Climate

The climate of the Titicaca Basin is dominated by typical tropical wet-dry seasons. The majority of the precipitation is derived from warm air masses arriving from Amazonia, to the east. Located as it is between two major weather systems, the Atlantic-Amazonian and the Pacific, climate in the Titicaca Basin is highly variable, and ``[i]nterpretation of long-term climate averages must be tempered with the understanding that interannual variability is expressed by standard deviations ranging from 20 to 70 percent of the average means'' ([Binford and Kolata 1996]: 30).

The average annual precipitation at the town of Guaqui, which is probably very similar to that of the Taraco Peninsula, is 581 mm ([Binford and Kolata 1996]: 31), most of which falls between December and March (Figure 2.3; for more detail see [Binford and Kolata 1996]: 31-32). Average temperature in the dry season season is between $-14^{\circ }$C and $22^{\circ }$C, and in the rainy season between $-5^{\circ }$C and $23^{\circ }$C ([Albarracín-Jordan 1996a]: 9). Therefore, frost can occur at any time of year, though it is more likely in the dry season, and especially in June and July when the minimum nighttime temperature averages $0^{\circ }$C or less (Figure 2.3). This is one of the principal factors which makes the Titicaca Basin a risky environment for agriculture. Frost is more likely in certain locations such as the bottom of quebradas or on the lake plain. These locations are often avoided, with gentle slopes being the preferred agricultural locations.

Figure 2.3: Precipitation, temperature, and agricultural labor by month