Introduction In Central Asia, the management of transboundary river basins, particularly under the pressures of climate change, has become challenging, with implications for regional prosperity and sustainable development. An important international river in Central Asia, the Irtysh River extends 4,248 kilometers and flows through the People’s Republic of China (PRC), Kazakhstan, and Russia. The river basin covers an area of about 165×104 km2, supporting around 15 million people. As existing research primarily focuses on its hydrological aspects, there is a critical gap in understanding the complex interactions between water, food, energy, and climate. Most analyses remain confined to local or national perspectives, overlooking the potential of basin-wide strategies through transboundary cooperation. Recognizing this gap, a study conducted under the Central Asia Regional Economic Cooperation (CAREC)[1] Institute explores the transboundary cooperation in the water-food-energy nexus, with a focus on the Irtysh River Basin. It seeks to identify adaptive management strategies that can enhance resilience to climate change, improve regional cooperation, and ensure more efficient and equitable resource allocation across the borders. By establishing clear system of boundaries and integrating diverse datasets, this study employs a two-step approach—climate modeling and regional comparative analysis—that advances interdisciplinary research to provide policymakers with actionable insights. Trends of Climate Change Across the Basin Our analysis of 20 years of hydrological data reveals temporal heterogeneity in water flows across eight Irtysh River Basin sub-basins, with downstream sub-basins experiencing greater water scarcity. Additionally, temperature trends show an average increase of 0.65°C since 2000, with the most significant warming observed in the upstream sub-basins. The drought conditions in 2022 and 2023 further emphasized the basin’s vulnerability to climate change. Moreover, based on 288 samples of monthly climatic data between 2000 and 2023, the regression model results reveal spatial variations of climatic variables, which indicate that decreased precipitation likely reduces river discharge. Comparison of Regional Water-Food-Energy Nexus For regional comparative analysis, the core study sites of the Irtysh River Basin are the Altay region in Northwest PRC (upstream) and East Kazakhstan province (downstream) because of their shared and complementary hydrological characteristics. Results highlight varied regional responses to climate change. Upstream in the Altay region in Xinjiang province, food production rapidly grew from 2007 to 2018. However, adapting to a drier climate and improving water use efficiency prompted a shift in crop patterns toward less water-intensive crops, supported by strict water resource management regulations and enhanced irrigation systems. Additionally, this region diversified its energy mix, significantly increasing the share of wind and solar power, while decreasing reliance on hydropower. Downstream in East Kazakhstan, agriculture showed a slight diversification, although it remained vulnerable to weather variability. Water losses in irrigation systems are severe in the water sector, while the adoption of water-saving technologies remains low and particularly difficult among smallholder farmers. Furthermore, this region’s energy production continued to rely on hydropower, while solar and wind energy remain underutilized. Mechanisms for Transboundary Cooperation Effective transboundary cooperation relies on mutual trust, robust institutional frameworks, collaborative planning, and fairly sharing ecological and socio-economic benefits and costs. Some existing mechanisms can provide valuable experiences and lessons for enhancing transboundary cooperation: Market-based mechanisms Payments for ecosystem services: This approach incentivizes ecological protection by enabling downstream beneficiaries to compensate upstream communities for conservation efforts. EU Water, Energy, and Food Management Policies: The EU promotes inclusive water management through intergovernmental water commissions, ensuring equitable management among riparian states. Integrated River Basin Management: This framework facilitates regional collaboration and knowledge exchange, enabling information sharing to support sustainable basin management across multiple stakeholders. Belt and Road InitiativePRC has developed a strategic framework for transboundary water management in Central Asia. It leverages existing international water cooperation mechanisms to promote economic benefits through sustainable management of shared water resources. Cross-regional water resources governanceThe River Chief System is an innovative water governance framework originally developed in PRC’s river basin management. It breaks through traditional water resource management models, leveraging the authority and resources of higher-level governments to overcome regional barriers. National water policy in agricultureLow agricultural water tariffs lead to inefficient water use both in PRC and Kazakhstan. Barriers such as inadequate technical services, weak operational management, and insufficient financial support hinder the adoption of water-saving irrigation practices. PRC’s "Pilot Implementation for Water Resource Tax Reform" will levy taxes based on the volume of water extracted, with differentiated tax rates depending on water scarcity conditions, the type of water usage, and level of economic development. Meanwhile, Kazakhstan’s New Water Code aims to establish a comprehensive national policy for saving water. Implementation Challenges Despite policy efforts, transboundary cooperation in the Water-Food-Energy nexus faces significant challenges related to data sharing and institutional mechanisms. Limited access to government-held data restricts in-depth research on transboundary issues. In Kazakhstan, water sector data remains scarce, with no publicly accessible database. Also, Kazakhstan’s recent agricultural reforms need support in terms of technology dissemination, funding, and policy incentives. Kazakhstan’s commitment to the National 2050 Low Carbon Energy Strategy require further analysis of how new energy policies may impact water resource utilization. Policy Implications Building on the experiences and challenges in transboundary water, food, and energy cooperation, strengthened collaboration between PRC and Kazakhstan, as upstream and downstream countries, can enhance climate adaptation, promote sustainable water management, and support border economic development. The following policy actions are recommended: Enhance water-saving technologies. PRC can leverage its technological advantages in water resource management to assist downstream regions in upgrading irrigation systems and adopting water-saving technologies, especially for smallholder farmers. Promote green energy investments. PRC can expand its technological investments in Kazakhstan, improving infrastructure and fostering technological innovations in green energy to support Kazakhstan's structural transformation. Deepen agricultural trade. Kazakhstan is actively exploring international markets for high-quality agricultural products. PRC can deepen its cooperation with Kazakhstan in agricultural trade as aligned with agricultural modernization program and industrial expertise. Establish a data-sharing platform. To improve transboundary basin management, both countries can develop a data-sharing mechanism, ensuring transparency and accessibility of water, agriculture, and energy sector data between upstream and downstream stakeholders. [1] CAREC is composed of Afghanistan, Azerbaijan, People’s Republic of China, Georgia, Kazakhstan, Kyrgyz Republic, Mongolia, Pakistan, Tajikistan, Turkmenistan, and Uzbekistan. Resources X. Wang et al. 2025. Transboundary Cooperation in the Water-Food-Energy Nexus: Adapting to a Changing Climate. Policy Brief. Central Asia Regional Economic Cooperation (CAREC) Institute. X. Wang et al. 2025. Water-Food-Energy Nexus: Transboundary Cooperation under Climate Change. CAREC Institute. Ask the Experts Xialin Wang Research Fellow, Institute of International Rivers and Eco-security, Yunnan University Xialin Wang holds a PhD in Agricultural Economics from Justus-Liebig University Giessen, Germany and degrees in Water Resources Engineering from the People’s Republic of China. Her research focuses on developing new mechanisms to solve resource conflicts, especially in water. She specializes in interdisciplinary studies on water-food-energy nexus, climate adaptation, and transboundary basin management, with a focus on Southern Africa, Northern PRC, and Central Asia. Central Asia Regional Economic Cooperation Institute (CAREC) The Central Asia Regional Economic Cooperation Institute (CAREC) is an intergovernmental organization promoting economic cooperation in Central Asia and along the ancient Silk Road through knowledge generation and sharing. CAREC is jointly shared, owned, and governed by 11 member countries: Afghanistan, Azerbaijan, People’s Republic of China, Georgia, Kazakhstan, Kyrgyz Republic, Mongolia, Pakistan, Tajikistan, Turkmenistan, and Uzbekistan. Leave your question or comment in the section below: View the discussion thread.