Although direct measurements of atmospheric carbon dioxide have only been taken consistently since the 1950s, scientists have been able to retrieve data from the past 500,000 years. They have been able to do this by looking at

The correct answer is that scientist have developed different methods for studying earth's atmosphere and climate where they analyse a different elements of nature.

Explanation:

Scientists have over the years developed many scientific methods and theories by which they can retrieve data from 500000 years past and measure directly the amount of atmospheric carbon dioxide. They study different elements of the nature ice cores, tree rings as well as ocean and lake floor sediment to name a few. All of the above basic elements of nature help scientists to retrieve data from round 500000 years past.

it is a solid

explanation: