import numpy as np
s = open ('C:\\Users\\tropomi\\no2_201810.asc').readlines()
print(len(s))
a = np.zeros((1440,2880))
#f = open('10.txt','w+')
for i in range(4,len(s)):
    ii = (i-4)//145*0.125-89.9375
    i_each = (i-4)%145
    for j in range(0,80,4):
        if i_each>0 and int(s[i][j:j+4])>0:
            j_each = j//4
            jj = ((i_each-1)*20+j_each)*0.125-179.9375
            #print(ii,jj,s[i][j:j+4],file=f)
            a[(i-4)//145][(i_each-1)*20+j_each] = int(s[i][j:j+4])
            #a[1339-((i-4)//145)][(i_each-1)*20+j_each] = int(s[i][j:j+4])#可能字符编码的问题
    print(i)
np.savetxt("10.txt", a, fmt="%d", delimiter=" ")
#f.close()

因为第一行的数据是-90°的，而我们希望矩阵的左下角才是，所以需要调换过来，但是，本来应该更容易解决的问题可能由于字符编码的问题总是出错，干脆直接用matlab写个简单的行调换。

clear;
clc;
filename = '.\02.txt';
a=textread(filename);
b=a;
for i=1:1440
    b(1441-i,:)= a(i,:);
end

dlmwrite('02new.txt', b, 'delimiter', ' ','precision', 5,'newline', 'pc')

最后在txt的头部添上信息，可参照ArcMap的说明

ncols 2880
nrows 1440
xllcenter -179.9375
yllcenter -89.9375
cellsize 0.125
NODATA_value 0

之前还写了一个中国区域的

s = open('/Users/heqin/Downloads/tropomi/no2_201809.asc').readlines()
f = open('9.txt','w+')
for i in range(107885,167044): #北纬3度～54度
    ii = (i-4)//145*0.125-89.9375
    i_each = (i-4)%145 #该i在该组的实际第几行
    for j in range(0,80,4):
        if 102 <= i_each <= 127 and int(s[i][j:j+4]) >0: #东经73度～136度
            j_each = j//4 #该j在该组的实际第几列
            jj = ((i_each-1)*20+j_each)*0.125-179.9375
            print(ii,jj,int(s[i][j:j+4])/100,file = f) #单位换成10^15
            #print("实际行和纬度",i+1,ii,"该行的第X个的经度",j_each+1,jj,int(s[i][j:j+4]))
    print(i)
f.close()