APPLICATION OF SEA ICE MAP PROJECTION TRANSFORMATION AND TILE CUTTING OVER THE ANTARCTIC OCEAN: APPLICATION OF SEA ICE MAP PROJECTION TRANSFORMATION AND TILE CUTTING OVER THE ANTARCTIC OCEAN

The distribution of sea ice over the Antarctic Ocean has a great impact on the navigation of icebreaker ships,and is an important subject of Antarctic research.Maps of sea ice over polar regions released by different international organizations are mostly stereographic projections,which cannot be directly overlaid on Google tile-maps.This paper presents an approach to transform the polar stereographic projection maps into Web Mercator projection maps,which are the most commonly used at present.The study included procedures to incise,number and store the map tiles with appropriate re-sampling algorithms,according to the given scale,and finally release and share the sea ice map tiles.The authors compared different re-sampling algorithms,and analyzed the advantages and weaknesses of Nearest Neighbor Re-sampling,Bilinear Interpolation,and Bicubic interpolation.Over the polar area,a Bilinear Interpolation algorithm is recommended to incise map tiles.Finally,sea ice tiles are overlaid on Google Maps in a "XUELONG Online" information platform,integrated with the real-time and historical locations of "XUE LONG" icebreaker.This approach contributes to the navigation of "XUE LONG" across the floating sea ice area.This study provides important information for the identification of icebreaker route selection over sea ice areas,both in Antarctica and the Arctic.