Changes in the Proportion of Precipitation Occurring as Rain in Northern Canada during Spring–Summer from 1979–2015
Changes in the form of precipitation have a considerable impact on the Arctic cryosphere and ecological system by influencing the energy balance and surface runoff. In this study, station observations and ERA-Interim data were used to analyze changes in the rainfall to precipitation ratio (RPR) in northern Canada during the spring–summer season (March–July) from 1979–2015. Our results indicate that ERA-Interim describes the spring–summer variations and trends in temperature and the RPR well. Both the spring–summer mean temperature [0.4°C–1°C (10 yr)-1] and the RPR [2%–6% (10 yr)-1] increased significantly in the Canadian Arctic Archipelago from 1979–2015. Moreover, we suggest that, aside from the contribution of climate warming, the North Atlantic Oscillation is probably another key factor influencing temporal and spatial differences in the RPR over northern Canada.
Key wordsclimate change rainfall to precipitation ratio northern Canada North Atlantic Oscillation
在北极地区, 不同形态的降水通过改变地表能量平衡和地表径流对冰冻圈和生态系统有非常重要的影响. 本文使用站点观测资料和ERA-Interim再分析资料对1979–2015年春夏季(3-7月)加拿大北部地区降雨量占总降水量比例(RPR)的变化特征进行分析. 结果表明, ERA-Interim再分析资料可以较好的表述春夏季地表气温和RPR的变化特征. 1979–2015年春夏季, 加拿大北极群岛的气温(0.4°C–1°C (10 yr)−1)和RPR(2%–6% (10 yr)−1)显著增加. 此外, 经研究发现, 除了气候变暖的影响之外, 北大西洋涛动可能是影响加拿大北部地区RPR时空分布特征的另一个关键因素.
关键词气候变化 降雨量占总降水量比例 加拿大北部 北大西洋涛动
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This study was supported by the National Key Basic Research Program of China (Grant No. 2013CBA01804), the National Science Foundation of China (Grant Nos. 41425003 and 41401079), the State Oceanic Administration of the People’s Republic of China Project on Climate in Polar Regions (Grant No. CHINARE2016-2020), the Key Research Program of the Chinese Academy of Sciences (Grant No. KJZD-EW-G03), and the Opening Founding of the State Key Laboratory of Cryospheric Sciences (Grant No. SKLCS-OP-2016-03). The authors would like to express their appreciation to Julian Morales for providing the daily meteorological data from Environment and Climate Change Canada.
- Aanes, R., B. E. Sæther, and N. A. Øritsland, 2000: Fluctuations of an introduced population of Svalbard reindeer: The effects of density dependence and climatic variation. Ecography, 23, 437–443, https://doi.org/10.1111/j.1600-0587.2000.tb00300.x CrossRefGoogle Scholar
- Barnston, A. G., and R. E. Livezey, 1987: Classification, seasonality, and persistence of low-frequency atmospheric circulation patterns. Mon. Wea. Rev., 115, 1083–1126, https://doi.org/10.1175/1520-0493(1987)115<1083:CSAPOL>2.0.CO;2 CrossRefGoogle Scholar
- Hasnain, S. I., 2002: Himalayan glaciers meltdown: Impact on south Asian rivers. Proc. Fourth International FRIEND Conf. Held at Cape Town, South Africa, IAHS, 274, 417–423.Google Scholar
- Wallace, J. M. and D. S. Gutzler, 1981: Teleconnections in the geopotential height field during the northern hemisphere win ter. Mon. Wea. Rev., 109, 784–812, https://doi.org/10.1175/1520-0493(1981)109<0784:TITGHF>2.0.CO;2 CrossRefGoogle Scholar
- Zhang, X. B., W. D. Hogg, and É. Mekis, 2001: Spatial and temporal characteristics of heavy precipitation events over Canada. J. Climate, 14, 1923–1936, https://doi.org/10.1175/1520-0442(2001)014<1923:SATCOH>2.0.CO;2 CrossRefGoogle Scholar