Systemic Risk in Global Agricultural Markets and Trade Liberalization under Climate Change: Synchronized Crop-Yield Change and Agricultural Price Volatility

Climate change will increase simultaneous crop failures or too abundant harvests, creating global synchronized yield change (SYC), and may decrease stability in the portfolio of food supply sources in agricultural trade. This study evaluated the influence of SYC on the global agricultural market and trade liberalization. The analysis employed a global computable general equilibrium model combined with crop models of four major grains (i.e., rice, wheat, maize, and soybeans), based on predictions of five global climate models. Simulation results show that (1) the SYC structure was statistically robust among countries and four crops, and will be enhanced by climate change, (2) such synchronicity increased the agricultural price volatility and lowered social welfare levels more than expected in the random disturbance (non-SYC) case, and (3) trade liberalization benefited both food-importing and exporting regions, but such effects were degraded by SYC. These outcomes were due to synchronicity in crop-yield change and its ranges enhanced by future climate change. Thus, SYC is a cause of systemic risk to food security and must be considered in designing agricultural trade policies and insurance systems.

Mid-Term Impact of Climate Change on Hazelnut Yield

The impacts of climate change on hazelnut production in Turkey—the world’s largest producer and exporter—may significantly affect the global hazelnut market depending on production and yield change. In this paper, based on gridded climate data with a 10-km horizontal resolution from regional climate model RegCM4.4 under the RCP8.5 business-as-usual scenario, multiple regression analysis was conducted to investigate yield change for the period of 2021–2050. We examined a total of 88 different locations and three phenological growth stages. We observed that hazelnut yield exhibits considerable variability depending on the phenological and sub-regional and the microclimate conditions in the humid-temperate Black Sea and the semi-humid Marmara regions. Until the middle of the century, we project that hazelnut yield will decrease up to 13% in approximately half of the current production areas. In addition, the fact that the majority of the decreases will be observed in the eastern Black Sea sub-region will cause hazelnut quality to be adversely affected. These findings are highly relevant in the context of regional development and trade in Turkey, and hazelnut processing and manufacturing sectors abroad.

GLOBAL MARKET AND ECONOMIC WELFARE IMPLICATIONS OF CHANGES IN AGRICULTURAL YIELDS DUE TO CLIMATE CHANGE

The economic welfare effects of climate change on global agriculture will be mediated by several complex biophysical and economic processes. For a given emissions scenario, these include: (1) the response of the climate system to anthropogenic forcing, (2) the response of crop yields to climate system and carbon dioxide changes, given baseline improvements in crop yields, (3) the response of agricultural markets to crop yield changes, and (4) the economic welfare implications of such market responses. In this paper, we use information about the first two processes from available climate-crop model comparison studies to analyze implications for the third and fourth processes. Applying the range of crop yield changes in a Global Integrated Assessment Model (GCAM) highlights several important economic relationships. First, we find a consistent relationship between global cropland area and yield change that is approximately orthogonal to the relationship between regional cropland area and yield change. Second, we find that the change in economic welfare, expressed as total surplus change per unit economic output, peaks during the 21st century. Third, we find that, at the global level, changes in yield affect both producer surplus and consumer surplus. Specifically, surplus changes to producers and consumers are always opposite in sign, although which economic actors gain or lose varies with the sign of yield change for any given commodity. Taken together, these results contribute to a growing body of research on climate-induced changes on agriculture by highlighting several economic relationships that are robust to differences in the underlying biophysical responses.

A comparative estimate of climate change impacts on cotton and maize in Greece

The impact of climate change on cotton and maize was estimated on the basis of three IPCC Emission Scenarios (A1B, A2, B2) for seven main agronomic areas during three periods, 1961–1990, 2021–2050 and 2071–2100. All climate models were assessed for their ability to identify the yield differences through the standardized discriminant function coefficients. Discriminant analysis was performed for each period. For cotton, using the A1B scenario, areas of Western Greece exhibited the most favourable results in terms of yield increase, compared to other regions, ranging up to the maximum value of +24%. This tendency became more pronounced towards the end of the century reaching an increase of +31%. In the A2 scenario, all the areas had a positive impact on their yield change rising up to 30% in areas of central Greece. A positive change for all regions was observed for scenario B2 ranging from +10% to +25%. In maize, the scenario A1B produced small changes in yields, not exceeding 5%. For A2 scenario, yield change varied from −5.7% to +3.6%. Scenario B2 gave more optimistic estimates of yield changes towards the end of the century, in some cases exceeding 5%.

Shortened dry period in dairy Buffaloes: Influence on milk yield, milk components and reproductive performance

The objective of the present study was to determine the effect of the duration of the dry period (DP) on milk yield, milk composition, and reproductive performance of Murrah buffaloes in the subsequent lactation. High yielding Murrah buffaloes (n=48) were assigned to either shortened (30 to 45 d (n=16); and 45 to 60 d (n=16)) or traditional (>60 days (n=16)) dry period lengths. The buffaloes were fed individually according to the production status. The buffaloes in >60, 45 and 30 d dry period groups had similar (P>0.05) milk yield, 6% Fat corrected milk (FCM), milk fat, and total solids; however, the former groups had an increased (P less then 0.05) 6% FCM yield change, and SNF percentage of milk. The mean service period (days) was least (P less then0.05) with the higher number of services required for conception in buffaloes allocated to traditional dry period length compared to those assigned to shortened dry periods. Further, 6% FCM had a negative correlation with Serum Glucose (SG) values at 30 d postpartum, followed by a significant positive (P less then 0.01) correlation at 60 or 90 d postpartum. It is concluded that extended DP of more than 60 days is not advantageous and would be a costly affair for the farmers in both productive and reproductive backdrop.