Following on from the 47th New Phytologist Symposium - Extreme Heat: extending the thermal limits of life, we had a lively discussion covering keys insights from the several areas:

Heat and drought are inseparable.
Rising temperatures increase atmospheric water demand (vapour pressure deficit), reducing plant growth and crop yields even when soil moisture is adequate. Multiple speakers highlighted this interaction as one of the most underappreciated pressures on both crops and ecosystems.

Reproductive stages are the most vulnerable.
An extreme heat event during pollination can cause near-complete crop failure. Pollen sensitivity also emerged as one of the most useful early warning signals of ecosystem stress - detectable well before broader system failure.

Understanding heat requires thinking across scales.
From mitochondrial function to continental forest dieback, the panel emphasised that individual traits and siloed disciplines cannot deliver the predictive power we need. A systems approach - connecting molecular biology, ecology, remote sensing and social science - is now essential.

Society faces hard choices.
From developing heat-tolerant wheat varieties to managing alpine ecosystems such as the snow gum woodlands that support Australia’s irrigation zones, scientists can map the available options. However, decisions on gene editing, assisted species migration and water allocation ultimately sit with communities and these conversations need to start now.

A global research community is forming.
The Córdoba symposium brought together 150 researchers from 29 countries. One key outcome was a proposal to establish coordinated global heatwave monitoring hubs to track and measure El Niño’s impacts in real time, strengthening the evidence base for solutions. We look forward to seeing how this progresses over the next 12 months. 

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