{"id":236962,"date":"2026-06-08T16:12:50","date_gmt":"2026-06-08T08:12:50","guid":{"rendered":"https:\/\/www.cpr.cuhk.edu.hk\/?post_type=press&p=236962"},"modified":"2026-06-08T16:12:50","modified_gmt":"2026-06-08T08:12:50","slug":"cuhk-led-study-first-reveals-irrigation-helps-slow-chinas-warming-findings-advance-climate-smart-water-management","status":"publish","type":"press","link":"https:\/\/www.cpr.cuhk.edu.hk\/en\/press\/cuhk-led-study-first-reveals-irrigation-helps-slow-chinas-warming-findings-advance-climate-smart-water-management\/","title":{"rendered":"CUHK-led study first reveals irrigation helps slow China\u2019s warming Findings advance climate-smart water management"},"content":{"rendered":"","protected":false},"featured_media":0,"template":"","tags":[],"class_list":["post-236962","press","type-press","status-publish","hentry"],"acf":{"title_alt":"CUHK-led study first reveals irrigation helps slow China\u2019s warming\r\nFindings advance climate-smart water management","sub_title_alt":"","press_date":"20260608","keep":false,"details":"

A research team led by The Chinese University of Hong Kong (CUHK), in collaboration with Chongqing University, The University of Hong Kong, and Lanzhou University, has for the first time identified irrigation, in addition to industrial aerosol cooling, as a crucial factor explaining why China\u2019s warming over the past half-century has been markedly slower than in most other regions of the world. The study, which provides the first quantitative assessment of irrigation\u2019s contribution to climate moderation in China, has recently been published in the leading international journal Geophysical Research Letters<\/em><\/a>.<\/em><\/p>\r\n

Irrigation<\/strong> mitigates surface warming during farming season<\/strong><\/p>\r\n

While scientists have long attributed the nation\u2019s relatively subdued warming to industrial aerosol pollution, which scatters sunlight and cools the land surface, the CUHK-led team found that aerosols alone could not explain regional differences \u2013 in particular, why the heavily irrigated North China Plain, home to more than one-third of China\u2019s irrigated cropland, has recorded unusually mild warming, despite rapid urban and industrial growth.<\/p>\r\n

By combining over 50 years of meteorological records (1961-2016) with detailed regional climate model simulations, the team discovered that irrigation expansion produced net daytime cooling of about 0.19\u00b0C per decade between 1961 and 2005 in spring (April-June), nearly offsetting greenhouse gas-driven warming.<\/p>\r\n

Professor <\/strong>Amos Tai Pui-kuen<\/strong>, the study\u2019s principal investigator from CUHK\u2019s Department of Earth and Environmental Sciences, explained: \u201cOur findings show that irrigation made a significant contribution to the slower warming in China, and helped alleviate daytime heat stress in agricultural regions. The evaporation of irrigation water acted like a powerful air conditioner that quietly countered part of the greenhouse effect, especially during the farming season.\u201d<\/p>\r\n

Since the mid-2000s, however, this cooling benefit has weakened as irrigation expansion has plateaued and water-saving techniques have become more widespread. The research model projects that, under a medium-emission scenario, continued irrigation could offset nearly half of springtime warming in northern China by\u00a02050, though its protective effect will decline if irrigation water use continues to shrink.<\/p>\r\n

From water saving to climate-smart irrigation<\/strong><\/p>\r\n

With growing water scarcity, China has been pressing ahead with water-saving irrigation to address critical challenges such as groundwater depletion, land subsidence and river drying. Professor\u202fTai emphasised that conserving water must remain a top priority \u2013 yet it brings a new climatic dilemma: less evaporative cooling may lead to heightened exposure to extreme heat.<\/p>\r\n

Dr Yuan Tiangang<\/strong>, the first author of the study and a former Postdoctoral Fellow at CUHK, said: \u201cWe cannot abandon water conservation \u2013 that would be environmentally disastrous. But we also cannot ignore that irrigation offers a climate-cooling co-benefit that relieves both water and heat stress. Smarter, integrated water-climate management will be crucial to sustaining China\u2019s food and climate security.\u201d<\/p>\r\n

Professor Li Jianfeng<\/strong>, another coauthor of the study, from CUHK\u2019s Department of Geography and Resource Management, added: \u201cWater saving doesn\u2019t have to mean climate vulnerability. By integrating precision irrigation and ecological restoration, we can deliver co-benefits among water conservation, agriculture and climate resilience.\u201d<\/p>\r\n

The study recommends adopting a multi-pronged climate-smart approach:<\/p>\r\n

    \r\n\t
  1. Precision irrigation with climate feedback<\/strong> \u2013 using real-time soil and weather data to calculate the appropriate amount of water for both efficient crop growth and local temperature moderation.<\/li>\r\n\t
  2. Enhancing soil health and vegetation cover<\/strong> \u2013 through measures such as mulching, organic amendments and cover crops, to naturally retain moisture and reinforce microclimate stability.<\/li>\r\n\t
  3. Coordinated water-climate governance<\/strong> \u2013 aligning irrigation scheduling, crop selection and energy use to reduce both water stress and thermal risk.<\/li>\r\n\t
  4. Nature-based cooling solutions<\/strong> \u2013 restoring wetlands and implementing managed aquifer recharge to recreate part of irrigation\u2019s evaporative buffering effect.<\/li>\r\n<\/ol>\r\n

    This study was funded by the Research Grants Council (Collaborative Research Fund and General Research Fund), the Innovation and Technology Fund of Hong\u202fKong and the National Natural Science Foundation of\u202fChina.<\/p>","show_as_achievement":false,"achievement_category":[],"show_as_clarification":false,"show_as_announcement":false,"photos":[{"photo":236974,"caption":"Professor Amos Tai Pui-kuen (2nd right) of CUHK\u2019s Department of Earth and Environmental Sciences, Dr Yuan Tiangang (1st right), and other team members visit an experimental field site for agricultural research in East China."},{"photo":236977,"caption":"Impacts of historical irrigation expansion on daytime temperature (\u0394Tmax) during 1961-2005 and model projected cooling effect of irrigation when keeping current irrigation extent under medium (SSP245) and high (SSP585) warming scenarios by 2050s."}],"attachments":null,"video_source":"","video_file":"","add_play_button":false,"video_caption":"","show_migration":false,"original_id":0,"photos_original":null,"attachments_original":null},"publishpress_future_workflow_manual_trigger":{"enabledWorkflows":[]},"_links":{"self":[{"href":"https:\/\/www.cpr.cuhk.edu.hk\/en\/wp-json\/wp\/v2\/press\/236962","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.cpr.cuhk.edu.hk\/en\/wp-json\/wp\/v2\/press"}],"about":[{"href":"https:\/\/www.cpr.cuhk.edu.hk\/en\/wp-json\/wp\/v2\/types\/press"}],"version-history":[{"count":15,"href":"https:\/\/www.cpr.cuhk.edu.hk\/en\/wp-json\/wp\/v2\/press\/236962\/revisions"}],"predecessor-version":[{"id":236987,"href":"https:\/\/www.cpr.cuhk.edu.hk\/en\/wp-json\/wp\/v2\/press\/236962\/revisions\/236987"}],"wp:attachment":[{"href":"https:\/\/www.cpr.cuhk.edu.hk\/en\/wp-json\/wp\/v2\/media?parent=236962"}],"wp:term":[{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.cpr.cuhk.edu.hk\/en\/wp-json\/wp\/v2\/tags?post=236962"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}