The effect of overgrazing on historical temperature trends

Twentieth century temperature records for a latitudinal band extending from 10°N to 50°N are stratified using a recent UNEP map showing areas affected by overgrazing. Linear trend analysis shows that the overgrazed areas have warmed at a rate of 0.0057 K year^-1 while land areas in the latitudinal band not impacted by overgrazing have warmed at a rate of 0.0035 K year^-1. The difference in temperature between the two groups has increased at a statistically significant rate over the 1901-1990 time period. While this temperature increase apparently associated with overgrazing may be important locally and regionally, the impact of overgrazing probably accounts for less than 1% of global warming over the same time period.