CO2 and Temperature
Until modern industrial times, the earth’s surface temperature approximately followed atmospheric CO2 levels. Today, this is no longer the case. Surface temperatures are lagging behind CO2 increases (Figure A). This sudden and dramatic increase in atmospheric CO2 levels cannot be attributed to natural phenomena, such as solar and volcanic activity, and is therefore a cause for serious concern. There is currently a 0.7°C (approx.) rise in temperatures above pre-industrial levels, and if surface temperatures continue to follow CO2 emissions, temperatures will likely continue to rise (Figure B). Assuming a business-as-usual scenario, scientists’ predictions indicate a roughly 50% probability that global surface temperatures will rise relative to increasing CO2 levels and we will reach warming of 2°C above pre-industrial levels by 2050, and 3 degrees by 2100 (Figure C). If we do not make the necessary CO2 and other greenhouse gas reductions quickly, this warmer planet will be the world our children and grandchildren will inherit. Dr. James Hansen has stated: “Warming of more than 1 degree Celsius above today’s level
will make the Earth warmer than it has been in a million years.
The Earth’s history suggests that with warming of 2-3°C the new equilibrium sea level will include not only most of the ice from Greenland and West Antarctica, but a portion of East Antarctica, raising sea level of the order of 25 meters (80 feet)... real world data suggest substantial ice sheet and sea level change in centuries, not millennia. Action must be prompt, otherwise CO2-producing infrastructure that may be built within a decade will make it impractical to keep further global warming under 1°C.” Dr. Hansen has set a timeline of ten years. We have ten years to make the changes necessary to keep warming from reaching 2°C above pre-industrial levels. |
 Temperature and CO2 Levels (Figure A)
 Temperature Anomalies, 1890-1999 (Figure B) Source: www.whrc.org/  Earth's Surface Temperature (Figure C) |