A new high resolution absolute temperature grid for the Greater Alpine Region back to 1780

Abstract

This study presents a new gridded dataset providing absolute monthly mean temperatures across the Greater Alpine Region (GAR) of Europe at a spatial resolution of 5 arcmin (6 × 9 km in the region) from 1780 to 2008. The starting point was a set of long-term homogenized station time series. To assure the quality of the analyses back in time, when the station density decreases, missing measurements were reconstructed by an Empirical Orthogonal Function analysis that can deal with gappy data. It is shown that the reconstructed values comprise similar statistical features to the observations and that the method produces no breaks between the reconstructions and the observations. The compound anomaly dataset was then interpolated separately for two different altitude ranges to preserve anomaly gradients between high and low elevations. This allowed for the derivation of individual anomalies at each grid point in GAR. Finally, these smooth anomalies were blended with the highly resolved monthly mean absolute temperature fields, provided by a project of the European Climate Support Network. The added value of this new high resolution and long-term temperature dataset is shown and discussed using the examples of the height of the 0°C altitude and vertical lapse rates. For the first time, these and other features are now available for more than two centuries in a topographically complex region like GAR.

Development of a longterm dataset of solid/liquid precipitation

“…To provide a comparable spatial resolution of the data over the whole period missing parts of the station-mode series were reconstructed by an EOF-method. For details see Chimani et al (2010). Moreover a regional high resolution longterm absolute monthly precipitation dataset was used to generate information not only about the percentage of solid precipitation over the last 200 years but also for the solid/liquid totals in mm.…”

“…The derived method is applied on the existing high-resolution longterm grids of these two basic climate parameters (Efthymiadis et al, 2006;Chimani et al, 2010) in the "Greater Alpine Region" (henceforth GAR), which…”

Among‐tree variability and feedback effects result in different growth responses to climate change at the upper treeline in the Swiss Alps

“…For the analysis of climate–tree growth relationships, gridded HISTALP monthly mean surface temperature (spatial resolution 5 arc minutes) was used (Chimani, Matulla, Böhm, & Hofstätter, ). To ensure correct representation of treeline temperature conditions in the HISTALP data, a total of 72 (eight per plot) temperature loggers (iButton DS1922L, Maxim Integrated) were installed, which recorded hourly 2 m air temperature between May 2014 and November 2015.…”

“…Long‐term trends of monthly mean temperature at each study site were quantified using time series derived from the nearest grid point of the HISTALP monthly mean surface temperature dataset (Chimani et al., ). Locally weighted smoothing splines of monthly temperature anomalies with regard to the 30‐year mean from 1971 to 2000 were calculated.…”

Climate change impacts on the Alpine ecosystem: an overview with focus on the soil

“…Mountain climates are governed by four major factors, namely continentality, latitude, altitude and topography. Altitude is certainly the most distinguishing and fundamental characteristic of mountain climates (Chimani et al 2013; Supported by the Mendel University in Brno, Czech Republic, Grant No. IGA FFWT MENDELU 55/2013 Morán- Tejeda et al 2013), while topographic features play a key role in determining local climates, in particular due to slope, aspect and exposure of the surface to climatic elements (Beniston 2006;Liancourt et al 2013).…”