Table 5. The eigenvector coefficients of a standardized principal component analysis of original climatic variables.
| No. | Climatic variable | Axis 1 | Axis 2 | Axis 3 | Axis 4 |
|---|---|---|---|---|---|
| V1 | Annual mean temperature | 0.268549 | −0.30154 | −0.04182 | −0.06167 |
| V2 | Mean diurnal range | 0.154837 | −0.40671 | 0.153434 | −0.0833 |
| V3 | Isothermality | 0.296945 | −0.19697 | −0.16491 | −0.0661 |
| V4 | Temperature seasonality | 0.285549 | 0.178237 | 0.228065 | 0.026596 |
| V5 | Maximum temperature of the warmest month | 0.27084 | 0.077764 | 0.233843 | 0.266797 |
| V6 | Minimum temperature of the coldest month | 0.22525 | 0.235566 | 0.235308 | −0.25582 |
| V7 | Temperature annual range | −0.02231 | −0.28657 | −0.05584 | 0.519083 |
| V8 | Mean temperature of the wettest quarter | 0.268126 | 0.122484 | 0.232199 | 0.2296 |
| V9 | Mean temperature of the driest quarter | 0.2369 | 0.228993 | 0.225927 | −0.25839 |
| V10 | Mean temperature of the warmest quarter | 0.16399 | 0.029729 | 0.409481 | 0.267514 |
| V11 | Mean temperature of the coldest quarter | 0.264259 | 0.217343 | 0.02297 | −0.1566 |
| V12 | Annual precipitation | −0.22286 | −0.1774 | 0.317968 | −0.22584 |
| V13 | Precipitation of the wettest month | −0.10389 | −0.18329 | 0.143856 | −0.44201 |
| V14 | Precipitation of the driest month | −0.26818 | −0.03707 | 0.324793 | 0.041671 |
| V15 | Precipitation seasonality | 0.065615 | −0.42041 | 0.230196 | −0.16373 |
| V16 | Precipitation of the wettest quarter | 0.298626 | −0.16991 | −0.19483 | −0.05618 |
| V17 | Precipitation of the driest quarter | −0.26579 | −0.07492 | 0.334569 | −0.03937 |
| V18 | Precipitation of the warmest quarter | 0.139045 | −0.33209 | 0.183675 | 0.184543 |
| V19 | Precipitation of the coldest quarter | 0.262728 | −0.161 | −0.21275 | −0.22105 |
Note: The eigenvalues of the first four axes are: axis 1 = 0.4453, axis 2 = 0.2112, axis 3 = 0.1651, and axis 4 = 0.0854 (sum = 90.73% of total variance explained).