Data for A History of Open Weather in New Zealand (HOWNZ)

Data for A History of Open Weather in New Zealand (HOWNZ): an open access 1 km resolution monthly 1910-2019 time-series of interpolated temperature and rainfall grids with associated uncertainty

There is data for both:

  • nni: the variable estimate from natural neighbour interpolation
  • unc: the uncertainty of the variable estimate

for four weather variables:

  • rain: total rainfall
  • tavg: mean air temperature
  • tmin: mean daily minimum air temperature
  • tmax: mean daily maximum air temperature

and these variables help form the file names alongside the year and month.

So for example, nni-rain-1910-01.tif contains the natural neighbour interpolated values for total rainfall in January 1910, and unc-tavg-1979-05.tif contains the uncertainty values for mean air temperature in May 1979.

For storage efficiency when archiving the data, all data value were multiplied by 10 so that they could be stored as 16 bit integer files. Therefore, all the data needs to be divided by 10 to restore the actual data values before the data is used for any analysis.

For users outside of New Zealand who are struggling to download the large data files from here, these data files can also be downloaded from Zenodo at

There are also notes on how to source the input data used to create HOWNZ.

Data and Resources

Additional Info

Field Value
Author Thomas R. Etherington & George L. W. Perry & Janet M. Wilmshurst
Maintainer Thomas R. Etherington
Maintainer Email Thomas R. Etherington
Source Created Unknown
Source Modified Unknown
Language English
Source Identifier
Dataset metadata created 13 September 2021, last updated 22 November 2021