Weng et al. (2025) Widespread land surface cooling from paddy rice cultivation revealed by global satellite mapping

Identification

Journal: Nature Communications
Year: 2025
Date: 2025-12-13
Authors: Wei Weng, Jingfeng Huang, Chao Yue, Zhenhao Lyu, Yuanjun Xiao, Shengcheng Li, Ran Huang, Chao Huang, Florent Bigirimana, Li Liu, Weiwei Liu
DOI: 10.1038/s41467-025-67549-z

Research Groups

State Key Laboratory of Soil Pollution Control and Safety, Zhejiang University, Hangzhou, China
Key Laboratory of Environmental Remediation and Ecological Health, Ministry of Education, Zhejiang University, Hangzhou, China
Institute of Applied Remote Sensing and Information Technology, Zhejiang University, Hangzhou, China
College of Natural Resources and Environment, Northwest A&F University, Yangling, China
State Key Laboratory of Soil and Water Conservation and Desertification Control, Northwest A&F University, Yangling, China
Institute of Soil and Water Conservation, Northwest A&F University, Yangling, China
School of Automation, Hangzhou Dianzi University, Hangzhou, China
Key Laboratory of Digital Earth Science, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing, China
Key Laboratory of National Forestry and Grassland Administration on Forest Ecosystem Protection and Restoration of Poyang Lake Watershed, College of Forestry, Jiangxi Agricultural University, Nanchang, China
National Institute of Statistics of Rwanda, Kigali, Rwanda
College of Computer and Information Technology, China Three Gorges University, Yichang, Hubei, China
Department of Geography and Spatial Information Techniques, Ningbo University, Ningbo, China

Short Summary

This study developed a global, long-term, high-resolution paddy rice dataset (GlobalRice500) and revealed that paddy rice cultivation significantly cools the land surface, reducing daytime land surface temperature by 0.21–0.27 °C during the growing season compared to other croplands.

Objective

To develop a universal rice mapping framework to construct a global, long-term, high-resolution paddy rice dataset (GlobalRice500).
To quantify and characterize the biophysical cooling effect of paddy rice cultivation on land surface temperature globally.

Study Configuration

Spatial Scale: Global coverage; 500 m spatial resolution for GlobalRice500; 1 km LST data resampled to 500 m; analysis performed on 10 km × 10 km grids.
Temporal Scale: GlobalRice500 covers 2001–2022 with daily temporal resolution; satellite imagery (MODIS) from 2000–2023; LST data from 2003–2020; cooling effect analyzed as annual mean during 2003–2020 and seasonal variations during the rice growing season.

Methodology and Data

Models used: Moving Phenological Detection and Dynamic Time Warping (MPD_DTW) framework; Savitzky-Golay filter; linear interpolation; block bootstrap; Student’s t-test.
Data sources: Moderate Resolution Imaging Spectroradiometer (MODIS) surface reflectance products (MOD09A1, MYD09A1) for Normalized Difference Vegetation Index (NDVI) and Land Surface Water Index (LSWI); Land Cover (LC) Products (IGBP, GlobeLand30, Crop Data Layer (CDL)); global seamless 1 km daily land surface temperature (LST) dataset (2003–2020); Global Version Elevation (GVE) Digital Elevation Model (DEM) dataset; local-scale high-resolution reference rice maps; Food and Agriculture Organization of the United Nations (FAO) country-level statistics.

Main Results

The GlobalRice500 dataset was developed, providing global-scale, long-term (2001–2022), daily temporal, and 500 m spatial resolution data on rice planting area.
Global rice area exhibited a fluctuating upward trend from 2001 to 2022, expanding by over 21 million hectares, with Asia accounting for more than 85% and Africa showing the fastest growth.
GlobalRice500 demonstrated overall accuracies typically exceeding 90% in reference regions and high consistency with FAO country-level statistics (R-squared of 0.98 for 113 countries).
Paddy rice cultivation exerts a widespread cooling effect, reducing global mean daytime land surface temperature by 0.21 (±0.0057) °C to 0.27 (±0.0063) °C during the growing season (2003–2020) compared to non-paddy croplands.
Nighttime cooling effects were negligible, with ΔLST values close to zero.
Daytime ΔLST showed an inverted V-shaped seasonal pattern, peaking around Day of Season (DOS) 60–100, corresponding to the peak growth stage.
Stronger cooling effects were observed in regions with higher paddy proportions, with ΔLST increasing by approximately 0.0014 °C for every 1% increase in paddy proportion.
Larger paddy fields exhibited stronger cooling, with maximum ΔLST increasing from 0.18 (±0.0032) °C for 1x1 pixel fields to 0.69 (±0.042) °C for 11x11 pixel fields.
The cooling effect extends beyond paddy field boundaries, spilling over into surrounding non-paddy areas, with closer areas experiencing greater cooling.

Contributions

Developed the first global, long-term (2001–2022), daily temporal, and moderate spatial resolution (500 m) paddy rice dataset (GlobalRice500), addressing a critical data gap in global rice distribution.
Introduced a novel universal rice mapping framework (MPD_DTW) that integrates phenology-based and curve-matching methods, enabling accurate identification of rice with arbitrary growth durations and intensities across diverse agro-climatic regions.
Provided the first global assessment and quantification of the biophysical cooling effect of paddy rice cultivation on land surface temperature, revealing a significant and widespread cooling of 0.21–0.27 °C during the growing season.
Characterized the spatial and temporal patterns of this cooling effect, including its relationship with paddy proportion, field size, and spillover to surrounding landscapes.
Offers a more comprehensive understanding of paddy rice's role in global climate regulation, complementing existing knowledge on its greenhouse gas emissions and informing climate-responsive agricultural strategies.

Funding

National Natural Science Foundation of China (No. 42171314)
National Key Research and Development Program (No. 2023YFD2300300)

Citation

@article{Weng2025Widespread,
  author = {Weng, Wei and Huang, Jingfeng and Yue, Chao and Lyu, Zhenhao and Xiao, Yuanjun and Li, Shengcheng and Huang, Ran and Peng, Dailiang and Huang, Chao and Bigirimana, Florent and Liu, Li and Liu, Weiwei},
  title = {Widespread land surface cooling from paddy rice cultivation revealed by global satellite mapping},
  journal = {Nature Communications},
  year = {2025},
  doi = {10.1038/s41467-025-67549-z},
  url = {https://doi.org/10.1038/s41467-025-67549-z}
}

Original Source: https://doi.org/10.1038/s41467-025-67549-z