Climate monitoring and heat and cold waves detection over France using a new spatialization of daily temperature extremes from 1947 to present

Abstract

Abstract. For many years real-time climate monitoring for temperature over France has been performed using a national index built by averaging the daily mean temperatures of constant subset of 30 stations with long-term series. In order to derive climate indices at finer scales, a spatialization of extreme daily temperatures (called ANASTASIA) had been produced on a 1 km regular grid using a regression-kriging method. The production covers 1947 to present period. Cross-validation shows low biases after the 1960s. The temporal homogeneity of the product is satisfying at the national scale from the 1970s. However, a high impact of the network density has been found and the use of a too coarse observation network deteriorates the analysis creating temporal heterogeneities. Finally, the ANASTASIA analysis has been used for real-time monitoring over France and detection of heat and cold wave episodes. The new products based on ANASTASIA are consistent with the current operational ones at national scale while bringing added values at local scales.

Evaluation of the Urban Heat Island of 12 Cities of France in a High-Resolution Regional Climate Model Simulation

“…The ANASTASIA (Analyse Spatiale des Températures de Surface avec Initialisation AURELHY) product is a gridded dataset of minimum (TN) and maximum (TX) daily temperature at 1-km horizontal resolution over Metropolitan France for the time period 1947-2016 (Besson et al, 2019). It uses a regression-kriging method (Hengl et al, 2007) with two sources of information: in situ observations of extreme daily TN and TX recorded by the weather stations of the operational Météo-France network and a monthly climatological field of daily TN and TX defined over the 1982-2010period (Cannelas et al, 2014.…”