Future climate change

The climatic effects of rising CO₂ levels will become increasingly significantin the future. Consumption of estimated reserves of fossil fuels in the next two or three centuries will add far more CO₂ to the atmosphere than has been emitted to date unless ambitious conservation efforts or technological innovations reduce the influx. Atmospheric CO₂ concentrations will increase to levels at least twice and possibly four times the highest amounts measured in the last 800,000 years spanned by ice-core records. This warming will overwhelm natural variations in climate and cause climatic and environmental changes unprecedented in human experience. Atmospheric CO₂ levels will eventually decrease as the ocean slowly absorbs much of the excess carbon, but this process will acidify the oceans. After the main pulse of fossil-fuel emissions has passed, atmospheric CO₂ values will decrease back toward preindustrial levels, but enough CO₂ willremain in the atmosphere to prevent future glaciations for tens of thousands of years.