What are Statistics?
NIWA generates ‘Statistics’ from Climate Station Observations collected as part of our Climate Station Network. These are monthly (e.g. ‘for January 1974') and annual (e.g. 'for 1974’) averages for a large range of station locations, calculated for a large range of parameters. The following table provides key parameters that are often used.
| Parameter | Variables included | Unit | Code (Internal) |
| Rain | Total Rainfall | mm | 00 |
| Temperature | Mean Air Temperature | Deg C | 02 |
| Mean Daily Maximum Air Temperatures | Deg C | 03 | |
| Mean Daily Minimum Air Temperatures | Deg C | 04 | |
| Sunshine | Total Sunshine Hours | Hrs | 09 |
| Pressure | Mean Sea-level Pressure at 9am | hPa | 30 |
| Wind | Mean Wind Speed | m/s | 33 |
| Evaporation | Total Penman Potential Evapotranspiration | mm | 34 |
| Total Priestley-Taylor Potential Evapotranspiration | mm | 35 | |
| Total Penman Open Water Evapotranspiration | mm | 36 | |
| Degree days | Total Growing Degree Days for 5C | days | 37 |
| Total Growing Degree Days for 10C | days | 38 | |
| Total Cooling Degree Days for 18C | days | 39 | |
| Total Heating Degree Days for 18C | days | 68 | |
| Winter Chill Units | cu | 77 | |
| Winter Chill Hours | cu | 78 |
What can the data be used for?
- Monthly and annual values can be used to look at long term trends of data.
- Monthly data can be used to analyse seasonal cycles and their changes over time.
Where can I get Statistics?
The data can be obtained from NIWA DataHub
Station Statistics Data Format
- Data is provided in separate csv files / tables per variable in two formats:
- Annual and monthly values are provided as time series formatted csv files
- A combined file / table includes annual AND monthly data for one year in one row, and monthly and annual values in columns.
- Naming convention for the files:
- [agentno]_annual_[variable]_.csv
- [agentno]_monthly_[variable]_.csv
- [agentno]_combined_[variable]_.csv
- The data is “packaged” as zip files for each station and parameter, naming convention for the files is [agentno]_[parameter]. zip.
