Land‐use change and climate

Human activities in Australia and world‐wide cause, or contribute to, desertification, deforestation, salinization and soil erosion, and also to reforestation, irrigation and landscape ‘management’. Human‐induced land‐use changes impact on the Earth's climate both locally and on a larger scale, right up to disturbance of the general circulation and hence the global climate. People have become a major environmental agent acting on the future climate through land‐use change, particularly deforestation (and reforestation), desertification (which often includes overgrazing and excessive exploitation of vegetation), agricultural expansion, and soil erosion and degradation. The largest impact of land‐use change on the future climate seems likely to be as a result of enhanced greenhouse gas emissions. At the same time, rapidly increasing populations, especially in the tropics, demand additional food, water for drinking and cleaning, and materials for the construction of shelters—all of which depend upon sustaining a reasonable climate. Climate and human land‐use requirements are linked, but the closeness of that link varies from intimate dependency to callous disdain. In this paper, the impacts of human‐induced land‐use changes on future climate are explored in the context of the projections of global climate models.