People in the Mountains - Mountain Geography: Physical and Human Dimensions - page 500

ther adaptations, such as seasonal cropping of potatoes, carrots, and other hardy veget-
ables and development of winter tourism, are occurring.
As discussed in Chapter 3, some altitudinal and seasonal temperature variations in
the central Andes, East African, and other equatorial mountains are similar to those dis-
cussed above; others are distinctly different. Quito in Ecuador (2,850 m), for example,
has an average annual temperature of 15°C and a January-July seasonal variation of
only 0.6°C. In contrast, diurnal temperature fluctuations often exceed 10°C. Subfreez-
ing temperatures are rare below 2,800 m, but significant diurnal fluctuations, including
freezing and thawing, are common in the high Andes, where they are of great ecolo-
gical and agricultural relevance. For example, permanent settlements are possible in
the highest ecozones of the Puna, at altitudes exceeding 4,000 m, where agricultural
activity consists of herding sheep, llamas, and alpacas, supplemented by some field cul-
tivation of tuber crops and cold-resistant grains (e.g., quinoa). Regular night freezing
makes agriculture and food storage difficult, but crop selection and preservation adapt-
ations, such as the making of chuno (see Chapter 11), have sustained large populations
and complex civilizations.
Mountain people and their activities have been greatly affected by temperature vari-
ations over time as part of shorter- or longer-term climate changes. While higher tem-
peratures in medieval times allowed settlement, specific agricultural land uses and min-
ing activities at higher altitudes, the subsequent Little Ice Age from the seventeenth to
the late nineteenth century impaired human activities at higher elevations and restric-
ted their altitudinal reach. Today, many mountain dwellers are concerned about the cur-
rent warming trend, the melting of glaciers, and the related threat to a reliable water
supply in some arid and semiarid regions (e.g., Orlove et al. 2008). In the Alps, winter
resorts at altitudes below approximately 1,000 m fear for the future of a sufficiently long
and reliable ski season and the greater economic and environmental costs of artificial
snowmaking (Steiger and Mayer 2008).