Answer:
Prior to the industrial revolution our planets atmosphere was still untainted by human made pollutants.
Scientists thought that until recently. When bubbles were trapped in Greenlands riverbed, that we began emitting greenhouse gases at least 2,000 years ago.
Explanation:
Scientists often guage past climate and atmospheric conditions from pristine ancient ice samples.
The new research was based on 1,600 foot-long ice cores extracted from greenland's 1.5 mile thick ice sheet, which is made up of thick massive accumulatd layers of snow.
- The gas methane in ice occurs in the atmosphere in low concentrations.
- It is now a greenhouse gas implicated in climate change because of emissions in landfills, large scale cattle-ranching, natural gas pipeline
leaks, and land-clearing fires.
