A climatonomic study of the energy and moisture fluxes of the Amazonas basin with considerations of deforestation effects / Luiz Carlos B. Molion.

Tese (Ph.D.) - University of Wisconsin, 1975

Annual precipitation averages about 2400 mm in the Amazonas Basin of which 44 percent runs off according to hydrological estimates by Oltman and others. We evaluated advection from aerological charts by Newell et al., assuming that tropospheric import of precipitable water must compensate river runoff . According to aerology the hydrological estimates appears too low by 15 to 20 percent. Independently, we tested evapotranspiration estimates from surface-energy budget calculations provided by Henning, who had employed the methods by Budyko, Altrecht and Penman, to 40 climate stations in the basin. Those data also suggest that Oltman underestimated runoff, i.e., overestimated evapotranspiration. In a new approach, we divided the region into six lorgitudinal sections of 550 km width and derived water and energy balances (for soil moisture and precipitable water) with models of evapo- and thermoclimatonomy. The results confirm that Oltman's hydrological estimate was too low, by about 20 percent in the central section and nearly 90 percent in the atlantic section. Climatonomical parameters lend themselves to speculations on possible effects of large-scale deforestation. Tentative calculations suggest that the primary effect is one of lowering of soil moisture levels and enhancing the contrast between dry and wet seasons.