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I am trying to understand on what @Rainfall.NZ saying on this answer: https://stackoverflow.com/a/67258594 related to ERA5-Land Hourly precipitation and ERA5 Reanalysis Hourly precipitation are different. See https://confluence.ecmwf.int/pages/viewpage.action?pageId=197702790

From above link, row 5 column 7:

tp [mm]=tpd+1 00UTC [m]⋅1000 where d is the day for which the average flux is being computed. The time step labelled d+1 00UTC should also be taken because it contains the accumulated flux over the previous 24 hours.

I want to make sure if the step below is correct to get daily total precipitation:

  1. Download the data using API, which include time 00:00 and 23:00 only using below script
import cdsapi

c = cdsapi.Client()

years = list(range(1950, 2021))

for year in years:
    c.retrieve(
    'reanalysis-era5-land',
    {
        'variable': [
            'total_precipitation',
        ],
        'year': str(year),
        'month': [
            '01', '02', '03',
            '04', '05', '06',
            '07', '08', '09',
            '10', '11', '12',
        ],
        'day': [
            '01', '02', '03',
            '04', '05', '06',
            '07', '08', '09',
            '10', '11', '12',
            '13', '14', '15',
            '16', '17', '18',
            '19', '20', '21',
            '22', '23', '24',
            '25', '26', '27',
            '28', '29', '30',
            '31',
        ],
        'time': [
            '00:00', '23:00',
        ],
        'area': [
            11, 90, -13,
            145,
        ],
        'format': 'netcdf',
    },
    'era5land_' + str(year) + '.nc')

    print('era5land_' + str(year) + '.nc' + ' downloaded.')
  1. Using CDO shifttime to get the daily total
cdo daysum -shifttime,-1hour era5land_precip.nc4 temp.nc4
cdo -shifttime,1hour temp.nc4 era5land_precip.nc4
user97103
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  • Please rewrite this as a self-contained question. Right now there is literally no way to understand what you are asking without clicking another question and doing a lot of guess work about what your problem is – Robert Wilson Jan 23 '23 at 09:00

1 Answers1

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After read carefully from @rainfall.nz post and the documentation, I think I only need to download for hour 00, and do cdo -shifttime,-1hour in.nc out.nc

I also tested by downloading all hourly data for 3 consecutive days and found the data on day3_00 is the total rainfall for 24h for day2.

user97103
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