Recent changes in southern Australian frost occurrence: implications for wheat production risk
Recent changes in southern Australian frost occurrence: implications for wheat production risk
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DOI：
10.1071/cp16056
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发表时间：
2016-01-01
影响因子：
1.9
通讯作者：
Nicholls, Neville
中科院分区：
文献类型：
--
作者：
Crimp, Steven Jeffery;Zheng, Bangyou;Nicholls, Neville
在澳大利亚，霜冻危害仍然是大田种植、葡萄栽培、园艺和其他农业产业的主要问题。据估计，澳大利亚阔叶地农业每年因霜冻事件造成的损失在1.2亿至7亿美元之间。了解霜冻风险的变化性质以及责任驱动因素，是帮助许多生产者管理气候变异性和变化的重要步骤。我们的分析，使用史蒂文森屏幕温度阈值为2摄氏度或更低作为地面霜冻的指标，表明在澳大利亚南部，尽管自1960年以来每十年变暖0.17摄氏度的趋势，霜冻季节的长度平均增加了26天，与1960-1990年的长期平均值相比，整个澳大利亚南部。澳大利亚东南部的一些地区现在经历的最后一次霜冻比20世纪60年代平均晚了4周。在澳大利亚小麦带的60个地点对霜冻和小麦生产风险的交叉点进行了量化，并对维多利亚的15个地点进行了更深入的分析（即国家和维多利亚评估共有的8个地点和维多利亚分析专用的7个地点）。国家评估的结果强调了在过去二十年中，澳大利亚小麦带大部分地区与霜冻相关的生产风险增加了30%，对于一系列小麦成熟度类型，以应对后期霜冻事件的增加。在维多利亚州的15个地点，在只有10%的机会发生0摄氏度的夜晚期间达到开花期的播种日期，短季品种转移了23天（6月6日），中季品种转移了20天（5月17日），长季品种转移了36天（5月9日）。
Frost damage remains a major problem for broadacre cropping, viticulture, horticulture and other agricultural industries in Australia. Annual losses from frost events in Australian broadacre agriculture are estimated at between $120million and $700million each year for this sector. Understanding the changing nature of frost risk, and the drivers responsible, are important steps in helping many producers manage climate variability and change. Our analysis, using Stevenson screen temperature thresholds of 2 degrees C or below as an indicator of frost at ground level, demonstrates that across southern Australia, despite a warming trend of 0.17 degrees C per decade since 1960, frost season' length has increased, on average, by 26 days across the whole southern portion of Australia compared with the 1960-1990 long-term mean. Some areas of south-eastern Australia now experience their last frost an average 4 weeks later than during the 1960s. The intersection of frost and wheat production risk was quantified at 60 sites across the Australian wheatbelt, with a more in-depth analysis undertaken for 15 locations across Victoria (i.e. eight sites common to both the National and Victorian assessments and seven sites exclusive to the Victorian analysis). The results of the national assessment highlight how frost-related production risk has increased by as much as 30% across much of the Australian wheatbelt, for a range of wheat maturity types, over the last two decades, in response to an increase in later frost events. Across 15 Victorian sites, sowing dates to achieve anthesis during a period with only a 10% chance of a 0 degrees C night occurring shifted by 23 days (6 June) for the short-season variety, 20 days (17 May) for the medium-season variety and 36 days later (9 May) for the long-season variety assessed.