Question

我已经阅读了有关NetCDF数据的其他解决方案，但是我的数据有些不同，并且我不知道如何从NetCDF提取数据并将其保存为基于电台的CSV文件。数据包括站的最高温度值。我只需要位于纬度：25.74至49.05和经度：-93.44至-116.0的站点即可。时间的格式不同，我只需要时间[7518：43947190]，其中包括1948年的数据。我想创建多个csv文件。每个文件必须是一个站的数据，包括时间，tmax和数据质量标志。如果有人可以提供帮助，我非常感谢。

from netCDF4 import Dataset
dataset=Dataset("D:/ushcn_tmax.nc")

#### Print dimentions #####
print dataset.file_format
print dataset.dimensions.keys()
print dataset.dimensions['name_strlen']
print dataset.dimensions['obs']
print dataset.dimensions['station']

#### Print variables ####
print dataset.variables.keys()
print dataset.variables['LON']
print dataset.variables['LAT']
print dataset.variables['ELEVATION']
print dataset.variables['STATION_NAME']
print dataset.variables['STATION_INDEX']
print dataset.variables['TIME']
print dataset.variables['TMAX']
print dataset.variables['TMAX_MFLAG']
print dataset.variables['TMAX_QFLAG']
print dataset.variables['TMAX_SFLAG']

我的数据的维度和变量可以在这里看到：

NETCDF3_CLASSIC
[u'name_strlen', u'obs', u'station']
<type 'netCDF4._netCDF4.Dimension'>: name = 'name_strlen', size = 50

<type 'netCDF4._netCDF4.Dimension'>: name = 'obs', size = 43947189

<type 'netCDF4._netCDF4.Dimension'>: name = 'station', size = 1218

[u'LON', u'LAT', u'ELEVATION', u'STATION_NAME', u'STATION_INDEX', u'TIME', u'TMAX', u'TMAX_MFLAG', u'TMAX_QFLAG', u'TMAX_SFLAG']
<type 'netCDF4._netCDF4.Variable'>
float32 LON(station)
    standard_name: longitude
    long_name: station longitude
    units: degrees_east
unlimited dimensions: 
current shape = (1218,)
filling off

<type 'netCDF4._netCDF4.Variable'>
float32 LAT(station)
    standard_name: latitude
    long_name: station latitude
    units: degrees_north
unlimited dimensions: 
current shape = (1218,)
filling off

<type 'netCDF4._netCDF4.Variable'>
float64 ELEVATION(station)
    long_name: elevation above the sea level
    standard_name: elevation
    units: m
    positive: up
    axis: Z
unlimited dimensions: 
current shape = (1218,)
filling off

<type 'netCDF4._netCDF4.Variable'>
|S1 STATION_NAME(station, name_strlen)
    long_name: USHCN station name
    cf_role: timeseries_id
unlimited dimensions: 
current shape = (1218, 50)
filling off

<type 'netCDF4._netCDF4.Variable'>
int32 STATION_INDEX(obs)
    long_name: which station this obs is for
    instance_dimension: station
unlimited dimensions: 
current shape = (43947189,)
filling off

<type 'netCDF4._netCDF4.Variable'>
float64 TIME(obs)
    standard_name: time
    long_name: Time
    units: decimal day
    _FillValue: -9999.0
    comment: time calculeted as: year + day_of_year/days_in_year
unlimited dimensions: 
current shape = (43947189,)
filling off

<type 'netCDF4._netCDF4.Variable'>
int32 TMAX(obs)
    standard_name: TMAX
    long_name: maximum temperature
    units: degrees F
    coordinates: time lat lon elevation
    _FillValue: -9999
unlimited dimensions: 
current shape = (43947189,)
filling off

<type 'netCDF4._netCDF4.Variable'>
|S1 TMAX_MFLAG(obs)
    standard_name: TMAX_MFLAG
    long_mane: measurement flag for TMAX
    flag_values:  BDLT
    flag_meanings: Blank = no measurement information applicable; B = precipitation total formed from two 12-hour totals; D = precipitation total formed from four six-hour totals; L = temperature appears to be lagged with respect to reported hour of OBServation; T = trace of precipitation, snowfall, or snow depth
unlimited dimensions: 
current shape = (43947189,)
filling off

<type 'netCDF4._netCDF4.Variable'>
|S1 TMAX_QFLAG(obs)
    standard_name: TMAX_QFLAG
    long_mane: quality flag for TMAX
    flag_values:  ADGIKMNORSTWX
    flag_meanings: Blank = did not fail any quality assurance check; A = failed accumulation total check; D = failed duplicate check; G = failed gap check; I = failed internal consistency check; K = failed streak/frequent-value check; M = failed megaconsistency check; N = failed naught check; O = failed climatological outlier check; R = failed lagged range check; S = failed spatial consistency check; T = failed temporal consistency check; W = temperature too warm for snow; X = failed bounds check;
unlimited dimensions: 
current shape = (43947189,)
filling off

<type 'netCDF4._netCDF4.Variable'>
|S1 TMAX_SFLAG(obs)
    standard_name: TMAX_SFLAG
    long_mane: source flag for TMAX
    flag_values:  0126ABFGHIMQRSX
    flag_meanings: Blank = No source (i.e., data value missing); 0 = U.S. Cooperative Summary of the Day (NCDC DSI-3200); 1 = U.S. Preliminary Cooperative Summary of the Day -- Transmitted; 2 = U.S. Preliminary Cooperative Summary of the Day -- Keyed from paper forms; 6 = CDMP Cooperative Summary of the Day (NCDC DSI-3206); A = U.S. Automated Surface Observing System (ASOS) real-time data (since January 1, 2006); B = U.S. ASOS data for October 2000-December 2005 (NCDC DSI-3211); F = U.S. Fort data; G = Official Global Climate Observing System (GCOS) or other government-supplied data; H = High Plains Regional Climate Center real-time data; I = International collection (non U.S. data received through personal contacts); M = Monthly METAR Extract (additional ASOS data); Q = Data from several African countries that had been 'quarantined', that is, withheld from public release until permission was granted from the respective meteorological services; R = NCDC Reference Network Database (Climate Reference Network and Historical Climatology Network-Modernized); S = Global Summary of the Day (NCDC DSI-9618), NOTE: 'S' values are derived from hourly synoptic reports exchanged on the Global Telecommunications System (GTS).Daily values derived in this fashion may differ significantly from 'true' daily data, particularly for precipitation (i.e., use with caution); X = U.S. First-Order Summary of the Day (NCDC DSI-3210)
unlimited dimensions: 
current shape = (43947189,)
filling off

我尝试使用：

读取数据

xr.open_dataset("D:/ushcn_tmax.nc")
df=dataset.sel(lon=-99.30,lat=32.73,method='nearest')

当提到的经纬度和经度属于一个站时，我收到了错误“ KeyError：'lat'”。有什么方法可以将变量（纬度，经度和时间）转换为尺寸，以便于使用？或以任何方式可以基于桩号作为维度提取数据？任何帮助都非常感谢。

根据工作站

0 个答案: