Natural changes in cold Andean and Patagonian environments, the problem of global warming and anthropical as well as cultural changes in periglacial, para-periglacial and cold desertical landscape environments.

DARIO TROMBOTTO LIAUDAT

Santiago de Chile

Congreso; Regional Geographic Conference IGU 2011; 2011

International Geographical Union (IGU)

The periglacial Andean regions undergo remarkable changes or processes that can be associated to global warming. These processes generally affect the geomorphology of periglacial environments with permafrost or not and of glaciated cold environments. They need to be monitored and analysed because there is very little documentation and follow-up concerning this topic and its implications for the hydrological cycle of the Andes for example. One example of the physical geography is a temperature rise.  The rise of the annual temperature distribution is to be seen year after year in the reactivation of thermokarst on the surface of lithoglaciers and covered glaciers, reflecting an unstable equilibrium between the buffer zone of the Andean cryolithosphere and the present climate. Another phenomenon to be observed in this landscape are mudflows triggered on mountain slopes in higher altitudes which flow downwards. These mudflows are often very hazardous.  The expansion of human settlements in the Andean piedmont towards higher altitudes also ignores the function of the piedmont as water recharge which is directly linked with less steep areas parallel to the mountains. The growing settlement also forgets the fact that mudflows are received and stopped by the piedmont. This human expansion into the mountains confronts society as a whole with a great, immanent social cost. Natural changes area also observed in extra Andean mountain regions such as Payenia (36º30´ SL). Changes in the cryospheric system of this region have a direct impact on livelihoods and activities of goatherds and are closely linked to natural water basins. This environment at lower altitudes (para-periglacial environment) is already suffering great changes caused by the demographic growth and the cultural changes we are witnessing in modern society with its high consumption of natural resources, unlimited tourism and a complete lack of territorial planning at the same time. This change is taking place much faster than any control system could ever register, even if there was such a system. At the same time those changes considered to be climatic refer to short periods of time and are correlated to conflicting markets, production and commerce which react more sensibly to stress than in past times.  There is an important change in the transitional semi-desertical landscape and the environment of the Patagonian valleys (Chubut) which receive migrants from other provinces or abroad, weakening and disintegrating indigenous and early Welsh communities who have been pioneers in the successful management of ecosystems. These changes reflect socio-economic problems in original environments and they are enhanced by transformations in production, chaotic growth and the absence of territorial planning in other regions which undergo natural changes. Policy on the population growth however does not take into account possible future climatic variations of the Patagonian Andes.