x轴时间序列中的分组日期

Question

我试图得到我的421个连续日期（显示在x轴），分为一个月。因此，我不想把一月份的31天贴上标签，我只想把这31天贴上一个标签，称为“2000年1月”，以此类推

我会包括一个图像，但我需要更高的代表。所以，y轴是纬度和x轴是每个月，作为一个时间序列。需要帮忙吗

import numpy as np
from netCDF4 import Dataset
from matplotlib.dates import date2num
from datetime import datetime, timedelta
from netCDF4 import num2date, date2num, date2index

### by defining the directory pathway ###
expname='xnsbi'
inpath = 'E://Data Files (NetCDF)/'+expname+'/Monthly_AOD/'

mnames=    ['0sep','0oct','0nov','0dec','1jan','1feb','1mar','1apr','1may','1jun','1jul', '1aug','1sep','1oct','1nov']

######################### Extracting the data for the plots 

### Looping the variables needed to be extracted for the different months ###
Dates = []
array = []
for name in mnames:
   infile= inpath+expname+'a_pd200'+name+'sAODtracersMDSJamesB.nc' # Complete 
#the pathway to loop all files # 
   vn=Dataset(infile)
   lon       = vn.variables['longitude'][:]
   lat      = vn.variables['latitude'][:]
   time      = vn.variables['t'][:]
   aod550 = vn.variables['aod'][:]

  ### Set the time and date of each plots ####
   t_unit="days since 2000-09-01T00:00:00Z"
   t_cal =  "360_day"
   dates =num2date(time,units=t_unit,calendar=t_cal)
   fmt = '%m/%Y'
   label = dates[0].strftime(fmt)
   print(label)
   ntime=len(time)

   Mlon = np.mean(aod550,axis=1)
   array.append(Mlon)
   fig = plt.figure(figsize=(15.745,15), edgecolor='w')

在这里你可以看到连续421天。这在我的x轴上绘制了421个不同的日期（非常模糊）

   sdate=str(label)
   Dates.append(sdate)
data = np.zeros((145,421))   # For the zonal mean
for i in range(421):
   data[:,i] = array[i]

######## Construct the plot 
cs = plt.contourf(Dates,lat,data,cmap='jet')