• Advancing forage frontiers, looking at the speed of change and likely impacts on the forage base and likelihood of thermal stress and drought.
• Driving regional adaptation.

We also partner with other research organisations on this work and others, for example the Deep South National Science Challenge:

• Fieldwork Factsheet: Dairy farming with floods, droughts and a changing climate
• Dairy NZ: Matamata-Piako Climate Resilience & Adaptations
• Journal: Summer growth rates and annual yields of perennial ryegrass in the Upper North Island expected to decline as a result of climate change
• Journal: Understanding dairy farmers' perceptions of climate change and adaptation decisions in the lower South Island of New Zealand
• Journal: Dairy farming exposure and impacts from coastal flooding and sea level rise