Question

What is the Suess Effect and why is it important?

Answer 1

Carbon molecule has 6 protons, 6 electrons and 6 neutrons. Isotopes of carbons differ in neutron number. Carbon has about 9 isotopes out of which 12C, 13C and 14C are used in carbon dating. 12C contains 6 neutrons as ,13C contains 7 neutrons and 14C contains 8 neutrons, which is formed when a thermal neutron displaces on of the proton in 14N. Atmosphere majorly consists of 12C carbon and 1% of 13C and very trace amounts of 14C which is very important in estimating the age of fossils and this process is what is called radiocarbon dating or carbon dating. It is not a stable isotope and decays to 12N.

Normally the plants fix 14C by photosynthesis and incorporate it into their body and animals also have trace amounts of 14C as they survive by eating plants. So plants have 12C, trace amounts of 14C and less amount of 13C. But their ratio of 12C:14C is almost same as the atmospheric ration of the same. Once a living organism dies, it is depleted of 14C gradually and this helps in studying the age of the fossil by comparing it's ratio of 12C:14C to that of living organisms.

But when these fossil fuels are burnt, they emit Carbon which has the isotopes 12C and less13C and no 14C because of which the atmospheric distribution of 12C and 13C is disturbed and this dilutes the ratio of the isotopes in the atmosphere. This is called Suess effect.

It has a major impact on radiocarbon dating and skews the results of it as the comparison and estimation of the ratios of the isotopes cannot be accurate with the dilution of the ratios and increase in the atmosphere.It was documented since '70s and named Suess effect after an Austrian chemist Suess when he found it's effects n radiocarbon dating.