CAMELS-GB

Overview

CAMELS-GB is the Great Britain hydrological dataset implementation. Great Britain CAMELS dataset covering catchments in England, Scotland, and Wales.

Dataset Information

• Region: Great Britain
• Module: hydrodataset.camels_gb
• Class: CamelsGb

Features

Static Attributes

Static catchment attributes include: - Basin area - Mean precipitation - Topographic characteristics - Land cover information - Soil properties - Climate indices

Dynamic Variables

Timeseries variables available (varies by dataset): - Streamflow - Precipitation - Temperature (min, max, mean) - Potential evapotranspiration - Solar radiation - And more...

Usage

Basic Usage

from hydrodataset.camels_gb import CamelsGb
from hydrodataset import resolve_data_path

# Initialize dataset
data_path = resolve_data_path("camels_gb")
ds = CamelsGb(data_path)

# Get basin IDs
basin_ids = ds.read_object_ids()
print(f"Number of basins: {len(basin_ids)}")

# Check available features
print("Static features:", ds.available_static_features)
print("Dynamic features:", ds.available_dynamic_features)

# Read timeseries data
timeseries = ds.read_ts_xrdataset(
    gage_id_lst=basin_ids[:5],
    t_range=ds.default_t_range,
    var_lst=["streamflow", "precipitation"]
)
print(timeseries)

# Read attribute data
attributes = ds.read_attr_xrdataset(
    gage_id_lst=basin_ids[:5],
    var_lst=["area", "p_mean"]
)
print(attributes)

Reading Specific Variables

# Read with specific time range
ts_data = ds.read_ts_xrdataset(
    gage_id_lst=basin_ids[:10],
    t_range=["1990-01-01", "1995-12-31"],
    var_lst=["streamflow", "precipitation", "temperature_mean"]
)

# Read basin area
areas = ds.read_area(gage_id_lst=basin_ids[:10])

# Read mean precipitation
mean_precip = ds.read_mean_prcp(gage_id_lst=basin_ids[:10])

Data Sources

The dataset supports multiple data sources for certain variables. Check the class documentation for available sources and use tuple notation to specify:

# Request specific data source
ts_data = ds.read_ts_xrdataset(
    gage_id_lst=basin_ids[:5],
    t_range=["1990-01-01", "1995-12-31"],
    var_lst=[
        ("precipitation", "era5land"),  # Specify ERA5-Land source
        "streamflow"  # Use default source
    ]
)

API Reference

hydrodataset.camels_gb.CamelsGb

Bases: HydroDataset

Source code in hydrodataset/camels_gb.py

class CamelsGb(HydroDataset):

    _COL_MAP = {
        "precipitation":  "pcp_mm",
        "pet":            "pet_mm",
        "temperature":    "airtemp_c_mean",
        "discharge_spec": "q_mm_obs",
        "discharge_vol":  "q_cms_obs",
        "peti":           "pet_mm_intercep",
        "humidity":       "rh_",
        "shortwave_rad":  "solrad_wm2",
        "longwave_rad":   "lwdownrad_wm2",
        "windspeed":      "windspeed_mps",
    }
    _ATTR_FILES = [
        "CAMELS_GB_topographic_attributes.csv",
        "CAMELS_GB_climatic_attributes.csv",
        "CAMELS_GB_humaninfluence_attributes.csv",
        "CAMELS_GB_hydrologic_attributes.csv",
        "CAMELS_GB_hydrometry_attributes.csv",
        "CAMELS_GB_landcover_attributes.csv",
        "CAMELS_GB_soil_attributes.csv",
    ]
    _DATA_REL = "CAMELS_GB/camels_gb/camels_gb/data"
    """CAMELS_GB dataset class extending RainfallRunoff.

    This class provides access to the CAMELS_GB dataset, which contains hourly
    hydrological and meteorological data for various watersheds.

    Attributes:
        region: Geographic region identifier
        download: Whether to download data automatically
        ds_description: Dictionary containing dataset file paths
    """

    def __init__(
        self, uri: str, region: Optional[str] = None, download: bool = False
    ) -> None:
        """Initialize CAMELS_GB dataset.

        Args:
            uri: Path to the data directory
            region: Geographic region identifier (optional)
            download: Whether to download data automatically (default: False)
        """
        super().__init__(uri)
        self.region = region
        self.download = download
        if not str(uri).startswith("s3://"):
            self.aqua_fetch = CAMELS_GB(uri)

    def read_object_ids(self) -> np.ndarray:
        uri = str(self.data_source_dir).rstrip("/")
        ts_rel = f"{self._DATA_REL}/timeseries"
        if self._is_cloud():
            fs = self._make_s3fs()
            names = [p.split("/")[-1] for p in fs.ls(f"{uri}/{ts_rel}".removeprefix("s3://"))]
        else:
            names = os.listdir(os.path.join(uri, *ts_rel.split("/")))
        ids = sorted(set(
            n.replace("CAMELS_GB_hydromet_timeseries_", "").split("_")[0]
            for n in names if n.startswith("CAMELS_GB_hydromet_timeseries_")
        ))
        return np.array(ids)

    def cache_attributes_to_zarr(self) -> None:
        import zarr
        fs = self._make_s3fs()
        uri = str(self.data_source_dir).rstrip("/")
        base = f"{uri}/{self._DATA_REL}"
        dfs = []
        for fname in self._ATTR_FILES:
            path = f"{base}/{fname}".removeprefix("s3://")
            try:
                with fs.open(path) as fh:
                    df = pd.read_csv(fh, index_col="gauge_id", dtype={"gauge_id": str})
                df.index = df.index.astype(str)
                dfs.append(df)
            except Exception as e:
                print(f"  WARN {fname}: {e}")
        static = pd.concat(dfs, axis=1)
        static = static.loc[~static.index.duplicated(keep="first")]
        stations = self.read_object_ids().tolist()
        static = static.reindex(stations)
        static.columns = self._clean_feature_names(list(static.columns))
        static = static.rename(columns={"area": "area_km2", "gauge_lat": "lat"})

        zarr_name = self._attributes_cache_filename.replace(".nc", ".zarr")
        out, opts = self._zarr_path_and_opts(zarr_name)
        n = len(stations)
        root = zarr.open_group(out, mode="w", storage_options=opts, zarr_format=2)
        for col in static.columns:
            vals = static[col].values.astype(str) if static[col].dtype == object else static[col].values
            arr = root.create_array(col, shape=(n,), chunks=(n,), dtype=vals.dtype)
            arr[:] = vals
            arr.attrs["_ARRAY_DIMENSIONS"] = ["basin"]
        basin_arr = root.create_array("basin", shape=(n,), chunks=(n,), dtype=str)
        basin_arr[:] = stations
        basin_arr.attrs["_ARRAY_DIMENSIONS"] = ["basin"]
        root.attrs["coordinates"] = "basin"
        self._write_zarr_units(root, "static")
        print(f"Attributes zarr written to: {out}")

    def cache_timeseries_to_zarr(self) -> None:
        import zarr
        from tqdm import tqdm
        fs = self._make_s3fs()
        uri = str(self.data_source_dir).rstrip("/")
        ts_base = f"{uri}/{self._DATA_REL}/timeseries"
        t_start = self.default_t_range[0].replace("-", "")
        t_end = self.default_t_range[1].replace("-", "")

        stations = self.read_object_ids().tolist()
        all_times = pd.date_range(self.default_t_range[0], self.default_t_range[1], freq="D")
        n, nt = len(stations), len(all_times)
        times_ns = all_times.asi8
        all_vars = list(self._COL_MAP.values())

        data: dict[str, np.ndarray] = {vn: np.full((n, nt), np.nan) for vn in all_vars}
        print(f"Reading {n} stations from OSS...")
        for i, stn in enumerate(tqdm(stations, desc="CAMELS_GB zarr")):
            fname = f"CAMELS_GB_hydromet_timeseries_{stn}_{t_start}-{t_end}.csv"
            path = f"{ts_base}/{fname}".removeprefix("s3://")
            try:
                with fs.open(path) as fh:
                    df = pd.read_csv(fh, index_col="date", parse_dates=True)
                df = df.reindex(all_times)
                for raw_col, zarr_vn in self._COL_MAP.items():
                    if raw_col in df.columns:
                        data[zarr_vn][i] = df[raw_col].values.astype(float)
            except Exception as e:
                print(f"  WARN {stn}: {e}")

        zarr_name = self._timeseries_cache_filename.replace(".nc", ".zarr")
        out, opts = self._zarr_path_and_opts(zarr_name)
        root = zarr.open_group(out, mode="w", storage_options=opts, zarr_format=2)
        for vn in all_vars:
            arr = root.create_array(vn, shape=(n, nt), chunks=(min(n, 100), min(nt, 365)), dtype="float64")
            arr[:] = data[vn]
            arr.attrs["_ARRAY_DIMENSIONS"] = ["basin", "time"]

        time_arr = root.create_array("time", shape=(nt,), chunks=(min(nt, 365),), dtype="int64")
        time_arr[:] = times_ns
        time_arr.attrs["_ARRAY_DIMENSIONS"] = ["time"]
        time_arr.attrs["units"] = "nanoseconds since 1970-01-01"
        time_arr.attrs["calendar"] = "proleptic_gregorian"

        basin_arr = root.create_array("basin", shape=(n,), chunks=(n,), dtype=str)
        basin_arr[:] = stations
        basin_arr.attrs["_ARRAY_DIMENSIONS"] = ["basin"]

        root.attrs["coordinates"] = "basin time"
        self._write_zarr_units(root, "dynamic")
        print(f"Timeseries zarr written to: {out}")

    @property
    def _attributes_cache_filename(self):
        return "camels_gb_attributes.nc"

    @property
    def _timeseries_cache_filename(self):
        return "camels_gb_timeseries.nc"

    @property
    def default_t_range(self):
        return ["1970-10-01", "2015-09-30"]

    # get the information of features from dataset file"CAMELSGB_EIDC_SupportingDocumentation"
    _subclass_static_definitions = {
        "p_mean": {"specific_name": "p_mean", "unit": "mm/day"},
        "area": {"specific_name": "area_km2", "unit": "km^2"},
        "gauge_lat": {"specific_name": "lat", "unit": "degree"},
        "gauge_lon": {"specific_name": "long", "unit": "degree"},
        "elev_mean": {"specific_name": "elev_mean", "unit": "m"},
        "pet_mean": {"specific_name": "pet_mean", "unit": "mm/day"},
    }

    _dynamic_variable_mapping = {
        StandardVariable.STREAMFLOW: {
            "default_source": "hydrological",
            "sources": {
                "hydrological": {"specific_name": "q_cms_obs", "unit": "m^3/s"},
                "depth_based": {"specific_name": "q_mm_obs", "unit": "mm/day"},
            },
        },
        StandardVariable.PRECIPITATION: {
            "default_source": "meteorological",
            "sources": {
                "meteorological": {"specific_name": "pcp_mm", "unit": "mm/day"},
            },
        },
        StandardVariable.TEMPERATURE_MEAN: {
            "default_source": "meteorological",
            "sources": {
                "meteorological": {"specific_name": "airtemp_C_mean", "unit": "°C"},
            },
        },
        StandardVariable.POTENTIAL_EVAPOTRANSPIRATION: {
            "default_source": "meteorological",
            "sources": {
                "meteorological": {"specific_name": "pet_mm", "unit": "mm/day"},
                "with_interception": {
                    "specific_name": "pet_mm_intercep",
                    "unit": "mm/day",
                },
            },
        },
        StandardVariable.RELATIVE_HUMIDITY: {
            "default_source": "meteorological",
            "sources": {
                "meteorological": {"specific_name": "rh_%", "unit": "g/kg"},
            },
        },
        StandardVariable.SOLAR_RADIATION: {
            "default_source": "meteorological",
            "sources": {
                "meteorological": {"specific_name": "solrad_wm2", "unit": "W/m^2"},
            },
        },
        StandardVariable.LONGWAVE_SOLAR_RADIATION: {
            "default_source": "meteorological",
            "sources": {
                "meteorological": {"specific_name": "lwsolrad_wm2", "unit": "W/m^2"},
            },
        },
        StandardVariable.WIND_SPEED: {
            "default_source": "meteorological",
            "sources": {
                "meteorological": {"specific_name": "windspeed_mps", "unit": "m/s"},
            },
        },
    }

default_t_range property

__init__(uri, region=None, download=False)

Initialize CAMELS_GB dataset.

Parameters:

Name	Type	Description	Default
uri	str	Path to the data directory	required
region	Optional[str]	Geographic region identifier (optional)	None
download	bool	Whether to download data automatically (default: False)	False

Source code in hydrodataset/camels_gb.py

def __init__(
    self, uri: str, region: Optional[str] = None, download: bool = False
) -> None:
    """Initialize CAMELS_GB dataset.

    Args:
        uri: Path to the data directory
        region: Geographic region identifier (optional)
        download: Whether to download data automatically (default: False)
    """
    super().__init__(uri)
    self.region = region
    self.download = download
    if not str(uri).startswith("s3://"):
        self.aqua_fetch = CAMELS_GB(uri)

read_object_ids()

Source code in hydrodataset/camels_gb.py

def read_object_ids(self) -> np.ndarray:
    uri = str(self.data_source_dir).rstrip("/")
    ts_rel = f"{self._DATA_REL}/timeseries"
    if self._is_cloud():
        fs = self._make_s3fs()
        names = [p.split("/")[-1] for p in fs.ls(f"{uri}/{ts_rel}".removeprefix("s3://"))]
    else:
        names = os.listdir(os.path.join(uri, *ts_rel.split("/")))
    ids = sorted(set(
        n.replace("CAMELS_GB_hydromet_timeseries_", "").split("_")[0]
        for n in names if n.startswith("CAMELS_GB_hydromet_timeseries_")
    ))
    return np.array(ids)