Grandpa's Winter Data
By: Aida , Preston, and Job
Info . 💁
1. The 20th Century has been like no other.
2. Carbon dioxide concentrations in the atmosphere have risen from 290 parts per million (ppm) to 369 ppm.
3. Many climate researchers and policy makers are concerned that increased in population and rising standards of living will lead to ever higher levels of carbon dioxide and other greenhouse gases.
4. Droughts have also caused severe problems in the United States during the 20th Century.