Annual Bulletin on the Climate in WMO Region VI - Europe and Middle East
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The Network of European World Meteorological Deutscher Meteorological Services Organization Wetterdienst European Climate World Climate Data Department Climate Support Network and Monitoring Programme Monitoring Annual Bulletin on the Climate in WMO Region VI - Europe and Middle East - 2008 ISSN: 1438 – 7522 IInternet version: http://www.dwd.de/ravi/ http://www.dwd.de/ecsm http://www.gcmp.dwd.de/ Editor: Deutscher Wetterdienst Postfach 10 04 65, D – 63004 Offenbach am Main, Germany Phone: +49 69 8062 2938 Fax: +49 69 8062 3759 Responsible: Peter Bissolli E-mail: [email protected] Peer Hechler E-mail: [email protected] Technical assistance: Volker Zins E-mail: [email protected] Acknowledgements: Special thanks go to our colleagues G. Engel, T. Fuchs, G. Müller-Westermeier, H. Nitsche, J. Rapp and W. Thomas for their valuable comments and correc- tions. This text is an extended version of the publication “State of the climate in 2008”, Bull. Am. Met. Soc. Vol. 90, No. 7, July 2009, chapter “Regional climates”, sec- tion “Europe”. Annual Bulletin on the Climate in WMO Region VI - Europe and Middle East - 2008 The Bulletin is a summary of contributions from the following National Meteorological and Hydrological Services and was co-ordinated by the Deutscher Wetterdienst, Germany Albania Armenia Austria Azerbaijan Belarus Belgium Bosnia and Herzegovina Bulgaria Croatia Cyprus Czech Republic Denmark Estonia Finland France Germany Georgia Greece Hungary Iceland Ireland Israel Italy Jordan Kazakhstan Latvia Lebanon Lithuania Luxembourg The Former Yugoslav Republic of Macedonia Malta Moldova Montenegro Netherlands Norway Poland Portugal Romania Russia Serbia Slovakia Slovenia Spain Sweden Switzerland Turkey Ukraine United Kingdom List of Contents Foreword 5 Outstanding Events and Anomalies 6 Annual Survey 7 Seasonal Survey 28 Seasonal Maps 34 Monthly and Annual Tables 40 Monthly Surveys January 47 February 52 March 56 April 62 May 66 June 71 July 75 August 81 September 87 October 91 November 95 December 99 SPECIAL CONTRIBUTIONS: ECSN Activities Report 2008 104 The Ozone Layer over Central Europe in 2008 107 Annual Bulletin on the Climate in WMO Region VI - 2008 5 Foreword “Better climate information for a better future” – this is the theme of the WMO's World Climate Conference 3 in August/September 2009. Nowadays, a large amount of climate information is available, provided by National Meteorological and Hydrological Services and climate research centres: climate data from various data sources, climate analyses, assessments and predictions as well as impact studies. We all know their main message: climate change is still ongoing, even faster than in the past, and consequently, mitigation and adaptation to future climate continue to be important topics over the next years. Climate variability, however, shows a wide variety, both spatially and temporally. Policymakers, on their part, need to know details of climate change and its consequences to take the right measures at the right time and at the right place. This Annual Bulletin on the Climate – it is the 15th issue now – is one of the main contributions to the provision of climate information especially devoted to our Region VI as it combines valuable national information into one summarising, but nevertheless comprehensive report. Its significance also becomes particularly apparent with regard to the future Regional Climate Centre on Climate Monitoring whose pilot phase started in June 2009. The Annual Bulletin gives an overview of climate variability in 2008 in our Region and also contains many noteworthy details about climate events in the various countries. To show what has happened and what can happen in a world where the climate is changing is indispensably needed to assess what the future will bring and whether this will be more frequent than today. The year 2008 has taught us another lesson about how contrasting climate variability can be in our Region which doubtlessly shows a very heterogeneous climate. The winter of 2007/08 was very mild particularly in northeast Europe but unusually cold in the Middle East. Some places in northern and northwestern Europe experienced their wettest year on record whereas Spain suffered from a long-lasting winter-spring drought. These contrasts are the result of the interaction of various circulation mechanisms which influence our regional climate and which are also embedded in the general global climate change manifesting itself in our Region. 2008 was once more one of the warmest years in at least more than 150 years on European average. This presentation of the whole climate information would not have been possible without the numerous national contributions from our Members, the National Meteorological and Hydrological Services. Once again, nearly all Members of the Region (48 out of 50 countries) have sent very interesting articles and figures to our editors at the German Meteorological Service (Deutscher Wetterdienst, DWD). I would like to express my sincere thanks to all contributors and also to the editorial team of DWD, namely to Peter Bissolli, Peer Hechler, Volker Zins and all internal reviewers, for compiling and writing the texts and doing all the editorial and technical work. Congratulations to the colleagues from DWD for their voluntary dedication to all 15 issues of this publication in all these years. Daniel Keuerleber-Burk President of WMO Regional Association VI 6 Annual Bulletin on the Climate in WMO Region VI - 2008 Outstanding Events and Anomalies in 2008 Temperature - Mild winter 2007/08 particularly in northeast Europe - Cold January in the Middle East - Several heat waves in southeastern Europe in summer Precipitation - Wettest year on record in some places in northern Europe - Long winter-spring drought in Spain Sunshine - Sunny February and May in many parts of Europe Annual Bulletin on the Climate in WMO Region VI - 2008 7 Annual Survey 1. Atmospheric circulation Europe commenced the year under a strong zonal (positive) North Atlantic Circulation (NAO) pattern, which continued until March, when a blocking pattern developed over Russia resulting in a strong meridional pattern during April. May saw high pressure dominate northern and central Europe, followed by cyclonic conditions with frequent thunderstorms across central Europe during the summer. A negative phase of the Arctic Oscillation (AO) brought cold Arctic air into northeastern and at times also central and southern Europe from April to September. Conversely, south-westerly flow during the summer across southeastern Europe resulted in several heat waves. In October, a blocking pattern established over Russia and remained there for most of the rest of the year, producing mild conditions over eastern Europe and colder air masses over western Europe. In November, a deep trough extended from Scandinavia to Iberia. The year ended with very cold air flowing from the high latitudes to southeastern Europe and the Middle East on the eastern flank of a central European high pressure system. In contrast to the North Atlantic-European pattern, Greenland, especially its western part, was affected by cold air masses at the beginning of the year. Starting in February/March, however, it was then included in the general Arctic warmth, particularly at the end of the year. The Southern Oscillation Index (SOI), which is a measure of the strength of the El Niño Southern Oscillation phenomenon (ENSO) and is described by the pressure difference between Tahiti (tropical Pacific) and Darwin (Australia), was positive throughout the whole year except a slight negative value in May. Highest values occurred from January to March and again from September to December, while ENSO was weak in late spring and summer. High positive SOI values indicate La Niña conditions. It can be assumed that the La Niña conditions from January to March were related to the parallel positive NAO/AO phase due to the general strengthening of the NAO during La Niña winters. Also, the northward shift of the frontal zone during winter 2007/08 is congruent with La Niña conditions. In November, the La Niña cooling of the East Pacific could have inversely affected the NAO due to a smaller thermal difference on the thermal planetary frontal zone and thus causing weaker west winds also over the North Atlantic. Normally, the ENSO impact on Europe is highest in spring, but as the SOI decreased considerably in spring 2008, there was probably only little impact on spring climate in 2008. The zonal index over central Europe (20°W-40°E, data from DWD) was very high in January- March and again in October-November, with values being considerably higher than normal. April, May and September had negative and below normal values. This reflects the positive NAO/AO mode in January-March and the sudden switch to a strong meridional pattern in April. The high October-November zonality over Europe is in accordance with the AO, but not with the NAO, which suggests that the shift of the Icelandic Low to the central Arctic region nevertheless caused a zonal circulation over Europe. In central Europe, cyclonic weather types dominated throughout the year; anticyclonic types were in majority only in May and October. The total number of days with cyclonic types was considerably higher than normal especially in spring and summer, but also, though to a lesser extent, in other seasons. However, the high number of cyclonic types did not have any major effect on the annual precipitation totals in central Europe. 8 Annual Bulletin on the Climate in WMO Region VI - 2008 2. Temperature Overview Warmer-than-average1 conditions extended across most of Europe in 2008. The mean land surface temperature for the European region (35°N-75°N, 10°W-30°E), as derived from the CRUTEM3 dataset (Climate Research Unit Temperature Version 3, land air temperature anomalies on a 5°x5° grid box basis, http://www.cru.uea.ac.uk/cru/data/temperature/ ), was 1.16±0.17°C above the 1961-90 mean.