气候变化领域集成服务门户(CCPortal): Near-0°C surface temperature and precipitation type patterns across Canada

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DOI	10.5194/hess-24-1741-2020
	Near-0°C surface temperature and precipitation type patterns across Canada
	Mekis E.; Stewart R.E.; Theriault J.M.; Kochtubajda B.; Bonsal B.R.; Liu Z.
发表日期	2020
ISSN	1027-5606
起始页码	1741
结束页码	1761
卷号	24 期号:4
英文摘要	The 0 °C temperature threshold is critical for many meteorological and hydrological processes driven by melting and freezing in the atmosphere, surface, and sub-surface and by the associated precipitation varying between rain, freezing rain, wet snow, and snow. This threshold is especially important in cold regions such as Canada, because it is linked with freeze thaw, snowmelt, and permafrost. This study develops a Canada-wide perspective on near-0 °C conditions using hourly surface temperature and precipitation type observations from 92 climate stations for the period from 1981 to 2011. In addition, nine stations from various climatic regions are selected for further analysis. Near-0 °C conditions are defined as periods when the surface temperature is between ..2 and 2 °C. Near-0 °C conditions occur often across all regions of the country, although the annual number of days and hours and the duration of these events varies dramatically. Various types of precipitation (e.g., rain, freezing rain, wet snow, and ice pellets) sometimes occur with these temperatures. Near-0 °C conditions and the reported precipitation type occurrences tend to be higher in Atlantic Canada, although high values also occur in other regions. Trends of most temperature-based and precipitation-based indicators show little or no change despite a systematic warming in annual surface temperatures over Canada. Over the annual cycle, near-0 °C temperatures and precipitation often exhibit a pattern: short durations occur around summer, driven by the diurnal cycle, and a tendency toward longer durations around winter, associated with storms. There is also a tendency for near-0 °C surface temperatures to occur more often than expected relative to other temperature windows at some stations due, at least in part, to diabatic cooling and heating that take place with melting and freezing, respectively, in the atmosphere and at the surface. © 2020 BMJ Publishing Group. All rights reserved.
语种	英语
scopus关键词	Freezing; Melting; Rain; Snow; Surface properties; Climate stations; Climatic regions; Freezing rain; Hydrological process; Short durations; Surface temperatures; Temperature thresholds; Temperature window; Atmospheric temperature; heating; hydrometeorology; precipitation (climatology); seasonal variation; storm; surface temperature; Canada
来源期刊	Hydrology and Earth System Sciences
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/159444
作者单位	Mekis, E., Meteorological Research Division, Environment and Climate Change Canada, Toronto, M3H 5T4, Canada; Stewart, R.E., Department of Environment and Geography, University of Manitoba, Winnipeg, R3T 2N2, Canada; Theriault, J.M., Centre Escer, Department of Earth and Atmospheric Sciences, Université du Québec À Montréal, Montréal, H2X 3Y7, Canada; Kochtubajda, B., Meteorological Service of Canada, Environment and Climate Change Canada, Edmonton, T6B 1K5, Canada; Bonsal, B.R., Watershed Hydrology and Ecology Research Division, Environment and Climate Change Canada, Saskatoon, S7N 3H5, Canada; Liu, Z., Department of Environment and Geography, University of Manitoba, Winnipeg, R3T 2N2, Canada
推荐引用方式 GB/T 7714	Mekis E.,Stewart R.E.,Theriault J.M.,et al. Near-0°C surface temperature and precipitation type patterns across Canada[J],2020,24(4).
APA	Mekis E.,Stewart R.E.,Theriault J.M.,Kochtubajda B.,Bonsal B.R.,&Liu Z..(2020).Near-0°C surface temperature and precipitation type patterns across Canada.Hydrology and Earth System Sciences,24(4).
MLA	Mekis E.,et al."Near-0°C surface temperature and precipitation type patterns across Canada".Hydrology and Earth System Sciences 24.4(2020).