Bushra et al. (2025) CAMELS-NZ: hydrometeorological time series and landscape attributes for New Zealand

Identification

• Journal: Earth system science data
• Year: 2025
• Date: 2025-11-03
• Authors: Sameen Bushra, Jeniya Shakya, Céline Cattoën, Svenja Fischer, Markus Pahlow
• DOI: 10.5194/essd-17-5745-2025

Research Groups

• Department of Civil and Environmental Engineering, University of Canterbury, Christchurch, New Zealand
• Earth Sciences New Zealand, Christchurch, New Zealand
• Te Pūnaha Matatini, University of Auckland, Auckland, New Zealand
• Hydrology and Environmental Hydraulics, Wageningen University & Research, Wageningen, the Netherlands

Short Summary

This paper introduces CAMELS-NZ, the first large-sample catchment hydrology dataset for New Zealand, providing hourly hydrometeorological time series and comprehensive landscape attributes for 369 catchments from 1972 to 2024. The dataset fills a critical gap in global hydrology by representing a Pacific Island environment with complex hydrological processes, supporting diverse research applications.

Objective

• To develop and present CAMELS-NZ, the first large-sample, high-resolution (hourly) hydrometeorological dataset for 369 catchments in New Zealand.
• To fill a critical gap in global hydrology by representing a Pacific Island environment with complex hydrological processes.
• To support a wide range of hydrological research applications, including model development, climate impact assessments, predictions in ungauged basins, and large-sample comparative studies.
• To enable innovative research into New Zealand’s hydrological systems, particularly the dynamics of fast-rising rivers in steep topography and intense rainfall events, and hydrological processes in volcanic and alpine environments.

Study Configuration

• Spatial Scale: 369 catchments across New Zealand (North and South Islands). Catchment areas range from a few square kilometers up to 6000 square kilometers.
• Temporal Scale: 1972 to 2024 (52 years). Hourly time series data for hydrometeorological variables. More than 65% of streamflow records exceed 40 years in length.

Methodology and Data

• Models used (for data generation/processing):
  • Thin plate smoothing spline interpolation method (for daily precipitation, temperature, and relative humidity).
  • Multiplicative random cascades (MRCs) (for daily-to-hourly disaggregation of rainfall).
  • Modified Priestley–Taylor method (for potential evapotranspiration, with a Priestley–Taylor coefficient (α) of 1.26).
• Data sources:
  • Streamflow: Earth Sciences New Zealand, regional councils, companies, and private operators.
  • Meteorological (Precipitation, Temperature, Relative Humidity): Virtual Climate Station Network (VCSN).
  • Potential Evapotranspiration (PET): Derived from meteorological data using the modified Priestley–Taylor method.
  • Catchment Attributes: Station Information Management System (SIMS), Freshwater Ecosystem of New Zealand (FENZ) geodatabase, Multiscale River Environment Classification (REC) for Water Resources Management, and a questionnaire survey (for anthropogenic influences).

Main Results

• The CAMELS-NZ dataset, the first large-sample catchment hydrology dataset for New Zealand, has been created and made open-access.
• It comprises hourly time series of streamflow (in cubic meters per second), precipitation (in meters), temperature (in Kelvin), relative humidity (in percentage), and potential evapotranspiration (in meters) for 369 catchments.
• The dataset includes comprehensive static catchment attributes quantifying physical characteristics (land cover, soil properties, geology, topography) and human impacts (abstractions, dams, groundwater/snowmelt influences, ephemeral rivers).
• Data records span from 1972 to 2024, with a significant portion of streamflow records exceeding 40 years.
• The dataset captures New Zealand's diverse hydroclimatic landscapes, including volcanic catchments with high infiltration rates, sediment-rich alpine rivers with glacial contributions, and steep, rainfall-driven fast-rising rivers.

Contributions

• Fills a critical gap in global hydrology by providing a large-sample, high-resolution dataset for a Pacific Island environment, which was previously under-represented in the CAMELS initiative.
• Offers high temporal resolution (hourly data) for key hydrometeorological variables, crucial for studying rapid hydrological responses, flash floods, and developing high-resolution hydrological models.
• Integrates long-term (up to 52 years) and diverse data from fragmented sources into a unified, standardized, and open-access resource, enhancing data accessibility and consistency for researchers.
• Enables innovative hydrological research at national and global scales, supporting model development, climate change impact assessments, predictions in ungauged basins, and comparative hydrology studies.

Funding

• University of Canterbury Sustainable Development Goals PhD scholarship (Sameen Bushra)
• University of Canterbury Department of Civil and Natural Resources Engineering PhD scholarship (Jeniya Shakya)
• Ministry of Business, Innovation, and Employment under contract C01X1703 (Céline Cattoën)
• University of Canterbury Library Open Access Fund (for open access publication)

Citation

@article{Bushra2025CAMELSNZ,
  author = {Bushra, Sameen and Shakya, Jeniya and Cattoën, Céline and Fischer, Svenja and Pahlow, Markus},
  title = {CAMELS-NZ: hydrometeorological time series and landscape attributes for New Zealand},
  journal = {Earth system science data},
  year = {2025},
  doi = {10.5194/essd-17-5745-2025},
  url = {https://doi.org/10.5194/essd-17-5745-2025}
}