A. HACHANI, M. OUESSAR, A. ZERRIM Regional Knowledge Exchange on Decision-support Tools and Models to Project Improved Strategies for Integrated Management of Land, Water and Livelihoods 22-27 September, 2013, Djerba, Tunisia Potential contributions on use of HidroMORE model in olive groves vulnerability to CC A. HACHANI, M. OUESSAR, A. ZERRIM 1

OUTLINE Introduction Materials and methods Results and discussion Conclusions and perspectives

INTRODUCTION Olive tree Importance of plantation of olive trees fluctuation of the olive production

Area (ha) % Number of olive trees Medenine 173000 49.9 3955000 44.9 Gafsa 69030 19.9 2700631 30.7 Gabes 67687 19.5 1353740 15.4 Tatouine 36800 10.7 801000 9.0 Total south 346517 Ministry of agriculture, 2001)

INTRODUCTION Olive trees Climate change(CC) Importance of plantation of olive trees fluctuation of the olive production Climate change(CC) Temperature rainfall Green house 1

Objectives Analyze situation related to climate variability and CC and future projections, Explore different climate scenarios and their effects on water stress olive plantations, Suggest ways and adaptation policies.

Study site

Location

Methodology

Geométric and atmospheric correction climatic data: Baseline period, until 2030 and until 2090 Soil map Land use map Images Landsat 5 and 7 collecting data Geométric and atmospheric correction Treatement NDVI HidroMORE Conceptuel Model

CMIP5 – The Fifth Coupled Model Intercomparison Project. The fifth phase of the Coupled Model Intercomparison Project (CMIP5) produce a state-of-the- art multimodel dataset designed to advance our knowledge of climate change. CMIP5 promotes a standard set of model simulations in order to: • Evaluate how realistic the models are in simulating the recent past, • Provide projections of future climate change on two time scales, near term (out to about 2035) and long term (out to 2100 and beyond),

Choice of model NOAA’s Geophysical Fluid Dynamics Laboratory (GFDL) develops and uses mathematical models and computer simulations to improve our understanding and prediction of the behavior of the atmosphere, ocean, and climate. GFDL is developing a comprehensive global –high resolution atmospheric model (HiRAM C 360)

HidroMore model HidroMORE is considered as an operational model allowing the calculation of the superficial water budget with a limited number of input data HidroMore can detect the water stress of vegetation that can be obtained by the soil water balance

Inputs & outputs

NDVI Cube NDVI images were calculated from Landsat 5 and 7 TM images downloaded from USGS . The images were geometrically and atmospherically corrected For joining all the images as bands in a unique image we have to create the images cube sized to the total area.

NDVI cube NDVI cube

Conceptuel model

Results et discussions

Climate analysis R²=0.8 Test Validation GFDL-HIRAM model

Climate analysis R²=0.8

Calibration

Checking the water balance algorithm HidroMORE. The result of this comparaison provide an efficiency in the implementation of the methodology made by FAO-56 and HidroMORE. 36

ETc adj map (Basline period) 433mm

ETc adj map (H 2030) 378 mm

ETc adj map (H 2090) 299 mm

Rapport ETCadj and ETC Class ETCadj/ETC Perfectly suitable <80 60-80 Moderately suitable 60-40 Slightly suitable 40-20 Not suitable <20

ETCadj/ETC Slightly suitable Moderately suitable suitable Baseline period 28% 46% 26% Horizon 2030 19% 68% 13% Horizon 2090 24% 76%

Baseline period Horizon 2090 Horizon 2030

Adaptative Strategy Develop prediction systems and early warning of drought, Minimize the expansion of olive plantations especially to marginal areas, Encouraging the choice of adapted varieties, Provide emergency irrigation in case of prolonged droughts,

Conclusion The evaluation of water stress of the olive tree within the context of CC in the South East of Tunisia (watershed of Oum Zessar, Medenine) was made using hydrological modeling (HidroMORE model). Model parameterization was based on already conducted studies in the region while estimations have been made of the other case. In comparison with the reference period (1996-2005) and following the increase in temperature (1°C) and (5°C) and rainfall decrease of (5.4%) and (20%), ET0 recorded an increase of (3%) (9%) and ETCadj was reduced by (2%) and (18%), respectively for the 2030 and 2090 horizons. Thus, it is expected that the land suitable for olive cultivation will experience shrinkage and this cropping system would become increasingly problematic. .

Perspectives Push climate analysis to more detailed levels and explore other scenarios projections related to CC, In any work of hydrological modeling (such as Hidromore), there is uncertainty at all levels. Thus, improvements can made ​​through: Further refine the input parameters of the model Using multiple satellite images, Consideration of arrangements for collecting runoff and flood Integrate adaptation scenarios (supplemental irrigation, etc.).

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