How to convert the unit in netcdf 4 /u/Vriherre Python Education

I want to use the Climate Indices in Python package by James Adams to calculate the Spei. For every month since 1994 to 2024. For this it will only take input data with the unit “millimeters” but the unit in my data is “m” how can i convert the unit? My variable looks like this:

float tp(time=370, lat=212, lon=409); :_FillValue = NaNf; // float :GRIB_paramId = 228L; // long :GRIB_dataType = "fc"; :GRIB_numberOfPoints = 86708L; // long :GRIB_typeOfLevel = "surface"; :GRIB_stepUnits = 1L; // long :GRIB_stepType = "avgas"; :GRIB_gridType = "regular_ll"; :GRIB_uvRelativeToGrid = 0L; // long :GRIB_NV = 0L; // long :GRIB_Nx = 409L; // long :GRIB_Ny = 212L; // long :GRIB_cfName = "unknown"; :GRIB_cfVarName = "tp"; :GRIB_gridDefinitionDescription = "Latitude/Longitude Grid"; :GRIB_iDirectionIncrementInDegrees = 0.1; // double :GRIB_iScansNegatively = 0L; // long :GRIB_jDirectionIncrementInDegrees = 0.1; // double :GRIB_jPointsAreConsecutive = 0L; // long :GRIB_jScansPositively = 0L; // long :GRIB_latitudeOfFirstGridPointInDegrees = 55.4; // double :GRIB_latitudeOfLastGridPointInDegrees = 34.3; // double :GRIB_longitudeOfFirstGridPointInDegrees = 46.5; // double :GRIB_longitudeOfLastGridPointInDegrees = 87.3; // double :GRIB_missingValue = 3.4028234663852886E38; // double :GRIB_name = "Total precipitation"; :GRIB_shortName = "tp"; :GRIB_totalNumber = 0L; // long :GRIB_units = "m"; :long_name = "Total precipitation"; :units = "m"; :standard_name = "unknown"; :GRIB_surface = 0.0; // double :coordinates = "number time latitude longitude expver"; :_ChunkSizes = 185U, 106U, 205U; // uintfloat tp(time=370, lat=212, lon=409); :_FillValue = NaNf; // float :GRIB_paramId = 228L; // long :GRIB_dataType = "fc"; :GRIB_numberOfPoints = 86708L; // long :GRIB_typeOfLevel = "surface"; :GRIB_stepUnits = 1L; // long :GRIB_stepType = "avgas"; :GRIB_gridType = "regular_ll"; :GRIB_uvRelativeToGrid = 0L; // long :GRIB_NV = 0L; // long :GRIB_Nx = 409L; // long :GRIB_Ny = 212L; // long :GRIB_cfName = "unknown"; :GRIB_cfVarName = "tp"; :GRIB_gridDefinitionDescription = "Latitude/Longitude Grid"; :GRIB_iDirectionIncrementInDegrees = 0.1; // double :GRIB_iScansNegatively = 0L; // long :GRIB_jDirectionIncrementInDegrees = 0.1; // double :GRIB_jPointsAreConsecutive = 0L; // long :GRIB_jScansPositively = 0L; // long :GRIB_latitudeOfFirstGridPointInDegrees = 55.4; // double :GRIB_latitudeOfLastGridPointInDegrees = 34.3; // double :GRIB_longitudeOfFirstGridPointInDegrees = 46.5; // double :GRIB_longitudeOfLastGridPointInDegrees = 87.3; // double :GRIB_missingValue = 3.4028234663852886E38; // double :GRIB_name = "Total precipitation"; :GRIB_shortName = "tp"; :GRIB_totalNumber = 0L; // long :GRIB_units = "m"; :long_name = "Total precipitation"; :units = "m"; :standard_name = "unknown"; :GRIB_surface = 0.0; // double :coordinates = "number time latitude longitude expver"; :_ChunkSizes = 185U, 106U, 205U; // uint 

I want to use the Climate Indices in Python package by James Adams to calculate the Spei. For every month since 1994 to 2024. For this it will only take input data with the unit “millimeters” but the unit in my data is “m” how can i convert the unit? My variable looks like this:

float tp(time=370, lat=212, lon=409); :_FillValue = NaNf; // float :GRIB_paramId = 228L; // long :GRIB_dataType = "fc"; :GRIB_numberOfPoints = 86708L; // long :GRIB_typeOfLevel = "surface"; :GRIB_stepUnits = 1L; // long :GRIB_stepType = "avgas"; :GRIB_gridType = "regular_ll"; :GRIB_uvRelativeToGrid = 0L; // long :GRIB_NV = 0L; // long :GRIB_Nx = 409L; // long :GRIB_Ny = 212L; // long :GRIB_cfName = "unknown"; :GRIB_cfVarName = "tp"; :GRIB_gridDefinitionDescription = "Latitude/Longitude Grid"; :GRIB_iDirectionIncrementInDegrees = 0.1; // double :GRIB_iScansNegatively = 0L; // long :GRIB_jDirectionIncrementInDegrees = 0.1; // double :GRIB_jPointsAreConsecutive = 0L; // long :GRIB_jScansPositively = 0L; // long :GRIB_latitudeOfFirstGridPointInDegrees = 55.4; // double :GRIB_latitudeOfLastGridPointInDegrees = 34.3; // double :GRIB_longitudeOfFirstGridPointInDegrees = 46.5; // double :GRIB_longitudeOfLastGridPointInDegrees = 87.3; // double :GRIB_missingValue = 3.4028234663852886E38; // double :GRIB_name = "Total precipitation"; :GRIB_shortName = "tp"; :GRIB_totalNumber = 0L; // long :GRIB_units = "m"; :long_name = "Total precipitation"; :units = "m"; :standard_name = "unknown"; :GRIB_surface = 0.0; // double :coordinates = "number time latitude longitude expver"; :_ChunkSizes = 185U, 106U, 205U; // uintfloat tp(time=370, lat=212, lon=409); :_FillValue = NaNf; // float :GRIB_paramId = 228L; // long :GRIB_dataType = "fc"; :GRIB_numberOfPoints = 86708L; // long :GRIB_typeOfLevel = "surface"; :GRIB_stepUnits = 1L; // long :GRIB_stepType = "avgas"; :GRIB_gridType = "regular_ll"; :GRIB_uvRelativeToGrid = 0L; // long :GRIB_NV = 0L; // long :GRIB_Nx = 409L; // long :GRIB_Ny = 212L; // long :GRIB_cfName = "unknown"; :GRIB_cfVarName = "tp"; :GRIB_gridDefinitionDescription = "Latitude/Longitude Grid"; :GRIB_iDirectionIncrementInDegrees = 0.1; // double :GRIB_iScansNegatively = 0L; // long :GRIB_jDirectionIncrementInDegrees = 0.1; // double :GRIB_jPointsAreConsecutive = 0L; // long :GRIB_jScansPositively = 0L; // long :GRIB_latitudeOfFirstGridPointInDegrees = 55.4; // double :GRIB_latitudeOfLastGridPointInDegrees = 34.3; // double :GRIB_longitudeOfFirstGridPointInDegrees = 46.5; // double :GRIB_longitudeOfLastGridPointInDegrees = 87.3; // double :GRIB_missingValue = 3.4028234663852886E38; // double :GRIB_name = "Total precipitation"; :GRIB_shortName = "tp"; :GRIB_totalNumber = 0L; // long :GRIB_units = "m"; :long_name = "Total precipitation"; :units = "m"; :standard_name = "unknown"; :GRIB_surface = 0.0; // double :coordinates = "number time latitude longitude expver"; :_ChunkSizes = 185U, 106U, 205U; // uint