1. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA ARPAS Andrea Motroni amotroni@arpa.sardegna.it Climate, climate change and desertification in Sardinia ENVIRONMENTAL PROTECTION AGENCY OF SARDINIA

2. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Agenda Climate characteristics Trends in climate Evidence of climate change? Climate and desertification 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

3. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS The climate of Sardinia is generally classified as Mediterranean Mediterranean climates are located between regions with a tropical-desert climate and those with a marine-coast climate. They generally lie between 30 and 40 degrees latitude. These regions have hot-dry summers and mild-wet winters. 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

4. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS The Mediterranean Basin can be considered as a transitional area between tropical zones, where seasons are determined by rainfall occurrence, and temperate zones, where seasons are determined by variations in temperature values. Consequence : there are great interseasonal variations in precipitation amounts and in temperature values without the extreme values typical of the two climatic areas (Chritchfield, 1983; Martyn, 1992) 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

5. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS General circulation 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

6. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Mediterranean basin is characterized by the highest frequency and concentration of cyclogenesis events. The majority of cyclones are formed in the gulf of Genoa, probably because of Alps position and the high temperature gradient between central-northern Europe and the Mediterranean sea. In the transition periods of March-April and September-October occur the most intense cyclogenetic rain events. Mediterranean climate is influenced by the presence of relevant orographic systems along the Med. Basin -> major cyclones activity 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

7. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS The great seasonal differences are due to northward migration of the upper limit of high pressure cells typical of subtropical areas. In Summer, high pressure cells reach the Mediterranean area causing atmospheric stability which can lead to typical arid subtropical conditions in June, July, August with high maximum temperature values. In the Winter season, the cells leave the Mediterranean sea and lay in north Africa region. Humid air fluxes and cold Polar fronts characterize autumn, winter and partly spring seasons in this area 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

8. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Climate in Sardinia Except for general synoptic situations (atmospheric pressure) - Complex orography - Distance from the sea - Wind Can we talk about climate microregions in Sardinia? 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

9. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Temperature

10. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Temperature in Sardinia Two transition periods before winter and summer –September-November –March-April Depends on orography and altitude: –Thermal inversion in the valley areas –Eastern coast areas protected from cold north-western dominant winds Winter temperature values are mainly determined by the stabilizing effect of the sea (the inner areas of the island show a continental behaviour) Summer temperature values are influenced by stabilizing effect of anticyclonic cells and a north-south gradient can be seen (maximum temperature also west- east) Maximum and minimum temperature values show the same behaviour, but minimum temperature values show less variability 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

11. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS July Mean maximum temperature 1961-90 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

12. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Mean minimum temperature 1961-90 January 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

13. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Climatic mean temperature 1961-90 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

14. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Precipitation 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

15. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Precipitation behaviour (where) 4 rain microregions: –Gennargentu and Ogliastra –Gallura and Limbara –Campeda –Sulcis-Iglesiente 3 dry regions –Nurra –Campidano –Central-north Sardinia (1961-90) 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

16. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Precipitation behaviour (how much) Minimum rain values: –< 400 mm in the south west Maximum rain values –1200 mm (Gennargentu) Regional mean - 600 mm (1961-90) 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

17. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Precipitation behaviour (how) Frequency of rainy events –The areas where we have more than 80 days of rain/year are also the areas where it rains the most......except for the central-east coast (1961-90) 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

18. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Mean annual rainfall 1961-90 …where we have 50 days/year but rain>than average 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

19. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Rainfall regimes on daily basis 1961-90 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

20. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS The north-west and south-west regimes are mainly frontal regimes (higher frequency, not very intense rain events) The central-eastern regime is associated to south-eastern winds which impact the coastal orography in correspondence of cyclones that move along the coast of north Africa leading to convective rain events (less frequent, heavy rain) 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

21. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Wind 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

22. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Frequency of instantaneous wind Calm or variable wind Percent of hours with wind blowing from different directions Calm or variable wind (<1.5 m/s) 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

23. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Monthly means of instaneous wind speed 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

24. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Monthly means of maximum wind speed

25. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Breeze winds in Sardinia

26. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Trends and extreme events 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

27. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Anomaly Index of mean temperature 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

28. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Total Amount Precipitation Index Total amount of P Mean (1961-1990) Standard Dev. (1961-1990) 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

29. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Precipitation classes – Quality of rain 20-50 mm rain events 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

30. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Mean annual rainfall amounts (1951-2000) Mean annual cumulative reference evapotranspiration (1951-2000) Aridity trends 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

31. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS 4,6% semi-arid 29,8% dry sub-humid 7,5% humid 58,1% sub-humid 1951-00 Aridity Index = P/ETo 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

32. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS 81-90 and 91-00 decades critical for mean temperature raising and rainfall deficit 91-00 the worst due to more frequent extreme events 51-60 slightly dry but with average temperature But... 1997-2003 2004 2009-2010 Aridity index FAO-UNEP (P/ETo) 14 TH European Seminar on Geography of Water Cagliari, June 26th - July 7th, 2011

33. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011 1996-2005 ° driest period/50 ys but… ° carefulness in climate data managing

34. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Precipitation trends SPI 1951-00 year 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

35. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Extreme drought events 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

36. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Mean 1951-00 rainfall total 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

37. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS UNCCD(1):Land degradation in arid, semi-arid and dry/sub-humid areas, resulting from various factors, including climatic variations and human impacts (UNEP, 1994) Definition of desertification (1): United Nations Convention to Combat Desertification 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

38. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS …, i.e. desertification is a complex phenomenon strictly dependent on climate 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

39. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Extreme climatic events: drought/floods Pressures on the territory: overgrazing, uncontrolled urbanization/country areas abandonment… Excessive exploitation of water resources Water contamination Fires and deforestation Causes of desertification in Sardinia Soil salinisation 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

40. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS VQI Vegetation Quality Index SQI Soil Quality Index CQI Climate Quality Index MQI Management Quality Index ESAs 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

41. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Sensitive areas to desertification ESAS Sardinia 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

42. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS Final remarks - there are some signicative trends in changing temperature and rainfall values - they can be controversial both in sign (-/+) and in consistency – time and spatial scale problem climate variability VS. climate change - desertification is a more human induced process than climate- driven further investigation on data and monitoring (for example) with bio- indicators are needed 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011

43. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011 Thank you amotroni@arpa.sardegna.it amotroni@arpa.sardegna.it

44. AGENZIA REGIONALE PER LA PROTEZIONE DELLAMBIENTE DELLA SARDEGNA - ARPAS 14 TH European Seminar on Geography of Water - Cagliari, June 26th - July 7th, 2011