Assessment of Local Climate Change: Historical Trends and RCM Multi-Model Projections Over the Salento Area (Italy)

This study provides an up-to-date analysis of climate change over the Salento area (southeast Italy) using both historical data and multi-model projections of Regional Climate Models (RCMs). The accumulated anomalies of monthly precipitation and temperature records were analyzed and the trends in the climate variables were identified and quantified for two historical periods. The precipitation trends are in almost all cases not significant while the temperature shows statistically significant increasing tendencies especially in summer. A clear changing point around the 80s and at the end of the 90s was identified by the accumulated anomalies of the minimum and maximum temperature, respectively. The gradual increase of the temperature over the area is confirmed by the climate model projections, at short—(2016–2035), medium—(2046–2065) and long-term (2081–2100), provided by an ensemble of 13 RCMs, under two Representative Concentration Pathways (RCP4.5 and RCP8.5). All the models agree that the mean temperature will rise over this century, with the highest increases in the warm season. The total annual rainfall is not expected to significantly vary in the future although systematic changes are present in some months: a decrease in April and July and an increase in November. The daily temperature projections of the RCMs were used to identify potential variations in the characteristics of the heat waves; an increase of their frequency is expected over this century.

[1]  L. S. Pereira,et al.  Crop evapotranspiration : guidelines for computing crop water requirements , 1998 .

[2]  P. Sen.  Estimates of the Regression Coefficient Based on Kendall's Tau , 1968 .

[3]  R. Vautard,et al.  EURO-CORDEX: new high-resolution climate change projections for European impact research , 2014, Regional Environmental Change.

[4]  Judit Bartholy,et al.  Med-CORDEX initiative for Mediterranean climate studies , 2016 .

[5]  M. Trnka,et al.  Multi-GCM projections of future drought and climate variability indicators for the Mediterranean region , 2014, Regional Environmental Change.

[6]  P. Martano,et al.  Infiltration and Short-Time Recharge in Deep Karst Aquifer of the Salento Peninsula (Southern Italy): An Observational Study , 2018 .

[7]  J. Christensen,et al.  On the need for bias correction of regional climate change projections of temperature and precipitation , 2008 .

[8]  M. Turco,et al.  Bias correction and downscaling of future RCM precipitation projections using a MOS‐Analog technique , 2017 .

[9]  T. C. Chamberlin.  The Method of Multiple Working Hypotheses , 1931, The Journal of Geology.

[10]  Khaled H. Hamed,et al.  A modified Mann-Kendall trend test for autocorrelated data , 1998 .

[11]  M. Fnais,et al.  Projected changes in heat wave characteristics in the eastern Mediterranean and the Middle East , 2016, Regional Environmental Change.

[12]  G. Tselioudis,et al.  Long term precipitation trends and variability within the Mediterranean region , 2011 .

[13]  J. Seibert,et al.  Bias correction of regional climate model simulations for hydrological climate-change impact studies: Review and evaluation of different methods , 2012 .

[14]  Valeria Monno,et al.  Cascading vulnerability scenarios in the management of groundwater depletion and salinization in semi-arid areas , 2018, International Journal of Disaster Risk Reduction.

[15]  A. Mariotti,et al.  Future Climate Projections , 2013 .

[16]  P. Alpert,et al.  Climatic trends to extremes employing regional modeling and statistical interpretation over the E. Mediterranean , 2008 .

[17]  P. Linden,et al.  ENSEMBLES: Climate Change and its Impacts - Summary of research and results from the ENSEMBLES project , 2009 .

[18]  F. Giorgi,et al.  Climate change hot‐spots , 2006 .

[19]  Jay R. Alder,et al.  Dynamically downscaled climate simulations over North America: Methods, evaluation, and supporting documentation for users , 2011 .

[20]  P. Lionello,et al.  Sensitivity of typical Mediterranean crops to past and future evolution of seasonal temperature and precipitation in Apulia , 2014, Regional Environmental Change.

[21]  P. Steduto,et al.  Prediction of Climatic Change for the Next 100 Years in the Apulia Region, Southern Italy , 2007 .

[22]  J. D. Wilson,et al.  The use of cumulative monthly mean temperature anomalies in the analysis of local interannual climate variability , 1989 .

[23]  M. L. Kurnaz,et al.  Projections of climate change in the Mediterranean Basin by using downscaled global climate model outputs , 2015 .

[24]  H. B. Mann.  Nonparametric Tests Against Trend , 1945 .

[25]  F. Giorgi,et al.  Climate change projections for the Mediterranean region , 2008 .

[26]  H. Moradkhani,et al.  Escalating heat-stress mortality risk due to global warming in the Middle East and North Africa (MENA). , 2018, Environment international.

[27]  M. D’Oria,et al.  Historical trends and high-resolution future climate projections in northern Tuscany (Italy) , 2017 .