EVIDENCE FOR ELEVATIONAL-DEPENDENT WARMING (EDW) AND THE UNDERLYING MECHANISMS DRIVING EDW

Abstract:

There is increasing evidence that the rate of warming is amplified with elevation, so that high mountain environments are experiencing more rapid changes in temperature than at lower elevations. This “elevational-dependent warming” (EDW) has important implications for the mass balance of high altitude glaciers and associated runoff, as well as for species that reside in restricted altitudinal zones within a mountain range. Temperature change at the earth’s surface is primarily a response to the energy balance, and therefore factors which preferentially increase the net flux of energy to the surface, along an elevation gradient would lead to enhanced warming, as a function of elevation. This points to changes in albedo (primarily snow cover), clouds, water vapor and aerosols as likely candidates that drive EDW. However, detecting and attributing the causes of EDW is confounded by data limitations and the difficulties of modeling processes in complex terrain. There is a danger that we may not be monitoring some of the regions of the globe that are warming the most, and we need a strategy for future research that will reduce current uncertainties and ensure that the changes taking place in high elevation, remote regions of the planet are properly monitored.