Projected twenty-first-century changes in the Central American mid-summer drought using statistically downscaled climate projections
Projected twenty-first-century changes in the Central American mid-summer drought using statistically downscaled climate projections
复制标题
使用统计上缩小的气候预测来预测二十一世纪中美洲仲夏干旱的变化
DOI：
10.1007/s10113-017-1177-6
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发表时间：
2017
影响因子：
4.2
通讯作者：
C. Bacon
中科院分区：
文献类型：
--
作者：
E. Maurer;N. Roby;I. T. Stewart;C. Bacon
除了周期性的长期干旱外，中美洲大部分地区还经历了雨季，两个高峰之间相隔数周至一个多月的干旱期，称为仲夏干旱。该地区的农民已经调整了他们的活动，以适应这一现象，预测其到来并估计其持续时间。全球变暖对该地区的众多影响包括预计降水量、变异性和时间的变化，有可能影响农业和粮食安全。使用网格化的日降水量为历史时期与未来的预测，我们的特点MSD在中美洲大部分地区使用四个措施：发病日期，持续时间，强度和最小值，并测试到21世纪末的显着变化。我们的研究结果表明，最显著的变化是持续时间，预计平均增加一周以上，MSD最小降水量预计平均减少26%以上，尼加拉瓜，洪都拉斯，萨尔瓦多萨尔瓦多，和危地马拉（假设21世纪排放量更高）。这些变化可能预示着对整个区域脆弱社区的粮食安全产生重要影响。我们发现，对于这四个指标，年际变化的变化是很小的历史变化相比，一般是统计上不显着的。
In addition to periodic long-term drought, much of Central America experiences a rainy season with two peaks separated by a dry period of weeks to over a month in duration, termed the mid-summer drought (MSD). Farmers in the region have adapted their activities to accommodate this phenomenon, anticipating its arrival and estimating its duration. Among the many impacts of global warming on the region are projected changes in precipitation amount, variability, and timing, with potential to affect agriculture and food security. Using gridded daily precipitation for a historic period with future projections, we characterize the MSD across much of Central America using four measures: onset date, duration, intensity, and minimum, and test for significant changes by the end of the twenty-first century. Our findings indicate that the most significant changes are for the duration, which is projected to increase by an average of over a week, and the MSD minimum precipitation, which is projected to decrease by an average of over 26%, with statistically significant changes for the mountains and Pacific side in most of Nicaragua, Honduras, El Salvador, and Guatemala (assuming a higher emissions pathway through the twenty-first century). These changes could portend important impacts on food security for vulnerable communities through the region. We find that for the four metrics, the changes in interannual variability are small compared to historical variability and are generally statistically insignificant.