Harkness Caroline, Semenov Mikhail A, Areal Francisco, Senapati Nimai, Trnka Miroslav, Balek Jan, Bishop Jacob
School of Agriculture Policy and Development, University of Reading, Earley Gate, Reading RG6 6AH, United Kingdom.
Sustainable Agricultural Sciences, Rothamsted Research, West Common, Harpenden, Hertfordshire AL5 2JQ, United Kingdom.
Agric For Meteorol. 2020 Mar 15;282-283:107862. doi: 10.1016/j.agrformet.2019.107862.
Winter wheat is an important crop in the UK, suited to the typical weather conditions in the current climate. In a changing climate the increased frequency and severity of adverse weather events, which are often localised, are considered a major threat to wheat production. In the present study we assessed a range of adverse weather conditions, which can significantly affect yield, under current and future climates based on adverse weather indices. We analysed changes in the frequency, magnitude and spatial patterns of 10 adverse weather indices, at 25 sites across the UK, using climate scenarios from the CMIP5 ensemble of global climate models (GCMs) and two greenhouse gas emissions (RCP4.5 and RCP8.5). The future UK climate is expected to remain favourable for wheat production, with most adverse weather indicators reducing in magnitude by the mid-21st century. Hotter and drier summers would improve sowing and harvesting conditions and reduce the risk of lodging. The probability of late frosts and heat stress during reproductive and grain filling periods would likely remain small in 2050. Wetter winter and spring could cause issues with waterlogging. The severity of drought stress during reproduction would generally be lower in 2050, however localised differences suggest it is important to examine drought at a small spatial scale. Prolonged water stress does not increase considerably in the UK, as may be expected in other parts of Europe. Climate projections based on the CMIP5 ensemble reveal considerable uncertainty in the magnitude of adverse weather conditions including waterlogging, drought and water stress. The variation in adverse weather conditions due to GCMs was generally greater than between emissions scenarios. Accordingly, CMIP5 ensembles should be used in the assessment of adverse weather conditions for crop production to indicate the full range of possible impacts, which a limited number of GCMs may not provide.
冬小麦是英国的一种重要作物，适合当前气候条件下的典型天气状况。在气候变化的背景下，不利天气事件（通常具有局部性）的频率和强度增加，被认为是小麦生产的主要威胁。在本研究中，我们基于不利天气指数，评估了一系列在当前和未来气候条件下可能显著影响产量的不利天气状况。我们利用全球气候模型（GCM）的CMIP5集合中的气候情景以及两种温室气体排放情景（RCP4.5和RCP8.5），分析了英国25个地点10个不利天气指数的频率、强度和空间格局的变化。预计英国未来气候仍将有利于小麦生产，到21世纪中叶，大多数不利天气指标的强度将会降低。更炎热干燥的夏季将改善播种和收获条件，并降低倒伏风险。2050年，生殖期和灌浆期出现晚霜和热胁迫的可能性可能仍然较小。冬季和春季更湿润可能会导致涝灾问题。2050年生殖期干旱胁迫的严重程度总体上会较低，然而局部差异表明在小空间尺度上研究干旱很重要。与欧洲其他地区可能出现的情况不同，英国长时间的水分胁迫不会大幅增加。基于CMIP5集合的气候预测显示，包括涝灾、干旱和水分胁迫在内的不利天气状况的强度存在相当大的不确定性。由于全球气候模型导致的不利天气状况变化通常大于不同排放情景之间的变化。因此，在评估作物生产的不利天气状况时，应使用CMIP5集合来表明可能影响的全部范围，而这是少数几个全球气候模型可能无法提供的。
