difference in time scales between natural and social phenomena: the causes of environmental change that stretch back in time may be dealt with socially over a comparatively brief period. Although at all times environmental influences have extended beyond particular geographic regions and cultures, during the 20th and early 21st centuries anthropogenic environmental change has assumed global proportions, most prominently with climate change but also as a result of settlement, the spread of disease and the globalization of world trade. History The questions of environmental history date back to antiquity, including Hippocrates, the father of medicine, who asserted that different cultures and human temperaments could be related to the surroundings in which peoples lived in Airs, Waters, Places. Scholars as varied as Ibn Khaldun and Montesquieu found climate to be a key determinant of human behavior. During the Enlightenment, there was a rising awareness of the environment and scientists addressed themes of sustainability via natural history and medicine. However, the origins of the subject in its present form are generally traced to the 20th century. In 1929 a group of French historians founded the journal Annales, in many ways a forerunner of modern environmental history since it took as its subject matter the reciprocal global influences of the environment and human society. The idea of the impact of the physical environment on civilizations was espoused by this Annales School to describe the long term developments that shape human history by focusing away from political and intellectual history, toward agriculture, demography, and geography. Emmanuel Le Roy Ladurie, a pupil of the Annales School, was the first to really embrace, in the 1950s, environmental history in a more contemporary form. One of the most influential members of the Annales School was Lucien Febvre (1878–1956), whose 1922 book A Geographical Introduction to History is now a classic in the field. The most influential empirical and theoretical work in the subject has been done in the United States where teaching programs first emerged and a generation of trained environmental historians is now active. In the United States environmental history as an independent field of study emerged in the general cultural reassessment and reform of the 1960s and 1970s along with environmentalism, "conservation history", and a gathering awareness of the global scale of some environmental issues. This was in large part a reaction to the way nature was represented in history at the time, which “portrayed