Matlab处理气象数据（一）读取NCEP数据数据获取读取

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我是靠谱客的博主内向小丸子，最近开发中收集的这篇文章主要介绍Matlab处理气象数据（一）读取NCEP数据数据获取读取，觉得挺不错的，现在分享给大家，希望可以做个参考。

概述

数据获取

NCEP数据air.2m.mon.mean.nc，下载地址

读取

使用matlab命令读取NCEP数据。

常用的读取NC头文件的命令是 nc_dump 和 ncdisp 。

执行nc_dump命令：

nc_dump('E:数据空间数据NECPair.2m.mon.mean.nc ')

得到如下结果：

NetCDF-3 Classic E:数据空间数据NECPair.2m.mon.mean.nc {
dimensions:
lon = 192 ;
lat = 94 ;
level = 1 ;
nbnds = 2 ;
time = UNLIMITED ; (420 currently)
variables:
// Preference 'PRESERVE_FVD':
false,
// dimensions consistent with ncBrowse, not with native MATLAB netcdf package.
single level(level), shape = [1]
level:units = "m" ;
level:actual_range = 2.000000 2.000000 f;
level:long_name = "Level" ;
level:positive = "up" ;
level:axis = "Z" ;
level:coordinate_defines = "point" ;
single lat(lat), shape = [94]
lat:units = "degrees_north" ;
lat:actual_range = 88.542000 -88.542000 f;
lat:long_name = "Latitude" ;
lat:standard_name = "latitude" ;
lat:axis = "Y" ;
lat:coordinate_defines = "point" ;
single lon(lon), shape = [192]
lon:units = "degrees_east" ;
lon:long_name = "Longitude" ;
lon:actual_range = 0.000000 358.125000 f;
lon:standard_name = "longitude" ;
lon:axis = "X" ;
lon:coordinate_defines = "point" ;
double time(time), shape = [420]
time:units = "hours since 1800-1-1 00:00:00" ;
time:long_name = "Time" ;
time:actual_range = 1.56907e+06 1.87514e+06 ;
time:delta_t = "0000-01-00 00:00:00" ;
time:avg_period = "0000-01-00 00:00:00" ;
time:prev_avg_period = "0000-00-01 00:00:00" ;
time:standard_name = "time" ;
time:axis = "T" ;
time:coordinate_defines = "start" ;
time:bounds = "time_bnds" ;
double time_bnds(time,nbnds), shape = [420 2]
time_bnds:long_name = "Time Boundaries" ;
int16 air(time,level,lat,lon), shape = [420 1 94 192]
air:long_name = "Monthly Mean of Forecast of Air temperature at 2 m" ;
air:valid_range = -32765 -1765 s;
air:unpacked_valid_range = 120.000000 430.000000 f;
air:actual_range = 197.623840 313.472626 f;
air:units = "degK" ;
air:add_offset = 447.649994 f;
air:scale_factor = 0.010000 f;
air:missing_value = 32766 s;
air:_FillValue = -32767 s;
air:precision = 2 s;
air:least_significant_digit = 1 s;
air:GRIB_id = 11 s;
air:GRIB_name = "TMP" ;
air:var_desc = "Air temperature" ;
air:dataset = "NCEP/DOE AMIP-II Reanalysis (Reanalysis-2) Monthly Averages" ;
air:level_desc = "2 m" ;
air:statistic = "Mean" ;
air:parent_stat = "Individual Obs" ;
air:standard_name = "air_temperature" ;
air:cell_methods = "time: mean (interval: 6 hours to daily) time: mean (interval: 1 day to monthly)" ;
//global attributes:
:Conventions = "CF-1.0" ;
:title = "Monthly NCEP/DOE Reanalysis 2" ;
:history = "created 2002/03 by Hoop (netCDF2.3)" ;
:comments = "Data is from
NCEP/DOE AMIP-II Reanalysis (Reanalysis-2)
(4x/day).
Data interpolated from model (sigma) surfaces to gaussian grid." ;
:platform = "Model" ;
:source = "NCEP/DOE AMIP-II Reanalysis (Reanalysis-2) Model" ;
:institution = "National Centers for Environmental Prediction" ;
:references = "http://wesley.wwb.noaa.gov/reanalysis2/
http://www.esrl.noaa.gov/psd/data/gridded/data.ncep.reanalysis2.html" ;

执行ncdisp命令：

ncdisp('E:数据空间数据NECPair.2m.mon.mean.nc ')
Time_bndsData
= ncread('E:数据空间数据NECPair.2m.mon.mean.nc','time_bnds'); %读入变量time_bnds

得到以下结果：

Source:
E:数据空间数据NECPair.2m.mon.mean.nc
Format:
classic
Global Attributes:
Conventions = 'CF-1.0'
title
= 'Monthly NCEP/DOE Reanalysis 2'
history
= 'created 2002/03 by Hoop (netCDF2.3)'
comments
= 'Data is from
NCEP/DOE AMIP-II Reanalysis (Reanalysis-2)
(4x/day).
Data interpolated from model (sigma) surfaces to gaussian grid.'
platform
= 'Model'
source
= 'NCEP/DOE AMIP-II Reanalysis (Reanalysis-2) Model'
institution = 'National Centers for Environmental Prediction'
references
= 'http://wesley.wwb.noaa.gov/reanalysis2/
http://www.esrl.noaa.gov/psd/data/gridded/data.ncep.reanalysis2.html'
Dimensions:
lon
= 192
lat
= 94
level = 1
nbnds = 2
time
= 420
(UNLIMITED)
Variables:
level
Size:
1x1
Dimensions: level
Datatype:
single
Attributes:
units
= 'm'
actual_range
= [2.00e+00 2.00e+00]
long_name
= 'Level'
positive
= 'up'
axis
= 'Z'
coordinate_defines = 'point'
lat
Size:
94x1
Dimensions: lat
Datatype:
single
Attributes:
units
= 'degrees_north'
actual_range
= [8.85e+01 -8.85e+01]
long_name
= 'Latitude'
standard_name
= 'latitude'
axis
= 'Y'
coordinate_defines = 'point'
lon
Size:
192x1
Dimensions: lon
Datatype:
single
Attributes:
units
= 'degrees_east'
long_name
= 'Longitude'
actual_range
= [0.00e+00 3.58e+02]
standard_name
= 'longitude'
axis
= 'X'
coordinate_defines = 'point'
time
Size:
420x1
Dimensions: time
Datatype:
double
Attributes:
units
= 'hours since 1800-1-1 00:00:00'
long_name
= 'Time'
actual_range
= [1.57e+06 1.88e+06]
delta_t
= '0000-01-00 00:00:00'
avg_period
= '0000-01-00 00:00:00'
prev_avg_period
= '0000-00-01 00:00:00'
standard_name
= 'time'
axis
= 'T'
coordinate_defines = 'start'
bounds
= 'time_bnds'
time_bnds
Size:
2x420
Dimensions: nbnds,time
Datatype:
double
Attributes:
long_name = 'Time Boundaries'
air
Size:
192x94x1x420
Dimensions: lon,lat,level,time
Datatype:
int16
Attributes:
long_name
= 'Monthly Mean of Forecast of Air temperature at 2 m'
valid_range
= [-3.28e+04 -1.77e+03]
unpacked_valid_range
= [1.20e+02 4.30e+02]
actual_range
= [1.98e+02 3.13e+02]
units
= 'degK'
add_offset
= 448
scale_factor
= 0.01
missing_value
= 3.28e+04
_FillValue
= -3.28e+04
precision
= 2
least_significant_digit = 1
GRIB_id
= 11
GRIB_name
= 'TMP'
var_desc
= 'Air temperature'
dataset
= 'NCEP/DOE AMIP-II Reanalysis (Reanalysis-2) Monthly Averages'
level_desc
= '2 m'
statistic
= 'Mean'
parent_stat
= 'Individual Obs'
standard_name
= 'air_temperature'
cell_methods
= 'time: mean (interval: 6 hours to daily) time: mean (interval: 1 day to monthly)'

另外，还可以用nc_varget来读取数据，如：

lon=nc_varget('E:数据空间数据NECPair.2m.mon.mean.nc','lon');%查看经度的范围
lat=nc_varget('E:数据空间数据NECPair.2m.mon.mean.nc','lat'); %查看纬度的范围
data=nc_varget('E:数据空间数据NECPair.2m.mon.mean.nc','air',[0 0 0 0],[420 1 94 192]);%取值范围从[0 0 0 0]到[time level lat 1on]

由以上命令可以得知，此NCEP数据为192*94*420的高维数组，经度范围是[0,358.1250]，纬度范围是[88.5420,-88.5420]，时间范围在数据里没给出，但从网站的数据说明中可以知道是1979年1月到2013年12月。（2016年1月13日查询到，此数据已经更新到了2015年7月）。

相关链接：
Matlab处理气象数据——目录