The updated 2025 version of the Climate Change Scenario provides climate information detailed down to the commune level, adding global warming scenarios, sea level rise inundation risks, and in-depth data for urban areas. This is an important scientific basis helping localities, businesses, and organizations proactively assess risks and build climate change adaptation plans.
Updating climate data to serve local adaptation needs
On October 9, 2026, the Ministry of Agriculture and Environment organized a conference to announce the Climate Change (CC) Scenario for Vietnam, updated 2025 version.
The new scenario inherits previous research results while updating scientific advancements from the Intergovernmental Panel on Climate Change (IPCC). A notable point is that the data not only serves national or regional scale assessments but is also detailed to the commune level, meeting the needs for planning and risk management at the local level.
According to information from the Ministry of Agriculture and Environment, the updated version comprises 8 chapters and in-depth appendices, adding contents on urban climate, global warming levels, inundation risks, and data exploitation guidelines.
Deputy Minister of Agriculture and Environment Le Trong Yen, Director of the Department of Climate Change Nguyen Tuan Quang, and Assoc. Prof. Dr. Pham Thi Thanh Nga, Director of the Vietnam Institute of Meteorology, Hydrology and Climate Change, chaired the workshop. Photo: Trung Nguyen.
Besides familiar factors such as temperature and precipitation, the scenario also provides additional information on wind, radiation, and sea surface temperature. The data is updated by decades, enabling users to examine climate changes across different periods.
Speaking at the conference, Deputy Minister of Agriculture and Environment Le Trong Yen emphasized the role of the scenario in management, policy-making, development planning, and the selection of adaptation solutions suitable to each sector, field, and locality.
Heatwaves and extreme rainfall may increase significantly
One of the new features of the 2025 Climate Change Scenario is the assessment of extreme climate phenomena corresponding to global warming levels of 1.5°C, 2°C, 3°C, and 4°C.
This approach helps clarify changes in climate phenomena as global average temperatures rise, thereby providing an additional basis for risk assessment and adaptation planning.
According to the high emission scenario, by the end of the 21st century, the number of hot days in some regions could increase by over 50 days, while the number of intense heatwave days increases by about 20 days. Conversely, the number of days with severe cold in the North and North Central region is projected to decrease sharply.
Regarding precipitation, results show an increased risk of extreme rainfall phenomena. Maximum daily and five-day rainfall in the North and South is projected to increase by about 30–40%. Notably, in some areas of the North, the Central Highlands, and the South, the number of days with rainfall exceeding 100 mm/day may increase by 80–100% under the high scenario.
These changes pose the requirement to enhance disaster risk assessment, especially for drainage systems, infrastructure, agricultural production, and areas with high exposure to extreme weather.
Developing in-depth climate scenarios for urban areas for the first time
A prominent content of the 2025 version is the development of in-depth climate scenarios for urban areas, focusing on Hanoi and Ho Chi Minh City. In large cities, the impacts of climate change can become more complex when combined with urbanization, high building density, and changes in land surface characteristics.
The new scenario simultaneously examines the impacts of global warming and urbanization, thereby clarifying the trends of increasing temperatures, heatwaves, the urban heat island effect, and extreme precipitation. This information is significant for building cities with better resilience against climate change.
For example, data on extreme temperatures and precipitation can support specialized agencies in assessing the demand for green space development, organizing drainage systems, selecting construction materials, and adjusting infrastructure planning to suit future climate conditions.
For educational institutions, industrial zones, and residential areas, accessing local-scale climate data also provides an additional basis for assessing exposure levels to heatwaves, heavy rainfall, and related risks.
Sea level rise and flood risks in coastal areas
In addition to onshore climatic factors, the 2025 updated version continues to assess sea level rise trends in the East Sea and along the coast of Vietnam.
By 2100, the average sea level rise across the East Sea is projected to be about 46.1 cm under the low scenario and 63.7 cm under the high scenario. For the entire coastal strip of Vietnam, under the high scenario, the average sea level rise by the end of the century is projected to be about 61.9 cm, with the upper bound potentially reaching 82 cm.
Flood risk maps based on sea level rise also show significant differences among geographical regions. Among them, the Mekong Delta is identified as the region with the highest flood risk. Many coastal areas in the Northern and Central regions have lower flood percentages due to differences in topographical characteristics.
Information on sea level rise and flood risks is an important basis for researching land-use planning, coastal infrastructure development, water resource management, and formulating adaptation options in vulnerable areas.
However, it should be noted that flood risk maps based on sea level rise scenarios do not equate to precise forecasts of actual flooding extents at a specific time. The level of flooding also depends on specific conditions such as topography, protective structures, land subsidence, and hydrological factors.
Climate data integrated on the WebGIS platform
Along with updating scientific content, the Ministry of Agriculture and Environment has integrated scenario data into the National Database on Climate Change.
The scenarios are provided in various formats, including full reports, executive summaries for managers, and a WebGIS system for information lookup. Through WebGIS, users can access data spatially and temporally, compare climate scenarios, review changes between periods, and exploit information suitable for research and management needs.
The application of digital mapping technology makes climate data more intuitive and convenient to use. This is also a meaningful approach for research, training, and scientific communication, as complex information on climate change can be presented in the form of maps, charts, and spatial data.
From scientific scenarios to adaptation action
Climate change scenarios are neither weather forecasts nor definitive affirmations of future climate states.
According to scientists, these are scientifically grounded assumptions about climate change trends, developed based on the relationships between socio-economic development, greenhouse gas emissions, climate change, and sea level rise. Therefore, the use of scenarios requires considering uncertainty ranges and selecting options appropriate to the assessment objectives.
Assoc. Prof. Dr. Pham Thi Thanh Nga, Director of the Institute of Hydrometeorology, Environment and Marine Science, shares about the process of developing the updated scenario. Photo: Trung Nguyen.
For building planning and design according to specific timelines, experts recommend consulting information from multiple low, medium, and high scenarios. Meanwhile, long-term risk assessment and the development of flexible adaptation pathways can utilize data based on global warming levels. The release of the updated 2025 Climate Change Scenario continues to provide a scientific information resource for responding to climate change in Vietnam.
More importantly, the value of the dataset lies not only in numbers or maps, but also in how the information is translated into concrete decisions in planning, resource management, infrastructure development, and community protection.
When climate data is appropriately harnessed and utilized, localities, organizations, and businesses will have an additional basis to proactively prepare for the risks of a changing climate.
