Global Forests Show Stronger Temperature Regulation

A global analysis of satellite data reveals that forests have significantly strengthened their capacity to regulate land surface temperature over the past two decades. Published in Nature Plants, the study provides evidence that this ecosystem-scale surface thermal regulation capacity, or TRC, has evolved in a way that mitigates climate warming. The research team utilized twenty years of satellite-based observations, spanning from 2001 to 2020, to assess how forest ecosystems interact with local air temperatures.

The study identifies two primary metrics to quantify the enhancement of forest temperature regulation. First, the slope between land surface temperature and air temperature, denoted as beta, showed a widespread decline of 0.0014 plus or minus 0.0003 degrees Celsius per degree Celsius per year. Second, the difference between land surface temperature and air temperature, denoted as delta T, decreased by 0.0268 plus or minus 0.005 degrees Celsius per year. Both trends were statistically significant, with P-values less than 0.01, indicating that forests are becoming more effective at buffering surface temperatures against rising air temperatures.

The observed enhancement in thermal regulation capacity is primarily associated with two key environmental factors: increased tree cover and ongoing warming trends.

Species richness emerges as a significant factor in determining the magnitude of temperature regulation. The analysis found that species-rich forests exhibit higher thermal regulation capacity compared to less diverse forests. This effect is likely mediated through an enhanced ratio of transpiration to evapotranspiration.

Furthermore, the study reveals that spatial and temporal variations in thermal regulation capacity covary with the optimal temperature for forest photosynthesis.

The research also links thermal regulation capacity to photosynthetic resistance to thermal stress.

The findings underscore the critical importance of conserving and restoring diverse forests to regulate surface energy balance.

Subject of Research: Enhanced forest temperature regulation covaries with greater heat resistance of ecosystem photosynthesis

Article Title: Enhanced forest temperature regulation covaries with greater heat resistance of ecosystem photosynthesis

Article References: Cao, R., Zhang, Y., Fernández-Martínez, M., Descals, A., Sardans, J., & Peñuelas, J. (2026). Enhanced forest temperature regulation covaries with greater heat resistance of ecosystem photosynthesis. Nature Plants. https://doi.org/10.1038/s41477-026-02453-y

Image Credits: AI Generated

DOI: 10.1038/s41477-026-02453-y

Keywords: Enhanced, forest, temperature, regulation, covaries, greater, heat, resistance, ecosystem, photosynthesis, scientific research