No, BUT THE ONLY REASON YOU KNOW it was an inland sea is due to geologic analysis. That same analysis is integrated into PALEOCLIMATOLOGY which is the study of ancient climates and ancient climate change. That's how we know how the NATURAL forcings work. And it is largely how we know that the CURRENT warming we see cannot be explained solely by natural forcings.
(Now, in reality, since I don't know where you live I'm going to take a guess and say that the reason you are no longer an inland sea, or what is often called an epieric sea is probably more related to plate tectonics and/or subsidence, or in the case of where I'm from (the midwest) filling in by erosion of the Appalachian Mountains. So it may have had exactly zero to do with climate change in the past.)