An Examination of Recent Increases in Great Lake-Effect Snowfall

提案0418012摘要Adam W.伯内特科尔盖特大学由于其热容量和地理环境，五大湖产生大量的湖泊效应降雪沿着其背风边缘在深秋和冬季时，冷大陆空气团穿越无冰湖面。 五大湖的物理特征和位置创造了一种独特的环境，在这种环境中，大规模气候的微妙变化，如与全球变暖有关的变化，可能转化为当地天气的重大变化。 几项研究表明，近几十年来，湖泊效应降雪量显著增加，而非湖泊效应地区的降雪量没有显著变化。 这些研究结果表明，在一个或多个气象或湖泊热力条件的变化，影响湖泊效应降水。 这些条件可能包括穿过湖泊的空气温度、湖水表面温度、湖泊冰盖、风向和风速。 该项目将评估这些因素与最近湖泊效应降雪增加的相关程度。 这项分析将涉及全面汇编五大湖地区所有现有的气温和降雪记录，并对数据进行空间检查，以确定不同湖泊影响地区的降雪量如何随时间变化。 对过去50年近地表风数据的分析将显示大气环流的变化在多大程度上导致湖泊效应降雪增加。 最后，所有可用的记录大湖水温和冰盖将被检查作为降雪变化的重要因素，这项研究谈到了如何在区域和地方尺度上表现出更广泛的气候变化的问题。五大湖地区降雪量持续增加的影响（积极和消极的）是显著的，涉及旅行危险、除雪成本、雪上娱乐影响、区域水文和市政供水、水力发电、土壤湿度和农业。 这项研究将有助于解决最近湖雪增加的原因，并确定这种增加是否与更广泛的气候变化模式相一致。

Abstract for Proposal 0418012Adam W. BurnettColgate UniversityBecause of their thermal capacity and geographic setting, the Great Lakes generate large quantities of lake-effect snowfall along their leeward margins during late autumn and winter when cold continental air masses travel across the ice-free lake surfaces. The physical characteristics and location of the Great Lakes create a unique setting in which subtle changes in broader-scale climate, such as that associated with global warming, might translate into significant changes in local weather. Several studies have shown that lake-effect snowfall has increased significantly in recent decades, whereas no significant snowfall changes have occurred in non-lake-effect areas. These findings suggest a change in one or more of the meteorological or lake thermal conditions that influence lake-effect precipitation. These conditions might include the temperature of the air moving across the lake, lake water surface temperature, lake ice cover, wind direction, and wind speed. This project will assess the degree to which these factors are associated with the recent increases in lake-effect snowfall. The analysis will involve a thorough compilation of all available air temperature and snowfall records for the Great Lakes region and a spatial examination of the data to determine how snowfall in different lake-effect regions has varied over time. An analysis of near-surface wind data over the past 50 years will show the degree to which changes in atmospheric circulation are contributing to lake-effect snow increases. Finally, all available records of Great Lake water temperature and ice cover will be examined as important factors in the snowfall changes.This study speaks to the question of how broader-scale variations in climate might manifest themselves at the regional and local scales. The implications (both positive and negative) for continued snowfall increases in the Great Lakes region are significant and involve travel hazards, snow removal costs, snow recreational impacts, regional hydrology and municipal water supplies, hydroelectric power production, and soil moisture and agriculture. This study will help to address the causes of recent lake snow increases and to determine whether such increases are consistent with broader patterns of climate change.