ALTERATIONS TO PERMAFROST ENVIRONMENTS INDUCED BY CLIMATE CHANGE Alteraciones a los Entornos de Permafrost Inducidas por el Cambio Climático

• Main Authors: Kai Whiting, A L Khalifa, Khaili, Luis Gabriel Carmona
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: permafrost; Thermokarst; Tundra
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.1069.7879; http://bibliotecadigital.univalle.edu.co/bitstream/10893/8273/1/alteraciones%20a%20los%20entornos.pdf

Abstract Permafrost environments currently cover approximately twenty-five percent of the Northern Hemisphere. However current empirical and theoretical evidence indicates that much of the existing permafrost is in thermal imbalance to the warming that has occurred over the last 150 years. Long-term increases of temperature in the polar regions has already led to a thickening of the active layer and the gaseous release of the once sequestered carbon and methane tundra stores; an event which is likely to amplify the changes foreseen and experienced in natural and human environments. Permafrost degradation has resulted in the complete restructuring of ecosystems and geomorphological and hydrological patterns and processes. Such changes have led to extensive thawing, removal of discontinuous permafrost and the growth of thermokarst. Collectively, all these climatic-induced alterations in the structure of permafrost environments has had a detrimental effect on wildlife populations, human settlement and infrastructure. The former has seen a transition from terrestrial to aquatic ecosystems whilst damage to the latter has led to some areas being officially classed as natural hazard zones. Therefore research and corresponding action must be undertaken at those locations where sequestered carbon is being released in sufficient quantities to be of concern to the wellbeing of the entire planet. Keywords: Active layer, Global Warming, Polar Regions, Thermokarst. Resumen Los entornos de permafrost actualmente cubren aproximadamente el veinticinco por ciento del hemisferio norte. Sin embargo, la evidencia empírica y teórica actual indica que gran parte del permafrost existente está en desequilibrio térmico por el calentamiento que se ha producido en los últimos 150 años. Los aumentos de la temperatura a largo plazo en las regiones polares ya han dado lugar a un engrosamiento de la capa activa y a la liberación gaseosa de los depósitos de carbono y el metano alguna vez secuestrados en la tundra; un evento que es probable que ...