Title: Polar warming
Authors: Lola Gadea - University of Zaragoza (Spain) [presenting]
Jesus Gonzalo Munoz - Universidad Carlos III de Madrid (Spain)
Abstract: It is well known that what happens in the Arctic does not stay in the Arctic; but we need to know what is really happening there. We focus on the temperature in the Arctic circle. Applying a previous methodology, Polar Warming is defined as an increasing trend in certain distributional characteristics (moments, quantiles, etc) of polar temperatures, and not only on the average. We consider Arctic temperatures as a functional stochastic process from which we obtain distributional characteristics as time series objects. We apply our robust trend test to three different temperature databases that contain data from different stations in the Arctic: Climate Research Unit (CRU), Arctic Air Surface Temperature (SAT) and ERA-Interim reanalysis form the European Centre for Medium-Range Weather Forecast (ECMWF). The first two run from the ninetieth century to nowadays and the last one from 1979-2017. Preliminary analyses show that, with the first two, we obtain similar results to the ones obtained when analyzing the global temperature: (i) there is a clear positive trend in all the distributional characteristics of the temperature variable; (ii) the lower quantiles have a larger trend than the mean and upper quantiles and (iii) the variability is decreasing (variance has a negative trend, lower temperatures approach the median faster than the higher ones deviate from it).