The New Zealand curve is representative for the Southern Hemisphere, the Austrian curve is representative for the Northern Hemisphere. This makes it possible to tell the age of substances that contain carbon. Dates obtained are usually written as before present ('present' is 1950).
Atmospheric nuclear weapon tests almost doubled the concentration of Radiocarbon dating, also known as the C14 dating method, is a way of telling how old an object is. Plants take up atmospheric carbon dioxide by photosynthesis, and are eaten by animals, so every living thing is constantly exchanging carbon-14 with its environment as long as it lives. In 1958 Hessel de Vries showed that the concentration of carbon-14 in the atmosphere varies with time and locality.
The half-lives of several radioactive isotopes are known and are used often to figure out the age of newly found fossils.
Different isotopes have different half-lives and sometimes more than one present isotope can be used to get an even more specific age of a fossil.
Atoms of carbon-12 have 6 neutrons, while atoms of carbon-14 contain 8 neutrons.
A neutral atom would have the same number of protons and electrons, so a neutral atom of carbon-12 or carbon-14 would have 6 electrons.
The number given after the atom name (carbon) indicates the number of protons plus neutrons in an atom or ion.
Atoms of both isotopes of carbon contain 6 protons.
Carbon-13 has 6 protons, just like other carbon isotopes, but it has 7 neutrons. Although 15 isotopes of carbon are known, the natural form of the element consists of a mixture of only three of them: carbon-12, carbon-13, and carbon-14. Measuring the difference in the radio between carbon-12 and carbon-14 is useful for dating the age of organic matter since a living organism is exchanging carbon and maintaining a certain ratio of isotopes.
You would need to have access to scientific instruments at this point that could measure the amount of radioactivity in the sample, so off to the lab we go!
After you prepare your sample and put it into the machine, your readout says you have approximately 75% Nitrogen-14 and 25% Carbon-14.
Now it is time to put those math skills to good use.
At one half-life, you would have approximately 50% Carbon-14 and 50% Nitrogen-14.
As radioactive isotopes of elements decay, they lose their radioactivity and become a brand new element known as a daughter isotope.