|
| 1 | +"""NASA POWER T2M (2-meter air temperature) Data Converter Module. |
| 2 | +
|
| 3 | +This module provides functionality for converting NASA POWER 2-meter air temperature |
| 4 | +data to GeoCroissant format. It specializes in handling T2M measurements and their |
| 5 | +associated metadata, making the data accessible within the GeoCroissant framework. |
| 6 | +""" |
| 7 | + |
| 8 | +import hashlib |
| 9 | +import json |
| 10 | +from typing import Any, Dict |
| 11 | + |
| 12 | +import xarray as xr |
| 13 | + |
| 14 | + |
| 15 | +class T2MCroissantConverter: |
| 16 | + """NASA POWER T2M data for the year 2020 to GeoCroissant format.""" |
| 17 | + |
| 18 | + def __init__( |
| 19 | + self, |
| 20 | + zarr_url: str = "s3://nasa-power/merra2/temporal/power_merra2_monthly_temporal_utc.zarr/", |
| 21 | + ): |
| 22 | + """Initialize the converter with the Zarr URL. |
| 23 | +
|
| 24 | + Args: |
| 25 | + zarr_url: URL to the NASA POWER Zarr dataset. |
| 26 | + """ |
| 27 | + self.zarr_url = zarr_url |
| 28 | + self.ds_full = None |
| 29 | + self.ds_2020 = None |
| 30 | + self.variable = "T2M" |
| 31 | + self.year = 2020 |
| 32 | + |
| 33 | + def load_dataset(self) -> bool: |
| 34 | + """Load the full dataset from S3 and subset T2M for 2020.""" |
| 35 | + try: |
| 36 | + print(f"Loading NASA POWER dataset from {self.zarr_url}...") |
| 37 | + self.ds_full = xr.open_zarr(self.zarr_url, storage_options={"anon": True}) |
| 38 | + # Subset for 2020 only |
| 39 | + self.ds_2020 = self.ds_full.sel( |
| 40 | + time=slice("{self.year}-01-01", "{self.year}-12-31") |
| 41 | + ) |
| 42 | + print("Dataset loaded successfully!") |
| 43 | + print(" - Dimensions: {self.ds_2020.dims}") |
| 44 | + print(" - T2M shape: {self.ds_2020[self.variable].shape}") |
| 45 | + print( |
| 46 | + " - Time range: {self.ds_2020.time.values[0]} to" |
| 47 | + " {self.ds_2020.time.values[-1]}" |
| 48 | + ) |
| 49 | + return True |
| 50 | + except Exception: |
| 51 | + print("Error loading dataset: {e}") |
| 52 | + return False |
| 53 | + |
| 54 | + def generate_checksum(self, content: str) -> str: |
| 55 | + """Generate MD5 checksum for content.""" |
| 56 | + return hashlib.md5(content.encode("utf-8")).hexdigest() |
| 57 | + |
| 58 | + def create_croissant_metadata( |
| 59 | + self, output_file: str = "T2M_2020_croissant.json" |
| 60 | + ) -> Dict[str, Any]: |
| 61 | + """Create GeoCroissant metadata for the T2M 2020 data. |
| 62 | +
|
| 63 | + Args: |
| 64 | + output_file: Output file path. |
| 65 | +
|
| 66 | + Returns: |
| 67 | + dict: GeoCroissant metadata. |
| 68 | + """ |
| 69 | + if self.ds_2020 is None: |
| 70 | + print("Error: No 2020 data available. Call load_dataset() first.") |
| 71 | + return {} |
| 72 | + |
| 73 | + t2m_data = self.ds_2020[self.variable] |
| 74 | + var_metadata = { |
| 75 | + "long_name": t2m_data.attrs.get("long_name", "Temperature at 2 Meters"), |
| 76 | + "units": t2m_data.attrs.get("units", "C"), |
| 77 | + "valid_min": t2m_data.attrs.get("valid_min", -125.0), |
| 78 | + "valid_max": t2m_data.attrs.get("valid_max", 80.0), |
| 79 | + "standard_name": t2m_data.attrs.get( |
| 80 | + "standard_name", "Temperature_at_2_Meters" |
| 81 | + ), |
| 82 | + "definition": t2m_data.attrs.get( |
| 83 | + "definition", |
| 84 | + "The average air (dry bulb) temperature at 2 meters above the surface" |
| 85 | + " of the earth.", |
| 86 | + ), |
| 87 | + "status": t2m_data.attrs.get("status", "official"), |
| 88 | + "significant_digits": t2m_data.attrs.get("significant_digits", 2), |
| 89 | + "cell_methods": t2m_data.attrs.get("cell_methods", "time: mean"), |
| 90 | + } |
| 91 | + |
| 92 | + # Calculate sizes |
| 93 | + _ = self.ds_2020.nbytes / 1e9 |
| 94 | + t2m_size_mb = t2m_data.nbytes / 1e6 |
| 95 | + _ = t2m_size_mb / 12 |
| 96 | + |
| 97 | + # Generate checksum |
| 98 | + hash_input = f"{self.zarr_url}{self.year}{self.variable}" |
| 99 | + md5_hash = self.generate_checksum(hash_input) |
| 100 | + |
| 101 | + croissant = { |
| 102 | + "@context": { |
| 103 | + "@language": "en", |
| 104 | + "@vocab": "https://schema.org/", |
| 105 | + "citeAs": "cr:citeAs", |
| 106 | + "column": "cr:column", |
| 107 | + "conformsTo": "dct:conformsTo", |
| 108 | + "cr": "http://mlcommons.org/croissant/", |
| 109 | + "geocr": "http://mlcommons.org/croissant/geocr/", |
| 110 | + "rai": "http://mlcommons.org/croissant/RAI/", |
| 111 | + "dct": "http://purl.org/dc/terms/", |
| 112 | + "sc": "https://schema.org/", |
| 113 | + "data": {"@id": "cr:data", "@type": "@json"}, |
| 114 | + "examples": {"@id": "cr:examples", "@type": "@json"}, |
| 115 | + "dataBiases": "cr:dataBiases", |
| 116 | + "dataCollection": "cr:dataCollection", |
| 117 | + "dataType": {"@id": "cr:dataType", "@type": "@vocab"}, |
| 118 | + "extract": "cr:extract", |
| 119 | + "field": "cr:field", |
| 120 | + "fileProperty": "cr:fileProperty", |
| 121 | + "fileObject": "cr:fileObject", |
| 122 | + "fileSet": "cr:fileSet", |
| 123 | + "format": "cr:format", |
| 124 | + "includes": "cr:includes", |
| 125 | + "isLiveDataset": "cr:isLiveDataset", |
| 126 | + "jsonPath": "cr:jsonPath", |
| 127 | + "key": "cr:key", |
| 128 | + "md5": "cr:md5", |
| 129 | + "parentField": "cr:parentField", |
| 130 | + "path": "cr:path", |
| 131 | + "personalSensitiveInformation": "cr:personalSensitiveInformation", |
| 132 | + "recordSet": "cr:recordSet", |
| 133 | + "references": "cr:references", |
| 134 | + "regex": "cr:regex", |
| 135 | + "repeated": "cr:repeated", |
| 136 | + "replace": "cr:replace", |
| 137 | + "samplingRate": "cr:samplingRate", |
| 138 | + "separator": "cr:separator", |
| 139 | + "source": "cr:source", |
| 140 | + "subField": "cr:subField", |
| 141 | + "transform": "cr:transform", |
| 142 | + }, |
| 143 | + "@type": "sc:Dataset", |
| 144 | + "name": "NASA-POWER-T2M-Monthly-Time-Series-2020", |
| 145 | + "alternateName": ["nasa-power-t2m-2020", "POWER-T2M-2020"], |
| 146 | + "description": ( |
| 147 | + "Monthly time series of Temperature at 2 Meters (T2M) for 2020 from" |
| 148 | + " NASA POWER dataset. This dataset provides global temperature data at" |
| 149 | + " 0.5° latitude and 0.625° longitude resolution with monthly temporal" |
| 150 | + " resolution." |
| 151 | + ), |
| 152 | + "conformsTo": "http://mlcommons.org/croissant/1.0", |
| 153 | + "version": "1.0.0", |
| 154 | + "url": "https://power.larc.nasa.gov", |
| 155 | + "license": "https://creativecommons.org/licenses/by/4.0/", |
| 156 | + "creator": { |
| 157 | + "@type": "Organization", |
| 158 | + "name": "NASA Langley Research Center (LaRC)", |
| 159 | + "url": "https://power.larc.nasa.gov", |
| 160 | + }, |
| 161 | + "keywords": [ |
| 162 | + "Temperature", |
| 163 | + "Climate", |
| 164 | + "NASA", |
| 165 | + "POWER", |
| 166 | + "2020", |
| 167 | + "Monthly", |
| 168 | + "Geospatial", |
| 169 | + "Earth Science", |
| 170 | + "Meteorology", |
| 171 | + "Climate Data", |
| 172 | + ], |
| 173 | + "citeAs": ( |
| 174 | + "NASA POWER Project. Prediction Of Worldwide Energy Resource (POWER)" |
| 175 | + " Project. NASA Langley Research Center." |
| 176 | + ), |
| 177 | + "geocr:BoundingBox": [ |
| 178 | + self.ds_full.attrs.get("geospatial_lon_min", -180.0), |
| 179 | + self.ds_full.attrs.get("geospatial_lat_min", -90.0), |
| 180 | + self.ds_full.attrs.get("geospatial_lon_max", 180.0), |
| 181 | + self.ds_full.attrs.get("geospatial_lat_max", 90.0), |
| 182 | + ], |
| 183 | + "geocr:temporalExtent": { |
| 184 | + "startDate": "2020-01-01T00:00:00Z", |
| 185 | + "endDate": "2020-12-31T23:59:59Z", |
| 186 | + }, |
| 187 | + "geocr:spatialResolution": "0.5° lat × 0.625° lon", |
| 188 | + "geocr:coordinateReferenceSystem": "EPSG:4326", |
| 189 | + "geocr:mlTask": { |
| 190 | + "@type": "geocr:Regression", |
| 191 | + "taskType": "climate_prediction", |
| 192 | + "evaluationMetric": "RMSE", |
| 193 | + "applicationDomain": "climate_monitoring", |
| 194 | + }, |
| 195 | + "distribution": [ |
| 196 | + { |
| 197 | + "@type": "cr:FileObject", |
| 198 | + "@id": "zarr-store-t2m-2020", |
| 199 | + "name": "zarr-store-t2m-2020", |
| 200 | + "description": ( |
| 201 | + "Zarr datacube for NASA POWER T2M data for the year 2020" |
| 202 | + ), |
| 203 | + "contentUrl": self.zarr_url, |
| 204 | + "encodingFormat": "application/x-zarr", |
| 205 | + "md5": md5_hash, |
| 206 | + } |
| 207 | + ], |
| 208 | + "datePublished": "2020-12-31", |
| 209 | + "recordSet": [ |
| 210 | + { |
| 211 | + "@type": "cr:RecordSet", |
| 212 | + "@id": "nasa_power_t2m_2020", |
| 213 | + "name": "nasa_power_t2m_2020", |
| 214 | + "description": "NASA POWER T2M climate data for the year 2020", |
| 215 | + "field": [], |
| 216 | + } |
| 217 | + ], |
| 218 | + } |
| 219 | + |
| 220 | + # Add fields |
| 221 | + fields = croissant["recordSet"][0]["field"] |
| 222 | + |
| 223 | + # Add coordinate fields |
| 224 | + for coord_name, coord in self.ds_2020.coords.items(): |
| 225 | + coord_field = { |
| 226 | + "@type": "cr:Field", |
| 227 | + "@id": "nasa_power_t2m_2020/{coord_name}", |
| 228 | + "name": "nasa_power_t2m_2020/{coord_name}", |
| 229 | + "description": "Coordinate: {coord_name}", |
| 230 | + "dataType": "sc:Float" if coord.dtype.kind == "" else "sc:Date", |
| 231 | + "source": { |
| 232 | + "fileObject": {"@id": "zarr-store-t2m-2020"}, |
| 233 | + "extract": {"jsonPath": "$.{coord_name}"}, |
| 234 | + }, |
| 235 | + "geocr:dataShape": list(coord.shape), |
| 236 | + "geocr:validRange": ( |
| 237 | + { |
| 238 | + "min": ( |
| 239 | + -90.0 |
| 240 | + if coord_name == "lat" |
| 241 | + else -180.0 if coord_name == "lon" else None |
| 242 | + ), |
| 243 | + "max": ( |
| 244 | + 90.0 |
| 245 | + if coord_name == "lat" |
| 246 | + else 180.0 if coord_name == "lon" else None |
| 247 | + ), |
| 248 | + } |
| 249 | + if coord_name in ["lat", "lon"] |
| 250 | + else None |
| 251 | + ), |
| 252 | + "geocr:units": ( |
| 253 | + "degrees_north" |
| 254 | + if coord_name == "lat" |
| 255 | + else "degrees_east" if coord_name == "lon" else None |
| 256 | + ), |
| 257 | + } |
| 258 | + # Remove None values |
| 259 | + coord_field = {k: v for k, v in coord_field.items() if v is not None} |
| 260 | + fields.append(coord_field) |
| 261 | + |
| 262 | + # Main T2M field |
| 263 | + main_field = { |
| 264 | + "@type": "cr:Field", |
| 265 | + "@id": "nasa_power_t2m_2020/T2M", |
| 266 | + "name": "nasa_power_t2m_2020/T2M", |
| 267 | + "description": var_metadata["long_name"], |
| 268 | + "dataType": "sc:Float", |
| 269 | + "source": { |
| 270 | + "fileObject": {"@id": "zarr-store-t2m-2020"}, |
| 271 | + "extract": {"jsonPath": "$.T2M"}, |
| 272 | + }, |
| 273 | + "geocr:dataShape": list(t2m_data.shape), |
| 274 | + "geocr:validRange": { |
| 275 | + "min": float(var_metadata["valid_min"]), |
| 276 | + "max": float(var_metadata["valid_max"]), |
| 277 | + }, |
| 278 | + "geocr:units": var_metadata["units"], |
| 279 | + "geocr:standardName": var_metadata["standard_name"], |
| 280 | + "geocr:definition": var_metadata["definition"], |
| 281 | + "geocr:cellMethods": var_metadata["cell_methods"], |
| 282 | + } |
| 283 | + fields.append(main_field) |
| 284 | + |
| 285 | + # Save metadata |
| 286 | + with open(output_file, "w", encoding="utf-8") as f: |
| 287 | + json.dump(croissant, f, indent=2, ensure_ascii=False) |
| 288 | + |
| 289 | + print("GeoCroissant metadata saved to {output_file}") |
| 290 | + print("Total fields: {len(fields)}") |
| 291 | + |
| 292 | + return croissant |
| 293 | + |
| 294 | + def convert(self, output_file: str = "T2M_2020_croissant.json") -> Dict[str, Any]: |
| 295 | + """Complete conversion pipeline for T2M 2020. |
| 296 | +
|
| 297 | + Args: |
| 298 | + output_file: Output file path. |
| 299 | +
|
| 300 | + Returns: |
| 301 | + dict: GeoCroissant metadata. |
| 302 | + """ |
| 303 | + print(f"Starting conversion for T2M {self.year}...") |
| 304 | + if not self.load_dataset(): |
| 305 | + return {} |
| 306 | + |
| 307 | + metadata = self.create_croissant_metadata(output_file) |
| 308 | + print("Conversion completed successfully!") |
| 309 | + return metadata |
| 310 | + |
| 311 | + |
| 312 | +# Example usage in notebook: |
| 313 | +converter = T2MCroissantConverter() |
| 314 | +metadata = converter.convert() |
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