Warming experiments underpredict plant phenological responses to climate change.

Area of Science:

• Ecology
• Climate Change Biology
• Plant Science

Background:

• Warming experiments are crucial for predicting plant responses to global climate change.
• Accurate predictions require experimental data to reflect observed temperature variability and warming trends.

Purpose of the Study:

• To compare plant phenology (timing of life events) from warming experiments with observational studies.
• To assess the reliability of warming experiments in predicting plant responses to climate change.

Main Methods:

• Meta-analysis of observational studies and warming experiments across four continents and 1,634 plant species.
• Comparison of temperature sensitivity (days per degree Celsius) between experimental and observational data.

Main Results:

• Warming experiments significantly underpredicted advances in flowering (8.5-fold) and leafing (4.0-fold) compared to observations.
• Experimental results for common species did not match observational data in sign or magnitude.
• Observed trend of earliest flowering species having highest temperature sensitivity was absent in experimental data.

Conclusions:

• Significant mismatches exist between warming experiments and observational data on plant phenology.
• Discrepancies may stem from experimental artifacts (e.g., lower irradiance, drier soils) or complex real-world interactions.
• Current ecosystem models relying solely on experimental data may overestimate climate change impacts and require re-evaluation.