A European pattern climatology 1766–2000 |
| |
| Authors: | Carlo Casty Christoph C Raible Thomas F Stocker Heinz Wanner Jürg Luterbacher |
| |
| Institution: | (1) Climate and Environmental Physics, Physics Institute, University of Bern, Bern, Switzerland;(2) Climatology and Meteorology, Institute of Geography, University of Bern, Bern, Switzerland;(3) NCCR Climate, University of Bern, Bern, Switzerland |
| |
| Abstract: | Using monthly independently reconstructed gridded European fields for the 500 hPa geopotential height, temperature, and precipitation
covering the last 235 years we investigate the temporal and spatial evolution of these key climate variables and assess the
leading combined patterns of climate variability. Seasonal European temperatures show a positive trend mainly over the last
40 years with absolute highest values since 1766. Precipitation indicates no clear trend. Spatial correlation technique reveals
that winter, spring, and autumn covariability between European temperature and precipitation is mainly influenced by advective
processes, whereas during summer convection plays the dominant role. Empirical Orthogonal Function analysis is applied to
the combined fields of pressure, temperature, and precipitation. The dominant patterns of climate variability for winter,
spring, and autumn resemble the North Atlantic Oscillation and show a distinct positive trend during the past 40 years for
winter and spring. A positive trend is also detected for summer pattern 2, which reflects an increased influence of the Azores
High towards central Europe and the Mediterranean coinciding with warm and dry conditions. The question to which extent these
recent trends in European climate patterns can be explained by internal variability or are a result of radiative forcing is
answered using cross wavelets on an annual basis. Natural radiative forcing (solar and volcanic) has no imprint on annual
European climate patterns. Connections to CO2 forcing are only detected at the margins of the wavelets where edge effects are apparent and hence one has to be cautious
in a further interpretation.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. |
| |
| Keywords: | Independent climate field reconstructions Europe Climate patterns Combined EOFs |
| 本文献已被 SpringerLink 等数据库收录！ |
|
