• Develop method for impact assessment of climate change on water quality in the watershed using a combination of hydrological and water quality models;
• Application of the method for impact assessment of climate change on water quality in upstream part of Cau River basins within two provinces Bac Kan and Thai Nguyen;
• Recommend measures to mitigate the impact of climate change on water quality in Cau River basin.

• Development of a method for assessment of climate change impacts on water quality in a river basin. The method comprises the following steps: (1) Select and develop climate change scenarios; (2) Selection of simulation models; (3) Collect data and validate the models for the study area; (4) Select the base year or year of reference; (5) Prepare appropriate data files of climate change parameters; (6) Run the model and assess the impact of climate change by comparing simulation results with the results of the base year.
• Update the GIBSI model based on new data collected (2009-2013). Applying the model to assess the impact of climate change on water quality in upstream areas of Cau River basin. The main conclusions are drawn as follows: (1) Climate change has impacted more to change the seasonal parameters of water quality than altering the annual average value. The change is greater with the higher emission scenario; (2) The change rate for wet years is less than for dry year; (3) The DO and BOD load decreased in almost all parts of the Cau River Basin; (4) Total load NH₃ increased in all parts of the basin; (6) The impact of climate change on water quality in the study area is important (the biggest changes up to 40%), climate change factors can not be ignored in the research for aquatic environment protection.
• Based on the study results, a number of adaptation measures to reduce the impact of climate change on water quality were studied and propose for application in research areas include solutions for socio-economic development, the management solutions and technology solutions.

• Development of a method for assessment of climate change impacts on water quality in river basin using a combination of simulation models, with the features: flexibility; model test criteria and the implementation steps; suitable to Vietnam's conditions.
• Assessing the impact of climate change on river water quality in Cau River basin based on emission scenarios B1, B2 and A2: some quantitative and qualitative (tendency) on the water quality changes due to climate change are obtained.
• Indicating that climate change impact on water quality is important and climate change factors can not be ignored in the task of protecting the water environment.

• Scientific papers:

1. Tran Thi Huong, Ha Ngoc Hien. Calibration of water quality model of GIBSI sofware in Cau River basin between 2009-2012. Proceedings of National Conference on Engineering Mechanics, Vol. 1, pp. 325-330, ISBN 978-604-913-2339, 4/2014.
2. Ha Ngoc Hien, Dao Thi Thu Huong. Study of the climate change impacts on water quality in upstream part of Cau river basin. Proccedings of The 14th Asia Congress of Fluid Mechanics, pp. 640-645, ISBN: 978-604-913-145-5, Oct. 2013.
3. Ha Ngoc Hien et al.. Study of the climate change impacts on water quality in upstream portion of the Cau River Basin, Vietnam. Environmental Modeling and Assessment DOI 10.1007/s10666-015-9476-0. ISSN 1420-2026, accepted 14-06-2015.
4. Pham Thi Thu Ha, Ha Ngoc Hien, Duong Ngoc Bach. Forecast and evaluate the impacts of population and domestic wastewater on water quality upstream Cau River basin by the support of a integrated informatic system. Procedding of National conference on Fluid Mechanics Binh Thuan, July 2014, pp. 200-207, ISSN: 1859-4182, 2015.
5. Pham Thi Thu Ha et al.. Assessing and selecting interventions for river water quality improvement within the context of population growth and urbanization: A case study of the Cau River Basin in Vietnam. 2015 (submitted).

• Technological products (description, store place): Software GIBSI validated for the upper part of Cau River basin. The software is stored at the Institute of Environmental Technology, VAST.
• Other products: Master student graduated in 2014 at the University of Natural Sciences, National University of Hanoi with the topic "Applying the model GIBSI for assessment of water quality in upstream portion of Cau River basin in the context of climate change".

Cau River basin, Thai Nguyen, Bac Kan provinces and other watersheds.

Applying the method to other river basins in Vietnam; Using the model to assess the effectiveness of adaptation measures in the study area.