You do realize that whether or not you believe in anthropogenic global warming, sea level rise isn’t a theory, it’s an established fact? Sea levels rose ~20cm (8") over the last century, and the rate of rise has been increasing – nearly twice as fast in the last 20 years as the average rate over the preceding 80 years. If the rise continues at the current rate, the rise over the 21st century will be around 35cm. If the rise continues to accelerate at the current rate, the rise is likely to be closer to 1m. If, as is expected, the Greenland and West Antarctic Ice Sheets continue to melt at their current rate, the rise will pass a tipping point in as little as one to two decades, and accelerate rapidly, as the sea level rise will lead to sea levels being above the edge of the Antarctic continent – the ocean will surge inland (because ice floats), since due to the immense mass of ice, inland is already well below sea level. If that happens, the sea will float a much of the WAIS, meaning that immense mass of ice, even if it doesn’t melt, will cause a rapid rise of 3-5 metres in sea levels. Even the low end of all these projections will have significant impact on coastal areas in much of the globe. The high end could put much of the world’s most populous areas underwater, or much more vulnerable to storms and tides.