Abstract:

In this study, the trends and variability of annual precipitation totals and annual rain days over land within the Mediterranean region are analyzed. Long term ground-based observations concerning, on one hand, monthly precipitation totals (1900-2010) and rain days (1965-2010) from 40 meteorological stations within the Mediterranean region were obtained from the Hellenic National Meteorological Service and the World Climate Data and Monitoring Programme (WCDMP) of the World Meteorological Organization. On the other hand, high spatial resolution (0.5 × 0.5 ) gridded monthly data CRU TS 3.1 were acquired from the Climatic Research Unit, University of East Anglia, for the period 1901-2009. The two datasets were compared by means of trends and variability, while the influence of the North Atlantic Oscillation (NAO) in the Mediterranean precipitation was examined. In the process, the climatic changes in the precipitation regime between the period 1961-1990 (reference period) and the period 2071-2100 (future climate) were presented using climate model simulations (RACMO2.1/KNMI). The future climate projections were based on SRES A1B.

The findings of the analysis showed that statistically significant (95% confidence level) negative trends of the annual precipitation totals exist in the majority of Mediterranean regions during the period 1901-2009, with an exception of northern Africa, southern Italy and western Iberian peninsula, where slight positive trends (not statistically significant at 95% CL) appear. Concerning the annual number of rain days, a pronounced decrease of 20 %, statistically significant (95% confidence level), appears in representative meteorological stations of east Mediterranean, while the trends are insignificant for west and central Mediterranean. Additionally, NAO index was found to be anticorrelated with the precipitation totals and the number of rain days mainly in Spain, southern France, Italy and Greece. These correlations are higher within the rain season (October-March) than the entire year. Based on the results of regional climate model RACMO2.1/KNMI, precipitation is very likely to decrease almost 20% in the period 2071-2100 compared to 1961-1990, under SRES A1B. © Author(s) 2011.

Notes:

Cited By :20Export Date: 2 November 2015Correspondence Address: Nastos, P.T.; Laboratory of Climatology and Atmospheric Environment, Faculty of Geology and Geoenviroment, National and Kapodistrian University of AthensGreece; email: nastos@geol.uoa.grReferences: Alpert, P., Ben-Gai, T., Baharad, A., Benjamini, Y., Yekutieli, D., Colacino, M., Diodato, L., Manes, A., The paradoxical increase of Mediterranean extreme daily rainfall in spite of decrease in total values (2002) Geophys. Res. Lett, 29, pp. 311-314;Brunetti, M., Maugeri, M., Nanni, T., Changes in total precipitation, rainy days and extreme events in Northeastern Italy (2001) International Journal of Climatology, 21 (7), pp. 861-871. , DOI 10.1002/joc.660; Brunetti, M., Caloiero, T., Coscarelli, R., Gull̀a, G., Nanni, T., Simolo, C., Precipitation variability and change in the Calabria region (Italy) from a high resolution daily dataset (2010) Int. J. Climatol, , doi:10.1002/joc.2233 online first; Buffoni, L., Maugeri, M., Nanni, T., Precipitation in Italy from 1833 to 1996 (1999) Theoretical and Applied Climatology, 63 (1-2), pp. 33-40. , DOI 10.1007/s007040050089; Cullen, H.M., DeMenocal, P.B., North Atlantic influence on Tigris-Euphrates streamflow (2000) International Journal of Climatology, 20 (8), pp. 853-863. , DOI 10.1002/1097-0088(200 00630)20:8<853::AID-JOC 497>3.0.CO;2-M; Dunkeloh, A., Jacobeit, J., Circulation dynamics of Mediterranean precipitation variability 1948-98 (2003) International Journal of Climatology, 23 (15), pp. 1843-1866. , DOI 10.1002/joc.973; (2011) RCM-specific Weights Based on Their Ability to Simulate the Present Climate, Calibrated for the ERA40-based Simulations, , www.ensembleseu.org, ENSEMBLES Deliverable D3.2.2 available at (last access: 20 February 2011); Feidas, H., Noulopoulou, Ch., Makrogiannis, T., Bora-Senta, E., Trend analysis of precipitation time series in Greece and their relationship with circulation using surface and satellite data: 1955-2001 (2007) Theoretical and Applied Climatology, 87 (1-4), pp. 155-177. , DOI 10.1007/s00704-006-0200-5; Folland, C.K., Karl, T.R., Observed climate variability and change (2001) Climate Change 2001: The Scientific Basis, pp. 99-181. , Contribution of Working Group 1 to the Third IPCC Scientific Assessment, edited by: Houghton, J. T., Ding, Y., Griggs D. J., Noguer, M., van der Linden, P. J., Dai, X., Maskell, K., and Johnson, C. A. , Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA; Forland, E., Van Engelen, A., Hanssen-Bauer, I., Heino, R., Ashcroft, J., Dahlstr̈om, B., Demaŕee, G., Vedin, H., (1996) Changes in Normal Precipitation in the North Atlantic Region, , Klima Report 7/96, The Norwegian Meteorological Institute, Oslo; Goodess, C.M., Jones, P.D., Links between circulation and changes in the characteristics of Iberian rainfall (2002) International Journal of Climatology, 22 (13), pp. 1593-1615. , DOI 10.1002/joc.810; Guijarro, J.A., Jans̀a, A., Campins, J., Time variability of cyclonic geostrophic circulation in the Mediterranean (2006) Adv. Geosci, 7, pp. 45-49. , doi:10.5194/adgeo-7-45-2006; Hurrell, J.W., Decadal trends in the North Atlantic oscillation: Regional temperatures and precipitation (1995) Science, 269 (5224), pp. 676-679; Hurrell, J.W., Van Loon, H., Decadal variations in climate associated with the North Atlantic oscillation (1997) Climatic Change, 36 (3-4), pp. 301-326; (2007) The Physical Science Basis, , IPCC Contribution of Working Group 1 to the Fourth IPCC Assessment Report, Chapter 11 Regional Climate Projections; Jones, P.D., J́onsson, T., Wheeler, D., Extension to the North Atlantic Oscillation using early instrumental pressure observations from Gibraltar and South-West Iceland (1997) Int. J. Climatol, 17, pp. 1433-1450; Karl, T., Knight, R., Secular trends of precipitation amount frequency and intensity in the United States (1998) Bull. Am. Met. Soc, 79, pp. 232-241; Kutiel, H., Maheras, P., Guika, S., Circulation and extreme rainfall conditions in the eastern Mediterranean during the last century (1996) Int. J. Climatol, 16, pp. 73-92; Lenderink, G., Van Den Hurk, B., Van Meijgaard, E., Van Ulden, A.P., Cuijpers, J.H., Simulation of present-day climate in RACMO2: First results and model developments (2003) KNMI Technical Report, 252, p. 24; Lionello, P., Dalan, F., Elvini, E., Cyclones in the Mediterranean Region: The present and the doubled CO2 climate scenarios (2002) Clim. Res, 22, pp. 147-159; Lionello, P., Bhend, J., Buzzi, A., Della-Marta, P.M., Krichak, S., Jans, Ã.A., Maheras, P., Trigo, R., Cyclones in the Mediterranean region: Climatology and effects on the environment (2006) Mediterranean Climate Variability, pp. 324-372. , edited by: Lionello, P., Malanotte-Rizzoli, P., abd Boscolo, R., Amsterdam Elsevier, Netherlands; Luterbacher, J., Xoplaki, E., Casty, C., Wanner, H., Pauling, A., Kiittel, M., Rutishauser, T., Le Roy Ladurie, E., Chapter 1, Mediterranean climate variability over the last centuries: A review (2005) The Mediterranean Climate: An Overview of the Main Characteristics and Issues, , edited by: Lionello, P., Malanotte-Rizzoli, P., and and Boscolo, R., Elsevier; Maheras, P., Kolyva-Mahera, F., Temporal and Spatial characreristics of annual precipitation over Balkans in the twentieth century (1990) Int. J. Climatol, 10, pp. 495-504; Maheras, P., Flocas, H., Patrikas, I., Anagnostopoulou, C.H., A 40 year objective climatology of surface cyclones in the Mediterranean region: Spatial and temporal distribution (2001) Int. J. Climatol, 21, pp. 109-130; Mantis, H.T., Repapis, C.C., Philandras, C.M., Paliatsos, A.G., Amanatidis, G.T., The spatial and temporal structure of the precipitation climate the Eastern Mediterranean, Background for a study of Climate Change (1994) EUR 17458-Eastern Europe and Global Change, pp. 125-131. , edited by: Ghazi, A., Mathy, P., and Zerefos C., Greece; Metaxas, D.A., Philandras, C.M., Nastos, P.T., Repapis, C.C., Variability of Precipitation pattern in Greece during the year (1999) Fresen. Environ. Bull, 8, pp. 1-6; Mitchell, T.D., Jones, P.D., An improved method of constructing a database of monthly climate observations and associated high-resolution grids (2005) International Journal of Climatology, 25 (6), pp. 693-712. , DOI 10.1002/joc.1181; Nastos, P.T., Spatial and temporal variation of rain intensity in Greece (2008) Proceedings of 8th International Hydrogeological Congress, pp. 651-660. , Athens, Greece; Nastos, P.T., Zerefos, C.S., On extreme daily precipitation totals at Athens, Greece (2007) Advances in Geosciences, 10, pp. 59-66; Nastos, P.T., Zerefos, C.S., Decadal changes in extreme daily precipitation in Greece (2008) Adv. Geosci, 16, pp. 55-62. , doi:10.5194/adgeo-16-55-2008; New, M., Hulme, M., Jones, P., Representing twentieth-century space-time climate variability. Part I: Development of a 1961-90 mean monthly terrestrial climatology (1999) Journal of Climate, 12 (3), pp. 829-856; New, M.G., Hulme, M., Jones, P.D., Representing twentieth century space time climate fields, Part II: Development of a 1901-1996 mean monthly terrestrial climatology (2000) J. Climate, 13, pp. 2217-2238; Paliatsos, A.G., Nastos, P.Th., Tzavelas, G., Panagiotakos, D.B., Characteristics of precipitation in the Athens area, Greece (2005) Fresenius Environmental Bulletin, 14 (5), pp. 422-428; Palutikof, J.P., Trigo, R.M., Adcock, S.T., Scenarios of future rainfall over the Mediterranean: Is the region drying? (1996) Proceedings of Mediterranean Desertification, Research Results and Policy Implications, , Crete, Greece; Piervitali, E., Colacino, M., Conte, M., Signals of climatic change in the central-western Mediterranean Basin (1997) Theoretical and Applied Climatology, 58 (3-4), pp. 211-219; Piervitali, E., Colacino, M., Conte, M., Rainfall over the central-western Mediterranean basin in the period 1951-1995, Part I: Precipitation trends (1998) Il Nuovo Cimento, 21 C, pp. 331-344; Pnevmatikos, J.D., Katsoulis, B.D., The changing rainfall regime in Greece and its impact on climatological means (2006) Meteorol. Appl, 13, pp. 331-345; Repapis, C.C., Temporal fluctuations of precipitation in Greece (1986) Riv. Meteorol. Aeron, 46, pp. 19-25; Schonwiese, C., Rapp, J., (1997) Climate Trend Atlas of Europe Based on Observations 1891-1990, p. 224. , Kluwer Academic Publishers, Dordrecht; Schonwiese, C.D., Rapp, J., Fuchs, T., Denhard, M., Observed climate trends in Europe 1891-1990 (1994) Meteorol. Z., NF, 38, pp. 51-63; Sneyers, R., (1975) Sur l' Analyse Statistique des Series d'Observations, , Technical Note 143, WMO, Geneva; Tiedtke, M., A comprehensive mass flux scheme for cumulus parameterization in large-scale models (1989) Mon. Weather. Rev, 117, pp. 1779-1800; Tiedtke, M., Representation of clouds in large-scale models (1993) Monthly Weather Review, 121 (11), pp. 3040-3061; Trigo, I.F., Davies, T.D., Bigg, G.R., Decline in Mediterranean rainfall caused by weakening of Mediterranean cyclones (2000) Geophysical Research Letters, 27 (18), pp. 2913-2916. , DOI 10.1029/2000GL011526; Tselioudis, G., Zerefos, C., Zanis, P., Repapis, C., Kapspmenakis, I., Future trends in mediterranean precipitation and pos sible connections with the phase of the North Atlantic Oscillation (2008) Proceedings 9th Conference of Meteorology, Climatology and Atmospheric Physics, pp. 513-520. , Thessaloniki 28-31 May 2008; Turkes, M., Influence of geopotential heights, cyclone frequency and Southern Oscillation on rainfall variations in Turkey (1998) International Journal of Climatology, 18 (6), pp. 649-680. , DOI 10.1002/(SICI)1097-0088(1998 05)18:6<649::AID-JOC269>3. 0.CO;2-3; Ulbrich, U., Christoph, M., A shift of the NAO and increasing storm track activity over Europe due to anthropogenic greenhouse gas forcing (1999) Climate Dynamics, 15 (7), pp. 551-559. , DOI 10.1007/s003820050299; Van Meijgaard, E., Van Ulft, L.H., Van De Berg, W.J., Bosveld, F.C., Van Den Hurk, B.J.J.M., Lenderink, G., Siebesma, A.P., (2008) The KNMI Regional 844 Atmospheric Climate Model RACMO Version 2.1, , KNMI Technical Report, 845 TR-302. KNMI, De Bilt; Xoplaki, E., Luterbacher, J., Burkard, R., Patrikas, I., Maheras, P., Connection between the large scale 500 hPa geopotential height fields and precipitation over Greece during wintertime (2000) Clim. Res, 14, pp. 129-126; Xoplaki, E., Gonzalez-Rouco, J.F., Luterbacher, J., Wanner, H., Wet season Mediterranean precipitation variability: Influence of large-scale dynamics and trends (2004) Climate Dynamics, 23 (1), pp. 63-78. , DOI 10.1007/s00382-004-0422-0; Zhang, X., Hogg, W.D., Mekis, E., Spatial and temporal characteristics of heavy precipitation events over Canada (2001) Journal of Climate, 14 (9), pp. 1923-1936

Website