Definite change since the formation of the Earth [Reply to Kleber, A. Comment on “Koutsoyiannis, D. Net isotopic signature of atmospheric CO2 sources and sinks: No change since the Little Ice Age. Sci 2024, 6, 17”]

Careful inspection of the title and graphical abstract of the original paper would have eased the concerns expressed by Kleber in his Comment. The title of the original paper clarifies that it examines the period since the Little Ice Age, and during this period no change was found in the net isotopic signature of atmospheric CO2 sources and sinks. Obviously, this result should not and cannot be extended to longer periods such as the last glacial cycle, brought up by the Commentator, or to even longer periods. Definitely, there has been change ever since the formation of the Earth, and there always will be in the future. And even the last glacial cycle alone helps us to see this change.