In this section, the results of the hazard, intermediate impact, and vulnerability assessments, as well as of the total impact assessment, are presented and critical issues are identified and discussed. Following, an economic assessment is made on the expected gains and losses, based on the results of the intermediate impacts on crop yield change.
3.1. Hazard
A comprehensive analysis of mean and extreme climate change indicators relevant to agriculture was undertaken. According to the results of the analysis, an increase in the seasonal average temperature is expected for all seasons under RCP4.5, which will be up to 2 °C for winter, 3 °C for summer, and 2.4 °C for the transient seasons. Under the RCP8.5 scenario, greater increases are projected throughout the year, that is, up to 2.3 °C for winter, 3.8 °C for summer, and 3 °C for the transient seasons.
Concerning the average annual total precipitation, under the RCP4.5 scenario, the highest decreases of about 10% are projected in southern and southeastern regions of the island, while under the RCP8.5 scenario, decreases of about 10% in western and mountainous regions and 15% in all other regions are expected.
Regarding the precipitation seasonal changes, small increases in winter precipitation of up to 10% in the western coastal regions under the RCP8.5 scenario are found, while spring precipitation decreases approximately 20% throughout the island. During summer, under both scenarios, the entire island shows decreases, with the maximum of 60% located in the western coastal areas under RCP4.5 and 50% in the southern-southeastern coastal regions under RCP8.5.
3.2. Intermediate Impact
The results of the climatic hazard assessment for the two RCP scenarios are used in the assessment of crop yield change (intermediate impacts). The interaction between climate, CO
2 concentration, and crop growing cycle (
Table 3) is a key factor to interpret the impact simulated for the crops under study. While higher temperatures and lower precipitation simulated under RCP8.5 are expected to have an adverse effect on crop growth, the higher CO
2 concentration under this scenario mitigates such an impact by increasing photosynthetic and water use efficiency. As a matter of fact, the performances of crops are generally higher under RCP8.5 compared with RCP4.5, as the effect of higher CO
2 concentration (540 vs. 485 ppm) counterbalances the negative effects of climate change. Summer crops are generally more exposed than winter crops, as their growing cycle takes place when drought and heat stress increase in frequency and intensity. While an advanced sowing time may reduce these effects, a delayed sowing further reduces crop yield by shifting crop growing cycle towards the most unfavorable time of the season.
The effect of climate change with respect to the reference period was initially evaluated by considering the possible shifts in sowing dates or the use of different varieties, as outlined in
Table 8. In general, the results indicate that adaptation practices like advanced sowing constitute an effective measure to avoid the summer harsh conditions and reduce the expected impact of climate change. In particular, the early autumn sowing date is found to provide the highest yield for both wheat and barley over Cyprus with respect to the reference period. For RCP4.5, a general reduction of final yield was observed for wheat, ranging from −1.2% in early autumn to −4% in spring. Under RCP8.5, yield increases in early autumn by +5.3% with a decreasing trend up to spring (+3.2%). The same trend was observed for barley, where the yield slightly decreases in early/late autumn (−2.2 and −1.4%) and slightly increased in winter and spring (+0.6 and +0.5%) under RCP4.5. Conversely, under RCP8.5, the yield increases in a range from +3.9% in early autumn to 7.5% in spring.
For the case of tomato, the late winter sowing times provided the highest yield for the reference period. The effect of climate change was generally positive when considering this time window for sowing, while it tended to decrease when shifting the sowing to late spring, where final yield was highly depressed with respect to the reference period up to −27.4% under RCP4.5.
The highest yield for potato crop was reached when sowing was set in winter season (early/late) in the reference period. In future scenarios, the impact on yield was generally positive, especially for late autumn sowing under RCP8.5 that yielded an average increase of 23% with respect to the relevant sowing time.
Grapevine provided the highest yield with a late growing cycle in the reference period, which conversely was the most affected in both RCP4.5 and 8.5 future scenarios (−18.0% and −29.6%, respectively).
A late growing cycle variety of olive tree exhibited the best performances over the island for the reference period. Similarly, both future scenarios had a general positive impact on final yield, especially for the early variety whose yield increased, with a few exceptions, up to +5% in RCP8.5. For the late variety, yield increases were moderate.
These data, in any case, represent the average performances of each crop simulated over the entire island, regardless of where the crops are actually cultivated. The same applies for management practices (sowing time) and varietal choice (late, medium and early) that, while in our simulations maximize final yield, may not be fully applicable in real conditions.
As such, for a real representation of the current growing conditions and management practices in Cyprus, we considered only simulations corresponding to the sowing times and varieties actually applied (
Table 4) (business as usual, BAU). The same procedure was applied to assess the effect of climate change on crop yield change with respect to the reference period, under BAU conditions. The data on crop yield change were aggregated at municipal level by considering the weighted average of (i) the average expected yield change in each Cyprus municipality and (ii) the share of the cultivated area in each municipality to the total cultivated area of that crop in the Cyprus’ municipalities. In a few words, if a crop is not cultivated in an area where a reduction in yield is expected, this reduction is not taken into account for the weighted average yield change.
As shown in
Table 9, the results still point out that, under BAU conditions, on average, the crop mostly at risk is tomato, under both the RCP4.5 and RCP8.5 scenarios (−25% on average), while potato exhibited the best performances (+12%). Winter crops such as winter and barley are less affected with respect to summer crops (tomato and grapevine), as their growing cycle partially avoids the effect of the summer period.
It should be noted that, in the case of tomato, crop simulations only consider open-field conditions, while tomato is mostly cultivated in greenhouses. As such, the outputs may be not fully representative of the expected impact of climate change.
Under extreme climatic scenarios, hot years are expected to mostly affect summer crops (tomato, olive tree, and grapevine), while winter and autumn crops are not affected (wheat and barley) or even are positively influenced (potato). Almost the same trend was observed for the dry years, but not for wheat and barley, which exhibited a high yield decrease (−45% and −51%) that was not observed for potato (+20%), as the likely effect of a general shorter growing season that allowed potato crop to avoid the effect of dryness in summer. Grape and tomato were the most responsive in extremely wet years (+5% and +34%, respectively), while the other crops showed a moderate negative effect (olive tree −5%) or even large decrease (−21% and −33% for barley and wheat, respectively). The latter is somehow unexpected, as wet events were probably associated to cold events in winter that may have affected crop growth, as indicated by the results obtained for cold events. Under these extreme climatic years, both barley and wheat exhibited a reduction (−14% on average), while summer crops presented an increase in their performances, with the exception of tomato, as a result of a longer growing season induced by lower temperatures.
The results also point out that physiological adaptation to a dry climate may reduce the expected impact of climate change in summer season. For example, although olive tree develops during spring-summer, it suffers less in a warmer and dryer climate as it is well adapted to such conditions. In particular, Olive.CNR includes such an adaptation by increasing WUE in response to water stress, resulting into a lower water transpiration while keeping the photosynthetic efficiency.
The results of the crop simulation models obtained for Cyprus are in line with to date literature, which evidenced an asymmetric impact of climatic change on summer and winter crops, especially over the Mediterranean basin. As an example, Moriondo et al. [
25] highlighted that, over the basin, drought and heat stress simulated for the next future in the A2 and B2 scenarios will have no adverse impact or even positive effects for durum wheat. On the same line, Abd-Elmabod et al. [
32] predicted that, under the A1B scenario, sunflower in southern Spain is expected to be more subject to the impact of a warmer and dryer climate with respect to wheat. The same trend was observed on the European scale, where Webber et al. [
33] demonstrated that drought and heat stresses would result in yield losses for maize, while gains are predicted for winter wheat. Ventrella et al. [
34] indicated that a typical summer crop like tomato is at risk in Southern Italy in a +2 °C scenario, if no adaptation measures are taken. Other studies indicated that progressive increase of temperature and drought will affect typical Mediterranean crops, such as olive tree and grapevine, that are expected to progressively shift to north from their original range [
35,
36]. This puts these crops at risk, especially in the south of the Mediterranean.
3.4. Total Impact
The total impact results were calculated based on equations [
1,
2,
3] and are presented for each crop and climatic scenario both cumulatively at national level (
Table 12) and geospatially at municipal level for the whole country (
Figure 1).
In particular, the values in
Table 12 refer to the average of total impact values of the municipalities where each crop is cultivated. On the basis of RCP4.5, the highest impact scores are observed for tomatoes, followed by olives and grapes. In the case of RCP8.5, the hierarchy is somewhat different, with the highest impact scores observed for tomatoes, followed by grapes and then olives. In both scenarios, barley is in the fourth place, followed by wheat with low impact scores, while potatoes present negligible impact scores. In any case, the results of the table must be interpreted with caution, as a high impact score may only have a limited local effect, if the crop is cultivated to a small area (e.g., as in the case of tomato).
The impact assessment results are also presented through maps. However, owing to limited availability of space, it was decided to present only the results based on RCP4.5 (
Figure 1). This selection is also based on the fact that RCP4.5 is a moderately optimistic scenario with respect to the implementation of greenhouse gas (GHG) mitigation policies, which is more in line with the Paris Agreement for limiting global temperature increase to 1.5 °C by 2050 and the respective targets of the European Green Deal (COM (2019) 640) for achieving climate neutrality by 2050. Therefore, it is considered a more realistic scenario in contrast with RCP8.5, which does not take into account any intensification of mitigation policies.
As it may be seen in
Figure 1, the cultivation of barley in Cyprus is expected to face from “low” up to “medium to high” total impacts in the future, while there are also areas where no adverse impacts are expected. The cultivation of wheat is not expected to face particular adverse impacts, with the latter not exceeding “medium” intensity. All areas cultivated with tomatoes are expected to face adverse total impacts, which in some cases reach “high” intensity. The cultivation of potatoes is not expected to be negatively affected by climate change, as there are very few municipalities where adverse impacts are foreseen. In the case of vineyard cultivation, the expected total impacts range from “low” to “medium to high”. Lastly, the cultivation of olives is expected to be considerably affected with adverse impacts mostly ranging from “medium” to “medium to high”, while the mountain area of Troodos is not expected to experience adverse impacts.
The results of the impact assessment may provide an indication of the intensity of impacts expected and of the areas that will be mostly affected; however, more detailed field research and consultation with stakeholders are necessary in order to determine what is needed for adaptation programming and how to develop local resilience.
3.5. Economic Assessment
Ιn this section, the results of the assessment of climate change impacts on the expected changes in revenues from the examined crops under the different climatic scenarios are presented (
Table 13). The results are calculated based on the expected change in yield (
Table 9) and the average price of crops for the period 2010–2015 (
Table 7), based on the assumption that the prices will remain stable in the future.
The results in
Table 13 show that the maximum losses in revenues are expected for an extreme dry year under RCP8.5 with an estimated reduction of 8%, while in the case of an extreme cold year under RCP8.5, an increase of 11% in total revenues is expected. As may be seen, the changes in total revenues are not significant, because, under all scenarios, a loss in one crop is compensated by a gain in another crop. Although the overall agricultural economy of the country is not expected to be affected much, the farmers as well as the government should take action to increase the resilience of the agricultural sector, with a special focus on those crops and areas that are expected to be adversely affected by climate change impacts.
Following, the expected changes in total revenues for each crop based on the two main climatic scenarios are presented (
Table 14). The results show that all crops except potatoes present a decrease in revenues in both climatic scenarios. However, the increase in potatoes compensates to a great extent the losses in the other crops and, therefore, the estimated overall reduction in total revenues is relatively small. In the case of RCP4.5, the great losses expected for tomatoes are compensated by the gains in revenues from the increased production of potatoes. In the case of RCP8.5, production of potatoes is even higher, thus compensating for additional losses in the other crops as well.
The results of the economic assessment are in line with the results of the impact assessment, as data on crop yield and revenues have been taken into account in both cases. Slight differences between the results of the assessments may be attributed to the differentiation of the specific social characteristics of the areas where the crops are cultivated, such as in the case of grapes and barley. For example, on the basis of RCP4.5, grapes are ranked third in the impact assessment and fourth in economic losses, while the opposite is true for barley. This may be attributed to the fact that grapes are cultivated in mountain areas where the age of the population and the dependence on agriculture is high, and thus it was assigned with a highest social vulnerability score.