I am working on the distribution of marine invertebrates in the Indo-Pacific, and using ArcGIS 8.3. I want to be able to measure the area of the distribution of several species to compare those with a wide distribution to those with restricted distribution. I am looking for an equal area map projection that is optimized for the tropical Indo-Pacific (if there is something like that). In ArcMap there are many different projections available, including some equal area ones, but they don't produce the exact same results. The one that I found most useful, thus far, is called World Cylindrical Equal Area (in ArcGIS).
Can anyone recommend an equal area map projection suitable for the tropical Indo-Pacific area?