Grid Statistics - 2° Latitude by 2° Longitude Cells

The one-degree grid cell contour maps in the preceding section could be considered 'noisy' and some of the detail in the original grid analysis could be related to the small grid-size itself. There is also the inherent limitation of using a grid based upon a fixed degree size in that the area of a grid cell changes as one moves from south to north. Effectively, this means that a storm count further north is more significant than the same count further south.

Example: 1° x 1° degree cells at different latitudes:

Cell 1, 14° N–16° N, 47,773 km²
Cell 2, 40° N–42° N, 37,323 km²
Ratio of areas = 47,773 / 37,323 = 1.28

A storm count of 10 in each cell actually represents an
effective count of 10 * 1.28 = 12.8 over the northern cell.

It was decided to reanalyze the data based upon a 2° x 2° grid and to add additional charts that attempt to address the issue of the changing cell areas over the grid extent. The 36 maps that follow attempt to provide a thorough review of this topic. The maps are arranged as shown below: