Agriculture is a particularly sensitive sector to the potential impacts of climate change - crop water requirements and seasonal distribution of water demand can be impacted. There are other factors that could lead to variations in the cropping pattern and water requirements, thus, irrigation infrastructure needs to be robust.
This case study deals with tasks that a water irrigation manager has to perform in order to assess and quantify the economic damages and risk posed by climate change to irrigated crops and identify the best adaptation/mitigation options in order to avoid or minimize the damages.
Climate services and indicators are useful to raise awareness on the challenges that climate change pose. New tools and data give irrigation managers the possibility to evaluate climate risks and support risk management for irrigation in the context of climate change.
Case Study Description
The Romagna Land Reclamation and Irrigation Authority is in charge to maintain and develop the irrigation network in order to meet irrigation demand and minimize agricultural damages in a small agricultural district in the Province of Forlì-Cesena, Rimini and Ravenna (Italy).
Irrigation managers need information on how soil water balance and irrigation demand might change in future, to plan adaptation/mitigation options or new investments in irrigation network and assess the economic damages and risk to irrigated crops.
Through a bottom-up approach to better fulfill the customer's needs and tackle some of its decision making challenge, a simplified soil water balance indicator has been developed (Wetness 1) and combined with crops water demand and irrigation availability in order to assess the agricultural economic damages for the study area. Wetness 1 data provided by SWICCA portal at decadal values has been validated and downscaled to 2 km of spatial resolution, the indicator provides high-resolution information useful for predicting the spatial variation of soil water content (Wetness1 indicator) and consequently the water irrigation needs under climate change scenarios
In particular, the cumulative sum of decadal values representative for each irrigation district can be efficiently adopted by irrigation managers in order to assess the following aspects:
- quantify the variation of duration (number of decades) of negative values of the Wetness1 cumulative sum;
- identify and locate the most critical irrigation districts in terms of soil water availability and increases in irrigation demand;
- evaluate if the existing irrigation network can respond to new water irrigation demands;
- quantify yield losses and identify the best adaptation and mitigation options.
Climate services represent an effective tool to assist irrigation managers in infrastructure planning and mitigation implementation. In addition, climate services and indicators are useful to raise awareness on the challenges that climate change pose, particularly for organizations that have not yet taken climate change into consideration. There are currently no such kind of tools and data available to irrigation managers. These new tools and data give irrigation managers the possibility to evaluate climate risks and support irrigation risk management in the context of climate change.
The case study has been developed in order to support the local irrigation water manager in coping with climate change challenges and evaluating climate risk and adaptation/mitigation strategies. In the next few months, multiple water saving strategies and new irrigation technologies will be discussed and evaluated in order to adapt to possible economic damages posed by climate change as evaluated in the Castiglione district case study.
The evolution of BIC under climate change scenarios should be implemented for every agricultural district characterized by a spatial resolution of approximately 2 km.
The temporal scale the BIC is evaluated weekly or every 10 days (decadal) during the year, concerning the timeframe of climate change adaptation planning was selected between 5 and 30 years (average lifetime of a irrigation network is equal to 25 years)
The absolute decadal values (every 10 days) of the Wetness1 indicator has been downloaded at 5km and E-HYPE catchments spatial resolution. Subsequently a simplified downscaling procedure has been implemented in order to obtain and map the indicator with a spatial resolution of 2 km.
The selection and design of SWICCA indicator has been made through a bottom-up approach characterized by a full involvement of the client.
From 2015 to 2017, the client has been directly involved in six formal on-site meetings and was kept in permanent liaison (through email and telephone) in order to obtain useful feedbacks and problem-solving suggestions. The six meetings concerned the following topics:
- SWICCA project description, Problem Solving Analysis, Climate Change Challenged and SWICCA indicator definition
- Data Collection and analysis
- analysis and discussion of the downscaled Wetness1 indicator;
- definition of real case studies and their application;
- analysis and discussion about climate change scenario uncertainty and the best way to communicate the results
- evaluation of economical damages based on soil water budget and crops water requirments
The first meeting with Client was held in December 2015 and introduced the project and decided the workflow. The meeting in March 2016 focused on meteorological data collection and analysis in order to produce high spatial resolution data suitable for climate risk assessment and management. The 3rd meeting took place in June 2016 has analyzed in detail the first outcomes from the downscaled version of the selected indicator. The meeting held in Oct 2016 focused on defining two real case study and in acquiring the data. The Castiglione and Branchise case study were defined in details and data concerning irrigation network capacity and crops characteristics were acquired. Last meetings have been held in 2017 in order to explore and discuss the overcomes from the developed real case study. In particular, meeting of 15th May 2017 was focused on uncertainty assessment and communication and the meeting of 12th July 2017 on economic quantification of reduction of yield due to water deficit condition, in order to complete assessment on case study.
The main indicator used in the irrigation strategies case study is the Wetness1 indicator. It is provided by the SWICCA interface at a decadal time frame resolution in absolute (mm/decadal) or relative change (%). In order to support irrigation strategies, absolute values of Wetness1 areas are reported as a cumulative sum to better evaluate the amount of irrigation water needed per specific crop. The user can modify the cumulative sum of the indicator by specifying the amount of water provided through irrigation and the evaporation crop coefficient (kc) for correcting the PET.
Neither local indicators for climate change scenarios nor decision support system are available. The client does not currently take into account climate change scenarios, both short- and long-term, in its decision-making process. The local indicators provided by the Emilia-Romagna Region entails only seasonal predictions without any information or data concerning the long-term scenarios.
Step 1: Run and validate a soil water balance model in order to predict soil water content (SWC) or soil water budget (P-PET) in a climate change scenario. SWC is obtained as results from specific hydrological model (ex. LISFLOOD or EHYPE) while Soil Water Budget is simply calculated as difference between Precipitation and potential evapo-transpiration in climate change conditions.
Step 2: Spatial downscaling to a resolution of 1 or 2 km suitable for the case study
Step 3: Mapping SWC or P-PET with a temporal timeframe of 10 days in the study area.
Step 4: Mapping the climate change irrigation risk for agriculture in the study area and identification of area where adaptation or mitigation measures should be adopted.
Step 5: Define the plan of mitigation/adaptation measures.
Step 6: Define and evaluate the cost-benefit of multiple mitigation/adaptation measures:
- Temperature and Precipitation variation in climate change scenario
- Downscale at spatial resolution of 2 km
- Time scale 10 days
- Estimate ET and Soil Water Balance (BIC) using a soil water budget model (LISFLOOD FP)
- Map the BIC climate change variation in the study area
- Evaluate the economical and planning consequences
Considering the entire workflow, the main successful factor in the suggested implementation of indicators are:
- the AGILE approach and the flexibility of implementing climate change information (by downscaling SWICCA data to irrigation districts resolution) inside the currently used and updated Soil Water Balance Indicator (BIC), clearly a saving time option for both the Authority and the Purveyor,
- The online SWICCA demonstrator interface that is quite easy to use and to take data from for the area of interest.
- The dedicated web mapping climate service developed for this case study and available at http://www.climate-tools.com/swicca/view/index/index.html
Main Limiting factor is the necessity to identify the most reasonable subset of combinations and scenarios of C.C. to be implemented in the final indicators and to be used by the Client. Going deeper in the step by step workflow, successful and limiting factors are summarised below:
Step 1: SWICCA Wetness1 Low Resolution Climate Data are useful for a preliminary evaluation in order to identify the major irrigation and agricultural area at risk. No limiting factor, SWICCA interface provides easy access to indicators.
Step 2: Spatial downscaling to a resolution of 1 or 2 km suitable for the case study Successful factor is mainly the easiness to adapt current Wetness1 information in Climate Change recurring to simplified downscaling procedure. The limiting factor consists in knowledge gap in using more refined downscaling procedures. The newly available Wetness1 data at 5 km resolution should be easier to downscale.
Step 3: Mapping Wetness1 with a temporal timeframe of 10 days in the study area and Step 4: Mapping climate risk for agriculture and identification of areas where adaptation and/or mitigation measures should be adopted
The spatial interpolation of point downscaled data provides high resolution maps (2 km) of Wetness1 indicator. The maps of Wetness1 are a very useful tool for spatially estimate the increase in water irrigation demand. No major obstacles or limiting factors in this step
Step 5: Climate Risk Assessment: Evaluate the risk and economic damages on agriculture and Step 6: Climate Risk Management: Planning and designing of a new water irrigation system Main limiting factor has been the wide range of possible combination and scenarios of C.C. to be reasonably reduced both for implementation purposes and for communication of added value to the Client, we explored the use of a web mapping service available as prototype at http://www.climate-tools.com/swicca/view/index/index.html also to make decision from different scenarios easier to handle, moreover considering probabilistic evaluations on Climate Change conditions.
Agriculture is an important economic driver and the main water demanding sector in Europe, and in the Emilia-Romagna Region in particular. An efficient management of irrigation water is key to tackle economic and environmental challenges. The SWICCA approach and climate data provide a valuable tool and support to the decision-making process, helping it to take steps towards sustainability and climate change resilience.
“SWICCA has highlighted the risks associated with climate change and this will help us to validate new and existing irrigation proposals ... and will help us to protect crops and ultimately safeguard agriculture through irrigation strategies that anticipate the water shortages that could come with climate change,” Domenichini - Romagna Land Reclamation and Irrigation Authority.
The case study implemented in SWICCA demonstrates how climate change scenario, in particular the 2080 horizon, might affects the actual irrigation system and contribute to economic damages in terms of crop yield. Ignoring changes in water availability, soil water budget and crop irrigation needs could pose the entire irrigation network at risk in terms of fulfilling the irrigation water demand.
The implemented climate service can support the irrigation managers in efficiently select the main irrigation branches under the risk of climate scenario and lead to a higher level of preparedness, making the client ready to plan long term adaptation strategies and more resilient against economic damages.
In Emilia-Romagna Region, actions have been planned to consider climate change effects in the management of water resources as reported in the Climate Change and Water Planning report (Regione Emilia Romagna 2003), the Water Protection Plan (2005) and the Regional Drought Management Plan. In particular, the last two documents refer to management of water resources in order to face drought and monitoring risks at local and regional scales, and identify appropriate short and long-term responses to drought in the agricultural and water provision sectors.
Romagna Land Reclamation and Irrigation Authority (CBR) performs a constant monitoring of water volumes conveyed in the territory. This is in regard to the pressure systems, and the volumes put into the drainage channels to use exclusive irrigation. Thus, they can act almost in real time on the adjustment of the hydraulic equipment to manage water resources in the most efficient manner possible. The proposed indicator can assist Irrigation Authority in defining and planning drought management plans by providing information to minimize economical and environmental damages on agricultural areas.
In particular three policy options are available in terms of irrigation water saving:
- regulative approach: limitation of the installation of new higly water exigent crops (actinidia) or increase in the area of the existing ones;
- tariff approach: establishment of a mc water tariff collected, varies based on water availability in the rivers, subject to the DMV;
- market approach: allocation of water abstraction quotas determined based on actual water availability in the area, subject to maintaining the DMV of the summer months, based on the UAA producers and establishment of the allowance market (analogue of the allowance market carbon: those who consume more than the allocated quota must buy allowances from those who do not consume all their own).
Ing. Stefano Bagli, PhD
GECOsistema srl – Geographic Environmental Consulting
Base Office: viale Carducci, 15 – I-47521 Cesena (FC) – Tel/Fax (+39) 0547 22619
Unità R&D Suedtirol: via Maso della Pieve/Pfarrhofstr, 60/A- I-39100 Bolzano (BZ)
Legal Seat: Piazza Malatesta, 21- I-47923 Rimini (RN)
P.IVA 03236780403 – www.gecosistema.com
Consorzio di Bonifica della Romagna (Italy)
Romagna Land Reclamation and Irrigation Authority, Cesena, Italy
Purveyor: Stefano Bagli – GECOsistema srl
Value added by Copernicus Climate Change Service:
Client: Consorzio di Bonifica della Romagna (Italy)
Romagna Land Reclamation and Irrigation Authority, Cesena, Italy
c.p. Eng. Daniele Domenichini