ABSTRACT Changes in growing season length (GSL) are of concern for agricultural, phenological, economic, epidemiological, and bioclimatological reasons. This research identifies spatial and temporal changes over the last several decades in GSL, along with the day-of-year of the last spring freeze and first autumn freeze, for the northeastern United States – a region particularly susceptible to such changes due to the large population and intense economic activities. Results suggest that growing season has significantly increased in length since 1980 as compared to prior to 1980, and both spatial and temporal variation in GSL has decreased for the region over time. Changes to GSL for this region are driven more by a shift in the first autumn freeze date than the last spring freeze date. The areas of greatest increase in GSL in the pre- vs. post-1980 period tend to be in the high elevations, near large water bodies, and near the largest cities. Results will assist environmental planners as they prepare mitigation and adaptation strategies amid a changing environment.

中文翻译：

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美国东北部生长季节的变化

摘要 由于农业、物候、经济、流行病学和生物气候原因，生长季长度 (GSL) 的变化受到关注。这项研究确定了过去几十年 GSL 的空间和时间变化，以及美国东北部最后一次春季冻结和第一次秋季冻结的日期——由于大人口密集，经济活动频繁。结果表明，与 1980 年之前相比，自 1980 年以来，生长季节的长度显着增加，并且该地区 GSL 的空间和时间变化随着时间的推移而减少。该地区 GSL 的变化更多是由第一个秋季冻结日期的变化而不是最后一个春季冻结日期驱动的。GSL 增加最多的区域 1980 年后的时期往往是在高海拔地区，靠近大型水体，靠近最大的城市。结果将有助于环境规划者在不断变化的环境中准备缓解和适应战略。