我正在下载用于等高线绘图和分析的 netCDF 数据集,但无法完全正确地进行数据投影。该文件说它是 Lambert Conformal Projection 并提供 lat/lon min/max:
geospatial_lat_min: 17.5812268306
geospatial_lat_max: 55.5349606426
geospatial_lon_min: -140.027321405
geospatial_lon_max: -57.2098720419
但是,x 和 y 数据点有点混乱(下面显示的 y 供参考):
print data.variables['y'][:]
[ -4.26348724e+02 -4.06030731e+02 -3.85712738e+02 -3.65394714e+02
-3.45076721e+02 -3.24758728e+02 -3.04440735e+02 -2.84122711e+02
-2.63804718e+02 -2.43486725e+02 -2.23168716e+02 -2.02850723e+02
-1.82532715e+02 -1.62214722e+02 -1.41896713e+02 -1.21578720e+02
-1.01260719e+02 -8.09427185e+01 -6.06247177e+01 -4.03067169e+01
-1.99887161e+01 3.29285234e-01 2.06472855e+01 4.09652863e+01
6.12832870e+01 8.16012878e+01 1.01919289e+02 1.22237289e+02
1.42555298e+02 1.62873291e+02 1.83191299e+02 2.03509293e+02
2.23827301e+02 2.44145294e+02 2.64463287e+02 2.84781311e+02
3.05099304e+02 3.25417297e+02 3.45735291e+02 3.66053314e+02
3.86371307e+02 4.06689301e+02 4.27007294e+02 4.47325317e+02
4.67643311e+02 4.87961304e+02 5.08279297e+02 5.28597290e+02
5.48915283e+02 5.69233337e+02 5.89551331e+02 6.09869324e+02
6.30187317e+02 6.50505310e+02 6.70823303e+02 6.91141296e+02
7.11459290e+02 7.31777344e+02 7.52095337e+02 7.72413330e+02
7.92731323e+02 8.13049316e+02 8.33367310e+02 8.53685303e+02
8.74003296e+02 8.94321350e+02 9.14639343e+02 9.34957336e+02
9.55275330e+02 9.75593323e+02 9.95911316e+02 1.01622931e+03
1.03654736e+03 1.05686536e+03 1.07718335e+03 1.09750134e+03
1.11781934e+03 1.13813733e+03 1.15845532e+03 1.17877332e+03
1.19909131e+03 1.21940930e+03 1.23972729e+03 1.26004529e+03
1.28036328e+03 1.30068140e+03 1.32099939e+03 1.34131738e+03
1.36163538e+03 1.38195337e+03 1.40227136e+03 1.42258936e+03
1.44290735e+03 1.46322534e+03 1.48354333e+03 1.50386133e+03
1.52417932e+03 1.54449731e+03 1.56481531e+03 1.58513330e+03
1.60545129e+03 1.62576941e+03 1.64608740e+03 1.66640540e+03
1.68672339e+03 1.70704138e+03 1.72735938e+03 1.74767737e+03
1.76799536e+03 1.78831335e+03 1.80863135e+03 1.82894934e+03
1.84926733e+03 1.86958533e+03 1.88990332e+03 1.91022131e+03
1.93053931e+03 1.95085742e+03 1.97117542e+03 1.99149341e+03
2.01181140e+03 2.03212939e+03 2.05244727e+03 2.07276538e+03
2.09308325e+03 2.11340137e+03 2.13371948e+03 2.15403735e+03
2.17435547e+03 2.19467334e+03 2.21499146e+03 2.23530933e+03
2.25562744e+03 2.27594531e+03 2.29626343e+03 2.31658130e+03
2.33689941e+03 2.35721729e+03 2.37753540e+03 2.39785327e+03
2.41817139e+03 2.43848950e+03 2.45880737e+03 2.47912549e+03
2.49944336e+03 2.51976147e+03 2.54007935e+03 2.56039746e+03
2.58071533e+03 2.60103345e+03 2.62135132e+03 2.64166943e+03
2.66198730e+03 2.68230542e+03 2.70262329e+03 2.72294141e+03
2.74325928e+03 2.76357739e+03 2.78389551e+03 2.80421338e+03
2.82453149e+03 2.84484937e+03 2.86516748e+03 2.88548535e+03
2.90580347e+03 2.92612134e+03 2.94643945e+03 2.96675732e+03
2.98707544e+03 3.00739331e+03 3.02771143e+03 3.04802930e+03
3.06834741e+03 3.08866553e+03 3.10898340e+03 3.12930151e+03
3.14961938e+03 3.16993750e+03 3.19025537e+03 3.21057349e+03
3.23089136e+03 3.25120947e+03 3.27152734e+03 3.29184546e+03
3.31216333e+03 3.33248145e+03 3.35279932e+03 3.37311743e+03
3.39343530e+03 3.41375342e+03 3.43407153e+03 3.45438940e+03
3.47470752e+03 3.49502539e+03 3.51534351e+03 3.53566138e+03
3.55597949e+03 3.57629736e+03 3.59661548e+03 3.61693335e+03
3.63725146e+03 3.65756934e+03 3.67788745e+03 3.69820532e+03
3.71852344e+03 3.73884155e+03 3.75915942e+03 3.77947754e+03
3.79979541e+03 3.82011353e+03 3.84043140e+03 3.86074951e+03
3.88106738e+03 3.90138550e+03 3.92170337e+03 3.94202148e+03
3.96233936e+03]
编辑:x/y 投影坐标定义为以公里为单位。
我有 x 和 y 长度(分别为 301 和 217),感觉我可以手动定义 lat 和 lon 值或使用 PyProj 转换投影。但是,我有点迷失从哪里开始。
我最初的想法是使用最小纬度和经度以及网格点之间的平均差异:
for i in range(0,len(lat_vals)):
lat_vals[i] = 16.28100013732909+0.18297297297*i
for j in range(0,len(lon_vals)):
lon_vals[j] = -139.9440104734173+0.27634406361*j
但是,那是在我记得经度变化不会与纬度保持一致之前。
谢谢你的帮助!