Risk of Climate-Related Impacts on Global Rangelands – A Review and Modelling Study

Climate change threatens the ability of global rangelands to provide food, support livelihoods and deliver important ecosystems services. The extent and magnitude of potential impacts are however poorly understood. In this study, we review the risk of climate impacts along the rangeland systems food supply chain. We also present results from biophysical modelling simulations and spatial data analyses to identify where and to what extent rangelands may be at climatic risk. Although a quantification of the net impacts of climate change on rangeland production systems is beyond the reach of our current understanding, there is strong evidence that there will be impacts throughout the supply chain, from feed and animal production to processing, storage, transport, retailing and human consumption. Regarding grazing biomass production, this study finds that mean herbaceous biomass is projected to decrease across global rangelands between 2000 and 2050 under RCP 8.5 (-4.7%), while inter- (year-to-year) and intra- (month-to-month) annual variabilities are projected to increase (+21.3% and +8.2%, respectively). These averaged global estimates mask large spatial heterogeneities, with 74% of global rangeland area projected to experience a decline in mean biomass, 64% an increase in inter-annual variability and 54% an increase in intra-annual variability. The potentially most damaging vegetation trends for livestock production (i.e., simultaneous decreases in mean biomass and increases in inter-annual variability) are projected to occur in rangeland communities that are currently the most vulnerable (here, with the lowest livestock productivities and economic development levels and with the highest projected increases in human population densities). Large uncertainties remain as to climate futures and the exposure and responses of the interlinked human and natural systems to climatic changes over time. Consequently, adaptation choices will need to build on robust methods of designing, implementing and evaluating detailed development pathways, and account for a wide range of possible futures

EL AFLORAMIENTO COSTERO Y EL FENÓMENO DE EL NIÑO: IMPLICACIONES SOBRE LOS RECURSOS BIOLÓGICOS DEL PACIFICO DE PANAMÁ

The Panamanian Pacific is under the influence of natural environmental changes, such as the coastal upwelling and manifestation of El Niño. These events can have severe implications for the biological resources. In this study we characterized the hydrological changes in the Gulf of Panama as related to their seasonality and annual variability. The intensity of the upwelling was assessed using sea surface temperature data. We also evaluated the coral genetic diversity for the coral Pocillopora damicornis. There were obvious changes in the hydrological and biological parameters monitored in the Gulf of Panama as result of the upwelling. The historical analysis of upwelling in the Gulf of Panama indicated that the upwelling occurs in pulses related to sea surface temperatures. In conclusion, sea surface temperature is the best quantitative estimate of upwelling intensity in the Gulf of Panama. The electrophoretic analysis of isozymes in the coral Pocillopora damicornis in Panama suggest the existence of a wider genetic diversity in the thermically stable water of the Gulf of Chiriquí and in areas of moderate upwelling such as Iguana Island in the Gulf of Panama. This contrast with the limited genotypic diversity found in areas of strong upwelling such as the Pearl Islands and the Panama Bay.  La costa del Pacífico panameño está bajo la influencia de cambios ambientales naturales, como el afloramiento costero y las manifestaciones del fenómeno de El Niño, que tienen implicaciones sobre los recursos biológicos. Durante este estudio se caracterizaron las variaciones hidrológicas estacionales e interanuales en el Golfo de Panamá, se estimó la intensidad del afloramiento utilizando los datos de la temperatura superficial del mar y se evaluó preliminarmente la diversidad genotípica de los corales. Se observaron cambios notables en la calidad del agua en el Golfo de Panamá como consecuencia del afloramiento. El análisis histórico de los afloramientos en el Golfo de Panamá indica que éstos son pulsativos y con más de dos períodos y asociados a las temperaturas superficiales del mar. La temperatura representa el mejor estimado cuantitativo de la intensidad de afloramiento periódico en el Golfo de Panamá. El análisis electroforético de las isoenzimas del coral Pocillopora damicornis en Panamá sugiere la existencia de una amplia diversidad genética en las áreas térmicamente estables del Golfo de Chiriquí y en áreas de afloramiento moderado como Isla Iguana en el Golfo de Panamá. Lo anterior contrasta con la limitada diversidad de genotipos que tiene la especie en las áreas con fuerte influencia del afloramiento, como en el Archipiélago de Las Perlas y en las islas de la Bahía de Panamá

Linking regional stakeholder scenarios and shared socioeconomic pathways: Quantified West African food and climate futures in a global context

The climate change research community’s shared socioeconomic pathways (SSPs) are a set of alternative global development scenarios focused on mitigation of and adaptation to climate change. To use these scenarios as a global context that is relevant for policy guidance at regional and national levels, they have to be connected to an exploration of drivers and challenges informed by regional expertise. In this paper, we present scenarios for West Africa developed by regional stakeholders and quantified using two global economic models, GLOBIOM and IMPACT, in interaction with stakeholder-generated narratives and scenario trends and SSP assumptions. We present this process as an example of linking comparable scenarios across levels to increase coherence with global contexts, while presenting insights about the future of agriculture and food security under a range of future drivers including climate change. In these scenarios, strong economic development increases food security and agricultural development. The latter increases crop and livestock productivity leading to an expansion of agricultural area within the region while reducing the land expansion burden elsewhere. In the context of a global economy, West Africa remains a large consumer and producer of a selection of commodities. However, the growth in population coupled with rising incomes leads to increases in the region’s imports. For West Africa, climate change is projected to have negative effects on both crop yields and grassland productivity, and a lack of investment may exacerbate these effects. Linking multi-stakeholder regional scenarios to the global SSPs ensures scenarios that are regionally appropriate and useful for policy development as evidenced in the case study, while allowing for a critical link to global contexts

Interpreting the Shared Socio-economic Pathways under Climate Change for the ECOWAS region through a stakeholder and multi-model process

The IPCC community’s Shared Socio-economic Pathways (SSPs) are a set of alternative global development futures focused on drivers of challenges to mitigation of and adaptation to climate change. However, the impacts and drivers of plausible future development at any national or regional level have yet to be examined for consistency within the global narrative. In this paper, we present four globally-consistent regional scenarios on Western Africa’s development that have been used to test and develop a range of national and regional policies. The regional scenarios were outlined independently by regional stakeholders but built around the context of the SSPs. The scenarios were quantified using two agricultural models, GLOBIOM and IMPACT, in interaction with drivers outlined by the SSPs and guided by semi-quantitative information from the stakeholders. Our paper 1) demonstrates how linkages of global SSPs and regional multi-stakeholder scenarios can be achieved through a process of critical comparison, starting from regional priorities, to produce consistent scenarios for future regional development; 2) provides insights for Western Africa on the future of development, agriculture, food security and climate impacts in both qualitative and quantitative scenarios; 3) reports on a set of scalable scenarios for regional decision makers and the scientific community to use to build and test robust agriculture and climate policies

Can sub-Saharan Africa feed itself?

Although global food demand is expected to increase 60% by 2050 compared with 2005/2007, the rise will be much greater in sub-Saharan Africa (SSA). Indeed, SSA is the region at greatest food security risk because by 2050 its population will increase 2.5-fold and demand for cereals approximately triple, whereas current levels of cereal consumption already depend on substantial imports. At issue is whether SSA can meet this vast increase in cereal demand without greater reliance on cereal imports or major expansion of agricultural area and associated biodiversity loss and greenhouse gas emissions. Recent studies indicate that the global increase in food demand by 2050 can be met through closing the gap between current farm yield and yield potential on existing cropland. Here, however, we estimate it will not be feasible to meet future SSA cereal demand on existing production area by yield gap closure alone. Our agronomically robust yield gap analysis for 10 countries in SSA using location-specific data and a spatial upscaling approach reveals that, in addition to yield gap closure, other more complex and uncertain components of intensification are also needed, i.e., increasing cropping intensity (the number of crops grown per 12 mo on the same field) and sustainable expansion of irrigated production area. If intensification is not successful and massive cropland land expansion is to be avoided, SSA will depend much more on imports of cereals than it does today