In coming decades, warmer winters are likely to ease range constraints on many cold-limited forest insects^1,2,3,4,5. Recent unprecedented expansion of the southern pine beetle (SPB, Dendroctonus frontalis) into New Jersey, New York and Connecticut in concert with warming annual temperature minima highlights the risk that this insect pest poses to the pine forests of the northern United States and Canada under continued climate change⁶. Here we present projections of northward expansion in SPB-suitable climates using a statistical bioclimatic range modelling approach and current-generation general circulation model output under Representative Concentration Pathways 4.5 and 8.5. Results show that by the middle of the twenty-first century, the climate is likely to be suitable for SPB expansion into vast areas of previously unaffected forests throughout the northeastern United States and into southeastern Canada. This scenario would pose a significant economic and ecological risk to the affected regions, including disruption of local ecosystem services⁷, shifts in forest structure⁸, and threats to native biodiversity⁹.

在未来的几十年中，较温暖的冬天可能会减轻许多寒冷的森林昆虫^1,2,3,4,5的射程限制。南部松甲虫（SPB，Dendroctonus frontalis）近来史无前例地扩展到新泽西州，纽约州和康涅狄格州，并伴随着年度最低温度升高，突显了这种虫害对美国北部和加拿大的松树林造成的风险。气候变化⁶。在这里，我们使用代表性的生物气候范围模拟方法和具有代表性的浓度途径4.5和8.5下的当前代一般环流模型输出，提出了在SPB适宜的气候中向北扩张的预测。结果表明，到21世纪中叶，这种气候可能适合SPB扩展到美国东北部和加拿大东南部以前未受影响的森林的广大地区。这种情况将给受灾地区带来重大的经济和生态风险，包括当地生态系统服务的中断⁷，森林结构的变化⁸以及对当地生物多样性的威胁⁹。