Malta’s projected temperature and rainfall are expected to significantly change by the end of 21st century. This important result stems from a comprehensive evaluation of Malta’s climate extremes on the local agriculture sector as projected by the Coupled Model Intercomparison Project phase 5 (CMIP5) multi-model dataset has never been carried out in Malta.
In this study, Dr Charles Galdies and Ms Kimberly Vella, from the Institute of Earth Systems, addressed this gap by conducting a thorough analysis of the CMIP5 climate models’ projections of our local climate, demonstrating that it is precisely in the ability to synthesise complex information that the value of the CMIP5 multi-model dataset can be used as a tool for specific decision-making.
The main aim of this study was to utilize CMIP5 multi-model dataset to analyse in detail the available long-term climate projections and to reflect on the relevant future risks to Maltese agriculture. The analysis uses the latest results from an ensemble of 11 CMIP5 climate models addressing IPCC’s four Representative Concentration Pathways (RCPs) for the years 2050 and 2070. The use of downscaled climate projections was important to anticipate climate change impacts at the local level.
This is seen an important improvement on current knowledge. Local researchers have so far focused their efforts to assess future climate change projections based on single regional model simulations; however, the analysis of this single model output was restricted to a physical understanding of the future climate and never directly extrapolated to local action within any particular sector, including agriculture. Therefore multi-model projections of local precipitation and its related extremes, together with temperature fluctuations and bioclimatic factors in Malta have yet to be investigated.
By means of statistical, empirical crop- and livestock modelling techniques, this unique study shows that future climate change is likely to negatively affect Malta’s natural freshwater supplies, livestock and crop survival. As a consequence, the distribution of the already stressed local arable land will change, modifying production patterns and economics. The analysis of multi-model predictions provided a more robust evaluation of the likely impacts of physical and bioclimatic factors that are of relevance to local agriculture. Irrespective of which RCP scenario is considered, we find that the expected losses in productivity and food quality will be significant.
This Springer Book chapter shows how Malta’s projected temperature and rainfall are expected to significantly change by the end of 21st century. Higher temperatures and lower and more variable rainfall will tend to increase water demand per unit of irrigated area. According to the resultant projected bioclimatic and evapotranspiration estimations for 2070 under a realistic future climate change scenario (RCP 6.0; intermediate GHG emissions), Malta’s arable land would need at least an additional 6m3 of water a day to make up for the expected increased water loss. A 2010 Census of Agriculture revealed that the total registered volume of water used for irrigation in the Maltese islands is 28,176,000 m3/yr applied to at least 3653ha of irrigated arable land. By 2070, we estimate that this amount has to be augmented by an additional 2190 m3/ha/yr, equivalent to 7.9 million m3 of freshwater per annum. The already existent scarcity of surface water supply through reservoirs and ground water is likely to spatially limit the future potential for irrigation, which has critical implications for future crop production.
View the book containing the paper by visiting the publisher's website.
View the book containing the paper by visiting the publisher's website.