Ed-M, the map's pretty simple. The Republic of New England and the Maritimes consists of the New England states from Massachusetts north, and the Maritime provinces that are now part of Canada. Quebec is Quebec. East Canada is Ontario, Manitoba, and points north. The Lakeland Republic is Ohio, West Virginia except for the western panhandle, Indiana, Kentucky, Illinois, Michigan, and Wisconsin. The Confederate States of America is the old Confederacy of 1861 minus Texas, and plus the southeastern quarter or so of Missouri. The Missouri Republic is the rest of Missouri, Kansas, Nebraska, Iowa, Minnesota, and the Dakotas, along with all of Wyoming and Montana east of the Continental Divide and the northeastern third or so of Colorado. The Republic of Texas is Texas, Oklahoma, New Mexico, and part of southern Colorado. The Republic of Deseret is Utah, Idaho minus the panhandle, and the portions of Colorado and Wyoming west of the continental divide. Arizona and Nevada are abandoned territory, uninhabitable due to climate change. The Republic of California is California, and the Cascade Republic is Washington, Oregon, the Idaho panhandle, and the portion of Montana west of the continental divide. Oh, and there's the Kingdom of Hawai'i and the Republic of Alaska, if you want to include them. Sea level has gone up about six feet; New Orleans, Galveston, and the Florida Keys no longer exist, and the southern end of Florida has been heavily eroded by rising seas and massive hurricanes, so it's not the same shape as it is today. Got it?And so with that information, I created a map.
I got the Atlantic/Florida/Gulf Coasts drownings from this photo here. I went by that photo's 2 degree Celsius projected sea level rise which looks about right but I think is a gross underestimate for a 2 deg C tempreature rise. And at the current Carbon Dioxide Levels? It's going to be worse: higher temps and higher sea level rise.
I also tweaked SF Bay, the Puget Sound and Vancouver BC area, the Cook Inlet (Anchorage AK), the Yukon Delta and the MacKensie Delta to account for a 6-foot rise. Of course, the water that far up North might not rise being it's so close to Greenland and all.