Law
A degree of longitude shrinks with latitude
Euclidean distance over latitude and longitude is not distance at all.
How it behaves
One input on the horizontal axis, the others held fixed.
Data table
| Latitude (degrees) | km per degree |
|---|---|
| 0 | 111 |
| 1.11 | 111 |
| 2.23 | 111 |
| 3.34 | 111 |
| 4.45 | 111 |
| 5.56 | 110 |
| 6.67 | 110 |
| 7.79 | 110 |
| 8.9 | 110 |
| 10 | 109 |
| 11.1 | 109 |
| 12.2 | 108 |
| 13.3 | 108 |
| 14.5 | 107 |
| 15.6 | 107 |
| 16.7 | 106 |
| 17.8 | 106 |
| 18.9 | 105 |
| 20 | 104 |
| 21.1 | 104 |
| 22.3 | 103 |
| 23.4 | 102 |
| 24.5 | 101 |
| 25.6 | 100 |
| 26.7 | 99.2 |
| 27.8 | 98.2 |
| 28.9 | 97.2 |
| 30 | 96.1 |
| 31.1 | 95 |
| 32.3 | 93.9 |
| 33.4 | 92.7 |
| 34.5 | 91.5 |
| 35.6 | 90.3 |
| 36.7 | 89 |
| 37.8 | 87.7 |
| 38.9 | 86.3 |
| 40 | 85 |
| 41.2 | 83.6 |
| 42.3 | 82.1 |
| 43.4 | 80.7 |
| 44.5 | 79.2 |
| 45.6 | 77.6 |
| 46.7 | 76.1 |
| 47.8 | 74.5 |
| 49 | 72.9 |
| 50.1 | 71.3 |
| 51.2 | 69.6 |
| 52.3 | 67.9 |
| 53.4 | 66.2 |
| 54.5 | 64.4 |
| 55.6 | 62.7 |
| 56.7 | 60.9 |
| 57.9 | 59.1 |
| 59 | 57.2 |
| 60.1 | 55.4 |
| 61.2 | 53.5 |
| 62.3 | 51.6 |
| 63.4 | 49.7 |
| 64.5 | 47.7 |
| 65.6 | 45.8 |
| 66.8 | 43.8 |
| 67.9 | 41.8 |
| 69 | 39.8 |
| 70.1 | 37.8 |
| 71.2 | 35.8 |
| 72.3 | 33.7 |
| 73.4 | 31.7 |
| 74.5 | 29.6 |
| 75.7 | 27.5 |
| 76.8 | 25.4 |
| 77.9 | 23.3 |
| 79 | 21.2 |
| 80.1 | 19.1 |
| 81.2 | 17 |
| 82.3 | 14.8 |
| 83.4 | 12.7 |
| 84.5 | 10.5 |
| 85.7 | 8.4 |
| 86.8 | 6.24 |
| 87.9 | 4.09 |
| 89 | 1.94 |
Worked examples, recomputed
Every number the mechanisms quote for this relationship is recomputed from it, so none of them disagrees with it.
Where it appears
Each mechanism states it in its own names. The general symbol each name stands for is shown with it.
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