If you change a single base in a codon then
1.the codon could code for nucleic acids instead of amino acids
2.the codon could code for a different amino acid
3.the dna strand containing the codon could fall apart
4.the codon could automatically repair itself

Global warming will produce rising sea levels partly due to melting ice caps but also due to the expansion of water as average ocean temperatures rise. to get some idea of the size of this effect, calculate the change in length (in m) of a column of water 1.45 km high for a temperature increase of 1.12°c. assume the column is not free to expand sideways. as a model of the ocean, that is a reasonable approximation, as only parts of the ocean very close to