I want to create a map presenting the temporal changes in world sea water level for last 5 decades. Is there any source from where I can get the GIS Data?
You have this placed in 911 gis... which is about emergency services, not that you are having an emergency getting the data.
Perhaps you might want to move it to ArcGIS Open Data community or maybe Mapping and Charting or even ArcGIS Online if it is for online use.
Retrieving data ...