In what year did global warming start to be a problem?

Answer 1

In the 1700s people began burning fossil fuel in earnest. Before that they consumed a little bit of surface oil for lamps, or peat moss from bogs for heat. Some coal was burned in forges by iron workers, but not a huge amount. That coal and oil was still shipped by barge or ox cart.

So the problem of global warming was very small--earth could probably reabsorb all the CO2 emissions of the early industrial revolution, or nearly absorb them. We continued increasing our consumption of fossil fuels, doubling nearly every decade. What doubling consumption means is that, for example, in the ten years from 1910 to 1920 we burned more coal an oil than in all of human history prior to 1910. Again, from 1920 to 1930, we burned more coal and oil than in all of human history prior to 1920. From 1930 to 1940, we did it again, and again from 1940 to 1950, and again from 1950 to 1960, and so on, doubling consumption every decade for most of the 20th century.

Although Svante Arhenius established CO2 was a greenhouse gas by the late 19th century, climate scientists didn't really begin getting concerned about the issue until the 1950s, when we started measuring a steady rise in this gas. Earth's climate didn't begin responding in earnest to the changes until the 1980s.