‘Drought means different things to different people. They’re highly variable in New Zealand and, regionally speaking, one occurs here nearly every year. What made 2013 stand out was not only the intensity, but also the widespread nature of it,’ says Chris Brandolino, a forecaster at New Zealand’s National Institute of Water and Atmospheric Research. ‘For any modern farmer, that drought was the worst experienced.’
Similar high pressure conditions that led to low rainfall in 2012–2013 during the current dry spell, particularly this January, according to Brandolino. ‘It is possible that we’ll see more of these types of prolonged anomalous periods, particularly for the North Island, as a consequence of climate change,’ he adds. Soils are now very dry across most of the country. Also, many areas, such as Canterbury, have had unusually dry soils for a sustained period of three to four months. Central and local government, as well as private enterprises, are looking into several options for water storage and irrigation schemes. ‘Such schemes do mitigate the impact of droughts, but only until the stored water runs out or is severely depleted. In other words, local authorities are doing their best to administer water supplies,’ says Brandolino.
New Zealand’s farmers depend on irrigation, which uses groundwater and river resources. ‘There are strict rules for water extraction which limit these impacts,’ says Brandolino. A further complication is New Zealand’s reliance on hydroelectric power. The country generates over 50 per cent of its electricity from dams. Water held back for hydroelectric generation is a useful reserve for farmers, but power has to be balanced with agriculture. ‘Farming in NZ is mostly pasture-based and thus is at the mercy, to a large amount, of receiving enough rainfall to sustain pasture growth,’ says Brandolino.
When rainfall is lower than normal, even for as short a period as one month, the soils dry out quite rapidly due to shallowness and limited moisture holding capacity. ‘Without irrigation, grass growth is quickly impacted which obviously will have an effect on stock nutrition and productivity,’ adds Brandolino
‘Farmers have generally learned how to manage drought by way of destocking, clever farming, such as with drought resistant plants and also planning ahead for supplementary feeding,’ says Brandolino.
This story was published in the March 2015 edition of Geographical Magazine
