USING REMOTE SENSING & MODELING FOR EVALUATING HYDROLOGIC FLUXES, STATES, & CONSTITUENT TRANSPORT PROCESSES WITHIN AGRICULTURAL LANDSCAPES
Title: Building climate resilience in the Blue Nile/Abay Highlands: Part II-arole for earth system sciences
Submitted to: International Journal of Environmental Research and Public Health
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 21, 2012
Publication Date: January 30, 2012
Citation: Zaitchik, B.F., Simane, B., Habib, S., Anderson, M.C., Ozdogan, M., Foltz, J.D. 2012. Building climate resilience in the Blue Nile/Abay Highlands: Part II-arole for earth system sciences. International Journal of Environmental Research and Public Health. 9:435-461.
Interpretive Summary: The Highlands area in Ethiopia surround the headwaters of the Blue Nile (Abay) and Atabara rivers, which provide 86% of the water to the River Nile when it joins with the White Nile in Khartoum. Water quantity and quality issues in the Abay region therefore impact water resources in many downstream riparian countries. The subsistence farming system that has developed in the Abay Highlands is highly sensitive to climate extremes, both flooding and drought. In addition, erosion stemming from agricultural practices is delivering an ever increasing load of sediment down the Blue Nile, with ramifications both for local soil tilth and sedimentation of dams downstream. Strategies for addressing these dual challenges of building climate resilience and reducing land degradation will be benefited by development of relevant Earth System Science (ESS) information datastreams, providing real-time regional climate and hydrologic information. Importantly, these datastreams must also include information regarding uncertainties in future conditions, relating to climate change. Both baseline and uncertainty data are critical for developing effective adaptive strategies. This paper summarizes several ESS data products that might be valuable for the Abay region, including satellite-based landscape classification and erosion monitoring, downscaled precipitation forecasts, and satellite-based evapotranspiration maps. Importantly, if these datastreams are to have a lasting impact on climate adaptation, ESS studies of climate impacts and climate resilience options must be nested in an interdisciplinary, multi-stakeholder conversation on climate adaptation options.
The Blue Nile (Abay) Highlands of Ethiopia are characterized by significant interannual climate variability, dissected topography and associated local climate contrasts, erosive rains and erodible soils, and intense land pressure due to an increasing population and an economy that is almost entirely dependent on smallholder, low-input agriculture. As a result, these highland zones are highly vulnerable to negative impacts of climate variability. As patterns of variability and precipitation intensity alter under anthropogenic climate change, there is concern that this vulnerability will increase, threatening economic development and food security in the region. In order to overcome these challenges and to enhance sustainable development in the context of climate change, it is necessary to establish climate resilient development strategies that are informed by best-available Earth System Science (ESS) information. This requirement is complicated by the fact that climate projections for the Abay Highlands contain significant and perhaps irreducible uncertainties. A critical challenge for ESS, then, is to generate and to communicate meaningful information for climate resilient development in the context of a highly uncertain climate forecast. Here we report on a framework for applying ESS to climate resilient development in the Abay Highlands, with a focus on the challenge of reducing land degradation. A companion paper addresses methods to incorporate this information into community-based resilience strategies.