Figure 6.20

GEO-GRAPHIC: Possible causes of the current warming trend. Climate scientists do not believe that natural climate forcing factors, such as El Niño (described in Section 5.5) or the factors discussed in Section 6.2, have produced the warming trend of the last 100 years. The graphs show the departure from the average temperature (from 1951–1980 and defined as 0°C) caused by each of these factors.